bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Predicting the Price of Coconut in Tamil Nadu Market
Authors: Ahalya S. P. , Murugananthi D. , Rohini A. , Devi R. Parimala , Kalpana M.
Published: September 2023

Aims: The study aims to comprehensively analyze coconut cultivation trends in Tamil Nadu, covering area, production, yield, and market prices. Through data analysis, it seeks to reveal historical shifts in cultivation practices. The study also strives to develop precise price forecasting models for Coimbatore and Pollachi markets, enhancing insights into agricultural dynamics and enabling accurate price predictions.

Study Design:  Exploratory research design.

Place and Duration of Study: The present study was conducted in the year 2023 during July and August

Methodology: Secondary data was used for the present study.  Secondary Data on area , production and productivity of coconut in Tamil Nadu was collected from 2000 to 2022 and price of coconut from 2012 to 2023 in selected market was collected. The research utilizes Compound Annual Growth Rate (CAGR) Analysis to identify the past trends in the area, production, and productivity of coconut in Tamil Nadu. Additionally, the Autoregressive Integrated Moving Average (ARIMA) models are employed to forecast the future trens in coconut price in Coimbatore and Pollachi market.

Results: Area, Production and Productivity of coconut in Tamilnadu has shown a positive trend. Coconut cultivation is growing steadily with a 1.56% increase in cultivation area and a 2.089% rise in production, while productivity is also improving by 1.19% annually, indicating positive growth. ARIMA (1, 1, 1) for Coconut in the Coimbatore market and ARIMA (1, 1, 1) for coconut in the Pollachi market was found to provide the best fit for predicting the price of coconut in both markets.

Conclusion: Increase in trend in area, production and productivity was observed in Tamil Nadu. ARIMA (1, 1, 1) was found to provide the best fit for predicting the price of coconut in both markets. The model predicted declining price in the forthcoming months (August – September, 2023). Increased area under cultivation and increased production of coconut in all the major growing States are the major reasons for declining prices. Efforts have to be made to increase the consumption of coconut value added products to sustain the price of coconut in the coming years.
Roles of Instructors in Enhancing Open and Distance Learning (ODL) Towards Learners’ Academic Progress in Iringa Municipality, Tanzania
Authors: Mwila Camillus A.
Published: September 2023

Most of the Open and Distance Learning students face the challenges of poor academic progress when they relay on private and self-learning without any assistance from the teachers (instructors). Therefore, this study assessed the role of Instructors in Enhancing Open and Distance Learning (ODL) Towards Learners’ Academic Progress in Iringa Municipality, Tanzania. Specifically, the study had two research questions namely: What are the services performed by instructors in enhancing learning through ODL in Iringa Municipality? What are the impacts of instructors in facilitating ODL learners toward academic performance? The study was methodologically operationalized by qualitative research approach and was guided by case study design. The target population was the Regional Resident Tutor, instructors and students from Open and Distance Learning (ODL). The total sample size involved 40 respondents. Data was collected through interview and focus group discussion methods. The data were analysed through the use of thematic analysis. The findings of this study revealed that provision of study materials such as modules and notes for further reading, face-to-face meetings, and guidance and counselling services are the services provided by ODL. Furthermore, this study revealed out that instructors have a great role in Open and Distance Learning leaners since, the guidance and counselling services provided to the students help them in various ways such as improving their studying skills and techniques. It is concluded that Tanzania government under the High Education Students Loan Board (HESLB) should provide loans even for ODL students to reduce the cost of education such as tuition fee, stationery, accommodation and meal. Finally, the government should oversee again the cost of ODL if possible, there is also a need to reduce the tuition fee and improve the infrastructure and resources such as libraries, classes and ICT facilities and services.
The Strategy of Phytoplankton Administration in Larval Rearing to Improve the Survival Rate of White Shrimp (Penaeus vannamei) Larvae of F1 and Free-Pathogen
Authors: Illijas Muhammad Ikbal , Saleh Luqman , Arma Nur Rahmawaty , Andriani  , Mulyani Rahmi
Published: September 2023

Aims: The white shrimp (Penaeus vannamei) larvae F1 is the dream of shrimp cultivators to be cultivated in ponds. This is because F1 larvae have fast growth, especially if the larvae have disease-free certification (specific pathogen-free, SPF). The purpose of this scientific paper is to evaluate strategies for feeding phytoplankton in larval rearing to increase the survival rate of shrimp larvae F1 of white shrimp.

Place and Duration of Study: This research activity was carried out from November to December 2021 at the Shrimp Hatchery Laboratory, Department of Aquaculture Technology, Pankep State Polytechnic Agriculture.

Methodology: The nauplii were obtained from the shrimp hatchery industry and then stocked in 2 units of tanks measuring 4m x 4m x 1.5m. Before stocking, the larvae were acclimatized to temperature (28°C) and salinity (30 ppt). The larvae were fed live feed (Skeletonema costatum) from the stage of Nauplii-6 to Mysis-2. In addition, the larvae were also fed artificial feeds and Artemia nauplii. Observation of larval development was carried out at each stage using a microscope (40x), and observations of the population number of each stage were carried out volumetrically. Parasite analysis of each stage was conducted in the Makassar Fish Quarantine.

Results: The results showed that during the stage shift from Nauplius-6 to Zoea-1, the larvae succeeded in passing the zoea syndrome (empty intestine). The population decline was only reduced by 2% (from 1,200,000 individuals decreased to 1,175,600 individuals). The final population (PL10) was 1,084,000 (SR 90%). The parasite analyses results showed that the larvae were free from any disease. Administration of phytoplankton (S. costatum ) at the early stage (Nauplius-6) at a dose of 60 x 106 cells/ml has succeeded in reducing the mortality rate (2%) in the critical stage (zoea syndrome) of F1 white shrimp larvae.
Varietal Evaluation in Marigold (Tagetes spp.) Under Prayagraj Agro Climatic Conditions
Authors: Kumar Shubham , Prasad V. M. , Topno Samir E.
Published: September 2023

A field experiment was carried out in the Department of Horticulture, Naini Agricultural Institute, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj. During rabi season (2021-2023). The aim of this study was to determine to find out the most suitable variety of marigold in terms of growth, yield and quality under Prayagraj Agro climatic conditions and to work out the economics of different varieties of marigold. The experiment was laid out in Randomized block design (RBD) with 10 varieties and each replicated thrice. The variety Inca (m) Orange reported significantly better Performance compared to other varieties, in terms of Growth parameters like plant height (67.67 cm), Number of branches per plant (11.17), Leaf length (9.47), Plant spread (35.70) and Yield parameters like Flower yield per plant (272.08 g), Flower yield per plot (1632.50), Flower yield per ha (14.41 t).
Effect of Organic Manure and Bio Fertilizer on Growth, Yield and Quality in Cabbage
Authors: Singh Harshvardhan , Kerketta Anita , Prasad V. M. , Bahadur Vijay
Published: September 2023

The Department of Horticulture at the Naini Agricultural Institute Sam Higginbottom University of Agriculture, Technology & Sciences, Prayagraj (UP) conducted an experiment in 2022 to investigate the "Effect of organic manures and biofertilizers on growth, yield, and quality in cabbage (Brassica oleraceae L. Var. capitata)". There were ten treatments totaling various amounts of organic manure and bio-fertilizer, with water serving as the control. At 20, 40, and 60 days after transplantation, the treatment is sprayed. The plot size was kept at 2 m × 1.5 m, and each treatment was reproduced three times in a randomized block design. The best results were achieved with treatment T6 (Farm Yard Manure @20t/ha + Bio-Fertilizer (Azotobacter + PSB) each @5kg/ha). The maximum plant height (24.33 cm), the plant's spread (68.59), the number of leaves per plant (13.67), the average head weight (1.93 kg), the head's compactness (5.56 Kg/inch), the yield per plot (6.93 kg), the yield per hectare (71.60 t/ha), the TSS (5.9 Brix), and the amount of ascorbic acid per 100g.Under T6, the gross return (Rs 221430/ha), net profit (Rs 172530/ha), and B:C ratio (4.52) were all much greater. Overall results revealed that the application of FYM @20t/ha + Biofertilizer @5kg/ha proved to be better for different growth, yield and quality traits in cabbage.
Effect of Integrated Application of Bio-Fertilizer and Soil Amendments on Growth Parameters of Groundnut (Arachis hypogaea L.)
Authors: Ghosh Animesh , Gautam Sandip Kumar , Meetei Thounaojam Thomas , Singh Nivedita , Shrivastava Akansha , Patel Satyam
Published: September 2023

The pot experiment entitled “Effect of integrated application of bio-fertilizer and soil amendments on Growth parameters of Groundnut (Arachis hypogaea L.)’’ was conducted at the Research Farm of School of Agriculture, ITM University, during kharif season 2022. The soil of the experimental field was sandy loam, having a pH of 8.13, EC of 0.54 ds m-1, organic carbon 0.40%, available N, P, K of 180, 11.09 and 283.40 kg ha-1 respectively and exchangeable Ca+Mg of 1.5 me 100 g-1soil. The pot experiment was laid out in CRD (Completely Randomized Design) with six treatments and six replications. The treatment combinations were: T1- Control, T2- Recommended Dose of Fertilizer (N, P2O5 and K2O @ 20, 40 and 20 kg ha-1 respectively), T3- FYM (10 t ha-1), T4- Rhizobium (Bradyrhizobium japonicum) @ 200 gm 10 kg-1 seeds, T5- RDF + Rhizobium, T6- Rhizobium + FYM. The nodulation (number of nodules and nodules dry weight) was increased with combine application of rhizobium inoculation and FYM over the time (30 and 60 DAS) followed by RDF and rhizobium inoculation. The growth attributes viz. plant biomass, shoot length, root length was significantly improved with the integration of bio-fertilizer, FYM and inorganic fertilizers. The highest result for plant biomass (22.34 gm plant-1) and shoot length (21.78 cm) were recorded in rhizobium inoculation and FYM treatment combination but root length (8.87 cm) was recorded highest in combine application of RDF with rhizobium. Application of rhizobium with FYM (25.74 gm pot-1) produce the highest pod yield followed by RDF and rhizobium (23.65 gm pot-1) combination. The combination of RHZ + FYM has much more favorable results on growth and yield of groundnut and it also enhance the nodulation.
Studies on Heterosis for Pod Yield and Protein Content in Yardlong Bean (Vigna unguiculata (L.) Walp. ssp. Sesquipedalis Verdc.)
Authors: Ratnakumari N. , Naidu L. Naram , Reddy R. V. S. K. , Patro T. S. K. K. Kiran , Babu D. Ratna , Umakrishna K.
Published: September 2023

A set of 29 genotypes including 7 parents, their 21 resultant hybrids and one commercial check variety (Arka Mangala) were sown during summer, 2019 at the College Instructional Farm, College of Horticulture, Venkataramannagudem to study the magnitude of heterosis using half diallel analysis for eleven characters. Significant differences were observed among the parents and hybrids indicating considerable genetic variation among these genotypes. Significant standard heterosis and high per se performance with regards to fruit yield per plant were recorded by the crosses viz., Babli x Lola , Babli x Bobbili Local, Babli x Trivendrum Local, Bobbili Local x Lola, Bobbili Local x Trivendrum Local and Lola x Trivendrum Local.
Calcium Nutrition for Improving the Growth and Yield of Carrot in Acid Soils
Authors: Aparna B. , Chitdeshwari T. , Suganya S. , Kavitha C. , Geetha P.
Published: September 2023

Aims: To evaluate the effect of various sources, levels and methods of calcium application on the growth, yield and SPAD index of carrots grown on acid soils

Study Design: Factorial randomized block design (FRBD) with three replications.

Place and Duration of Study: A field experiment was conducted in the farmer’s field at Takkarbaba Nagar, Ooty from February to June, 2023.

Methodology: A field experiment was conducted with carrot hybrid Zubera using lime at 50% LR and dolomite at 20,40,60 and 80 kg Ca ha-1 as basal soil application and foliar spraying of 0.5% calcium EDTA and calcium citrate twice on 30 and 45 DAP in a factorial randomized block design with three replications. The growth parameters such as plant height, petiole length, number of leaves per plant, SPAD index and tuber yield were recorded as per standard protocols at different plant growth stages viz., vegetative, tuber development and harvest stages.

Results: A significant linear increase in plant height, petiole length, number of leaves per plant, SPAD index and tuber yield was recorded with the supplementation of calcium at different levels. Higher plant height (26.3 cm, 51.2 cm and 56.1 cm), petiole length (13.8 cm, 23.0 cm and 35.8 cm), number of leaves per plant (7.62, 7.82 and 9.30), SPAD index (22.0, 38.0 and 35.2) and fresh tuber yield (37.2 t ha-1) was registered with NPK+ 80 kg Ca as dolomite along with two sprays of 0.5% Ca EDTA twice which was followed by the same level of calcium as dolomite + foliar spraying of 0.5% calcium citrate twice. The minimum growth and yield response of carrot at all the growth stages was noticed with NPK control.

Conclusion: Application of calcium through soil and foliar spraying showed synergistic influence on the growth and SPAD index of carrot at all stages of growth. Application of NPK+ 80 kg Ca ha-1 as dolomite performed better when compared to lime applied at 50% LR. Between Ca EDTA and Ca citrate, the performance of Ca EDTA was better in improving the growth and yield of carrot. It was concluded that the combined application of soil test based NPK+80 kg Ca ha-1 as dolomite along with two sprays of 0.5% calcium EDTA on 30 and 45 DAP would be effective in improving the growth, yield and SPAD index of carrot grown on acid lateritic soils.
Influence of Different Residue Retention and Nutrient Levels on Crop Productivity of Soybean (Glycine max L.) under Conservation Agriculture
Authors: Parmar Bharti , Vishwakarma A. K. , Gupta Varsha , Jha Pramod , Biswas A. K. , Hati K. M. , Malgaya Ganesh , Nagwanshi Anil , Singh Shubham , Yadav Rupesh
Published: September 2023

During the kharif season of 2020-22, a field experiment with soybean in a soybean-wheat cropping system was conducted at the ICAR-Indian Institute of Soil Science, Bhopal, (M.P.) to assess the effect of different levels of crop residue retention treatments and nutrient doses on growth parameters, physiological indices, yield attributes, yield and profitability of soybean. The experiment was laid out with Factorial Randomized Block Design (FRBD) comprised of 16 combinations of 4 residue level (0%, 30%, 60% and 90%) and 4 nutrient doses (N1-RDF (120:60:40 kg N, P2O5 and K2O ha-1), N2-75% N+100% P2O5 and K2O ha-1, N3-75% P2O5+100% N and K2O ha-1, N4-75% K2O+100% N and P2O5 ha-1) with 3 replication under ongoing CRP-CA (Consortium Research Platform on Conservation Agriculture). The result showed that growth parameters, physiological indices as well as yield, yield attributes and profitability were significantly higher in 90% than other crop reside retention treatment. The higher (90%) crop residue retention resulted in 16% higher grain yield, 16.88% stover yield and 17.55% higher profitability then without residue treatment. Among different nutrient doses 100% RDF showed significantly higher growth and better physiological indices at all the growth stages. Significantly higher seed (1226 kg ha-1) and stover (2274 kg ha-1) yields were recorded with 100% RDF with any other management practices.
Pediatric Hospitalizations at Rural and Urban Teaching and Nonteaching Hospitals in the US, 2009-2019
Authors: Leyenaar JoAnna K. , Freyleue Seneca D. , Arakelyan Mary , Goodman David C. , O’Malley A. James
Published: September 2023

Importance

National analyses suggest that approximately 1 in 5 US hospitals closed their pediatric units between 2008 and 2018. The extent to which pediatric hospitalizations at general hospitals in rural and urban communities decreased during this period is not well understood.

Objective

To describe changes in the number and proportion of pediatric hospitalizations and costs at urban teaching, urban nonteaching, and rural hospitals vs freestanding children’s hospitals from 2009 to 2019; to estimate the number and proportion of hospitals providing inpatient pediatric care; and to characterize changes in clinical complexity.

Design, Setting, and Participants

This study is a retrospective cross-sectional analysis of the 2009, 2012, 2016, and 2019 Kids’ Inpatient Database, a nationally representative data set of US pediatric hospitalizations among children younger than 18 years. Data were analyzed from February to June 2023.

Exposures

Pediatric hospitalizations were grouped as birth or nonbirth hospitalizations. Hospitals were categorized as freestanding children’s hospitals or as rural, urban nonteaching, or urban teaching general hospitals.

Main Outcomes and Measures

The primary outcomes were annual number and proportion of birth and nonbirth hospitalizations and health care costs, changes in the proportion of hospitalizations with complex diagnoses, and estimated number and proportion of hospitals providing pediatric care and associated hospital volumes. Regression analyses were used to compare health care utilization in 2019 vs that in 2009.

Results

The data included 23.2 million (95% CI, 22.7-23.6 million) weighted hospitalizations. From 2009 to 2019, estimated national annual pediatric hospitalizations decreased from 6 425 858 to 5 297 882, as birth hospitalizations decreased by 10.6% (95% CI, 6.1%-15.1%) and nonbirth hospitalizations decreased by 28.9% (95% CI, 21.3%-36.5%). Concurrently, hospitalizations with complex chronic disease diagnoses increased by 45.5% (95% CI, 34.6%-56.4%), and hospitalizations with mental health diagnoses increased by 78.0% (95% CI, 61.6%-94.4%). During this period, the most substantial decreases were in nonbirth hospitalizations at rural hospitals (4-fold decrease from 229 263 to 62 729) and urban nonteaching hospitals (6-fold decrease from 581 320 to 92 118). In 2019, birth hospitalizations occurred at 2666 hospitals. Nonbirth pediatric hospitalizations occurred at 3507 hospitals, including 1256 rural hospitals and 843 urban nonteaching hospitals where the median nonbirth hospitalization volumes were fewer than 25 per year.

Conclusions and Relevance

Between 2009 and 2019, the largest decreases in pediatric hospitalizations occurred at rural and urban nonteaching hospitals. Clinical and policy initiatives to support hospitals with low pediatric volumes may be needed to maintain hospital access and pediatric readiness, particularly in rural communities.
The CNN model aided the study of the clinical value hidden in the implant images
Authors: Huang Xinxu , Chen Xingyu , Zhong Xinnan , Tian Taoran
Published: September 2023

Purpose

This article aims to construct a new method to evaluate radiographic image identification results based on artificial intelligence, which can complement the limited vision of researchers when studying the effect of various factors on clinical implantation outcomes.

Methods

We constructed a convolutional neural network (CNN) model using the clinical implant radiographic images. Moreover, we used gradient‐weighted class activation mapping (Grad‐CAM) to obtain thermal maps to present identification differences before performing statistical analyses. Subsequently, to verify whether these differences presented by the Grad‐CAM algorithm would be of value to clinical practices, we measured the bone thickness around the identified sites. Finally, we analyzed the influence of the implant type on the implantation according to the measurement results.

Results

The thermal maps showed that the sites with significant differences between Straumann BL and Bicon implants as identified by the CNN model were mainly the thread and neck area. (2) The heights of the mesial, distal, buccal, and lingual bone of the Bicon implant post‐op were greater than those of Straumann BL (P < 0.05). (3) Between the first and second stages of surgery, the amount of bone thickness variation at the buccal and lingual sides of the Bicon implant platform was greater than that of the Straumann BL implant (P < 0.05).

Conclusion

According to the results of this study, we found that the identified‐neck‐area of the Bicon implant was placed deeper than the Straumann BL implant, and there was more bone resorption on the buccal and lingual sides at the Bicon implant platform between the first and second stages of surgery. In summary, this study proves that using the CNN classification model can identify differences that complement our limited vision.
Breaking the Tradeoffs between Different Mechanical Properties in Bioinspired Hierarchical Lattice Metamaterials
Authors: Wang Peng , Yang Fan , Zheng Bailin , Li Pengfei , Wang Ruicheng , Li Yan , Fan Hualin , Li Xiaoyan
Published: September 2023

It is a long‐standing challenge to break the tradeoffs between different mechanical property indicators such as the strength versus toughness in the design of lightweight lattice materials. To tackle this challenge, a hierarchical lattice metamaterial with modified face‐centered cubic (FCC) cell configuration, inspired by the glass sponge skeletal system, is proposed. The proposed lattice metamaterial simultaneously possesses high strength, high energy absorption, considerable toughness, as well as controllable deformation patterns through integration of both bionic features of double diagonal reinforcement and hierarchical circular modification. The compressive strength and energy absorption can reach 69.13 MPa and 53.39 J cm3, respectively. Furthermore, the proposed lattice also exhibits exceptionally high damage tolerance compared with existing lattice metamaterials with comparable strength by attenuating stress and deformation concentration that may cause catastrophic collapse. This design approach combines the advantages of tensile‐dominated and bending‐dominated lattices. Quantitatively, in terms of specific strength, specific energy absorption, and crushing force efficiency, the modified hierarchical circular FCC (MHCFCC) lattice metamaterial outperforms the Octet lattice by 14.85%, 53.28%, and 110.52%, respectively. This multibionic feature integration approach provides advanced design strategies for high‐performance architected metamaterials with promising application potential.
Indoor Self‐Powered Perovskite Optoelectronics with Ultraflexible Monochromatic Light Source
Authors: Jinno Hiroaki , Shivarudraiah Sunil B. , Asbjörn Rasmussen , Vagli Gianluca , Marcato Tommaso , Eickemeyer Felix Thomas , Pfeifer Lukas , Yokota Tomoyuki , Someya Takao , Shih Chih‐Jen
Published: September 2023

Self‐powered skin optoelectronics fabricated on ultrathin polymer films is emerging as one of the most promising components for the next‐generation Internet of Things (IoT) technology. However, a longstanding challenge is the device underperformance owing to the low process temperature of polymer substrates. In addition, broadband electroluminescence (EL) based on organic or polymer semiconductors inevitably suffers from periodic spectral distortion due to Fabry–Pérot (FP) interference upon substrate bending, preventing advanced applications. Here, ultraflexible skin optoelectronics integrating high‐performance solar cells and monochromatic light‐emitting diodes using solution‐processed perovskite semiconductors is presented. n–i–p perovskite solar cells and perovskite nanocrystal light‐emitting diodes (PNC‐LEDs), with power‐conversion and current efficiencies of 18.2% and 15.2 cd A−1, respectively, are demonstrated on ultrathin polymer substrates with high thermal stability, which is a record‐high efficiency for ultraflexible perovskite solar cell. The narrowband EL with a full width at half‐maximum of 23 nm successfully eliminates FP interference, yielding bending‐insensitive spectra even under 50% of mechanical compression. Photo‐plethysmography using the skin optoelectronic device demonstrates a signal selectivity of 98.2% at 87 bpm pulse. The results presented here pave the way to inexpensive and high‐performance ultrathin optoelectronics for self‐powered applications such as wearable displays and indoor IoT sensors.
Phosphorescent Carbene‐Gold‐Arylacetylide Materials as Emitters for Near UV‐OLEDs
Authors: Brannan Alexander C. , Cho Hwan‐Hee , Reponen Antti‐Pekka M. , Linnolahti Mikko , Bochmann Manfred , Greenham Neil C. , Romanov Alexander S.
Published: September 2023

A series of carbene‐gold‐acetylide complexes [(BiCAAC)AuCC]nC6H5−n (n = 1, Au1; n = 2, Au2; n = 3, Au3; BiCAAC = bicyclic(alkyl)(amino)carbene) have been synthesized in high yields. Compounds Au1–Au3 exhibit deep‐blue to blue‐green phosphorescence with good quantum yields up to 43% in all media. An increase of the (BiCAAC)Au moieties in gold complexes Au1–Au3 increases the extinction coefficients in the UV–vis spectra and stronger oscillator strength coefficients supported by theoretical calculations. The luminescence radiative rates decrease with an increase of the (BiCAAC)Au moieties. The time‐dependent density functional theory study supports a charge‐transfer nature of the phosphorescence due to the large (0.5–0.6 eV) energy gap between singlet excited (S1) and triplet excited (T1) states. Transient luminescence study reveals the presence of both nonstructured UV prompt‐fluorescence and vibronically resolved long‐lived phosphorescence 428 nm. Organic light‐emitting diodes (OLED) are fabricated by physical vapor deposition with 2,8‐bis(diphenylphosphoryl)dibenzo[b,d]furan (PPF) as a host material with complex Au1. The near‐UV electroluminescence is observed at 405 nm with device efficiency of 1% while demonstrating OLED device lifetime LT50 up to 20 min at practical brightness of 10 nits, indicating a highly promising class of materials to develop stable UV‐OLEDs.
Polymer Boosts High Performance Perovskite Solar Cells: A Review
Authors: Ma Yabin , Ge Jinghao , Jen Alex K.‐Y. , You Jiaxue , Liu Shengzhong (Frank)
Published: September 2023

Perovskite solar cells (PSCs) with excellent photoelectric properties have attracted much attention in recent years. However, the solution manufacturing of PSCs inevitably introduces a large number of defects (both bulk and surface defects), which seriously affect the performance of PSCs. Defect passivation from additive engineering is an effective and simple strategy. Among these additives, polymers are increasingly attracting attention due to their excellent properties, such as adjustable structures, multiple functional groups, excellent stability, and low cost, which can further promote the commercialization of PSC technology. However, the application of polymers in PSCs have encountered some obstacles due to a lack of systematic studies, such as unelucidated interactions between polymers and perovskites, the frequent trial‐and‐error process used in material selection, and the lack of effective guidelines. In this review, the application of polymers in various layers of PSCs devices is first summarized. Then, three main roles of polymers in PSCs are summarized, including crystallization regulation, the mechanical stability enhancement of flexible perovskite solar cells (FPSCs), and their use as undoped hole transport materials (HTMs). More importantly, machine learning (ML) is proposed to design and select polymers as passivators and HTMs for PSCs. Finally, promising guidelines and recommendations are provided for the commercialization of PSCs.
Coordination Trap Induced Structural and Luminescent Property Transformation of Low Dimensional Organic‐Inorganic Hybrid Perovskites
Authors: Yang Xinxin , Wang Shuaiqi , Wu Junyan , Hu Wei , Huang Limei , Ling Qidan , Lin Zhenghuan
Published: September 2023

Herein, a coordination trap strategy is proposed for constructing stimulus‐responsive phosphorescent perovskites. Hydroxyl groups are selected as trap groups and introduced into benzylamine hydrochloride of Cd‐based perovskite. The resulting two‐dimensional (2D) perovskite (C7H10NO)2CdCl4·H2O (H1) exhibits blue fluorescence at 405 nm and green phosphorescence at 482 nm under 365 nm excitation. After introducing guest Mn2+, due to the passivation of defects, the doped H1 (H1‐M) achieves orange phosphorescence (λ = 615 nm) of Cd2+. Interestingly, because thermal stimulation induces the coordination of hydroxyl groups with metal ions, H1 and H1‐M are transformed into the zero‐dimensional (0D) perovskite (C7H10NO)2CdCl4 (H2) and doped H2 (H2‐M), respectively. The coordination immobilizes the organic molecules, thus resulting in a large increase in the phosphorescence lifetime and a strong green afterglow of H2. The coordination also transforms the luminescent center of the doped perovskite from the host metal ion of H1‐M to the guest metal ion of H2‐M, achieving red phosphorescence of Mn2+ at 685 nm. Under water vapor, H2 and H2‐M are reversibly converted to H1 and H1‐M, respectively. Based on the above phenomena, a multilevel anti‐counterfeit encryption system with water/heat stimulus‐response is developed, which provides a new idea for the design of stimulus‐responsive phosphorescent intelligent materials.
The Influence of the Reaction Conditions on the Photocatalytic Gas‐Phase Conversion of Methanol with Water Vapor over Pt/SrTiO3 in a Continuously Operated Flow Reactor
Authors: Deitermann Michel , Haver Yannik , Mei Bastian Timo , Muhler Martin
Published: September 2023

Continuous methanol photooxidation in the gas phase is a promising method to produce valuable chemicals like formaldehyde or methyl formate in addition to hydrogen under mild conditions. The influence of the reaction conditions on the selectivity of methanol oxidation to formaldehyde is studied using a heated flat‐plate flow photoreactor illuminated by an LED array (λmax = 368 nm) and Pt‐modified SrTiO3. A combination of online analytical methods allowed to quantify all gaseous products during extended time‐on‐stream (> 48 h TOS). The selectivity to formaldehyde is found to be primarily determined by the residence time and the process temperature. At a low methanol to water ratio, methanol conversion and evolution of CO2 are favored, whereas the light intensity primarily influenced the apparent quantum yield from 5.1 to 1.8% at 9.36 to 52.93 mW cm−2, respectively, and the methanol conversion thus determining the economic efficiency of the process. Operation temperatures higher than 110 °C resulted in a strong deactivation of the catalyst while simultaneously the formation of CO at the expense of formaldehyde selectivity is favored. This study demonstrates the importance of understanding the influence of relevant reaction conditions and the potential of selective photocatalytic gas‐phase oxidation of small molecules.
Retinal Microenvironment‐Protected Rhein‐GFFYE Nanofibers Attenuate Retinal Ischemia‐Reperfusion Injury via Inhibiting Oxidative Stress and Regulating Microglial/Macrophage M1/M2 Polarization
Authors: Zhang Zhuhong , Peng Shengjun , Xu Tengyan , Liu Jia , Zhao Laien , Xu Hui , Zhang Wen , Zhu Yuanying , Yang Zhimou
Published: September 2023

Retinal ischemia is involved in the occurrence and development of various eye diseases, including glaucoma, diabetic retinopathy, and central retinal artery occlusion. To the best of our knowledge, few studies have reported self‐assembling peptide natural products for the suppression of ocular inflammation and oxidative stress. Herein, a self‐assembling peptide GFFYE is designed and synthesized, which can transform the non‐hydrophilicity of rhein into an amphiphilic sustained‐release therapeutic agent, and rhein‐based therapeutic nanofibers (abbreviated as Rh‐GFFYE) are constructed for the treatment of retinal ischemia‐reperfusion (RIR) injury. Rh‐GFFYE significantly ameliorates oxidative stress and inflammation in an in vitro oxygen‐glucose deprivation (OGD) model of retinal ischemia and a rat model of RIR injury. Rh‐GFFYE also significantly enhances retinal electrophysiological recovery and exhibits good biocompatibility. Importantly, Rh‐GFFYE also promotes the transition of M1‐type macrophages to the M2 type, ultimately altering the pro‐inflammatory microenvironment. Further investigation of the treatment mechanism indicates that Rh‐GFFYE activates the PI3K/AKT/mTOR signaling pathway to reduce oxidative stress and inhibits the NF‐κB and STAT3 signaling pathways to affect inflammation and macrophage polarization. In conclusion, the rhein‐loaded nanoplatform alleviates RIR injury by modulating the retinal microenvironment. The findings are expected to promote the clinical application of hydrophobic natural products in RIR injury‐associated eye diseases.
Quantized Neural Network via Synaptic Segregation Based on Ternary Charge‐Trap Transistors
Authors: Baek Yongmin , Bae Byungjoon , Yang Jeongyong , Lee Doeon , Lee Hee Sung , Park Minseong , Kim Taegeon , Kim Sihwan , Park Bo‐In , Yoo Geonwook , Lee Kyusang
Published: September 2023

Artificial neural networks (ANNs) are widely used in numerous artificial intelligence‐based applications. However, the significant amount of data transferred between computing units and storage has limited the widespread deployment of ANN for the artificial intelligence of things (AIoT) and power‐constrained device applications. Therefore, among various ANN algorithms, quantized neural networks (QNNs) have garnered considerable attention because they require fewer computational resources with minimal energy consumption. Herein, an oxide‐based ternary charge‐trap transistor (CTT) that provides three discrete states and non‐volatile memory characteristics are introduced, which are desirable for QNN computing. By employing a differential pair of ternary CTTs, an artificial synaptic segregation with multilevel quantized values for QNNs is demostrated. The approach establishes a platform that combines the advantages of multiple states and robustness to noise for in‐memory computing to achieve reliable QNN performance in hardware, thereby facilitating the development of energy‐efficient AIoT.
The mitochondrial tRNA MT‐TW m.5537_5538insT variant presents with significant intra‐familial clinical variability
Authors: Strasser Lauren , Doja Asif , Davila Jorge , Chakraborty Pranesh , Bourque Danielle K.
Published: September 2023

Mitochondrial disorders can present with a wide range of clinical and biochemical phenotypes. Mitochondrial DNA variants may be influenced by factors such as degree of heteroplasmy and tissue distribution. We present a four‐generation family in which 10 individuals carry a pathogenic mitochondrial variant (m.5537_5538insT, MT‐TW gene) with differing levels of heteroplasmy and clinical features. This genetic variant has been documented in two prior reports, both in individuals with Leigh syndrome. In the current family, three individuals have severe mitochondrial symptoms including Leigh syndrome (patient 1, 100% in blood), MELAS (patient 2, 97% heteroplasmy in muscle), and MELAS‐like syndrome (patient 3, 50% heteroplasmy in blood and 100% in urine). Two individuals have mild mitochondrial symptoms (patient 4, 50% in blood and 67% in urine and patient 5, 50% heteroplasmy in blood and 30% in urine). We observe that this variant is associated with multiple mitochondrial presentations and phenotypes, including MELAS syndrome for which this variant has not previously been reported. We also demonstrate that the level of heteroplasmy of the mitochondrial DNA variant correlates with the severity of clinical presentation; however, not with the specific mitochondrial syndrome.
Efficient Intersystem Crossing and Long‐lived Charge‐Separated State Induced by Through‐Space Intramolecular Charge Transfer in a Parallel Geometry Carbazole‐Bodipy Dyad
Authors: Liang Hui , Lu Manlin , Mahmood Zafar , Li Zheng , Chen Zeduan , Chen Guowei , Li Ming‐De , Huo Yanping , Ji Shaomin
Published: September 2023

The design of efficient heavy atom‐free triplet photosensitizers (PSs) based on through bond charge transfer (TBCT) features is a formidable challenge due to the criteria of orthogonal donor‐acceptor geometry. Herein, we propose using parallel (face‐to‐face) conformation carbazole‐bodipy donor‐acceptor dyads (BCZ‐1 and BCZ‐2) featuring through space intramolecular charge transfer (TSCT) process as efficient triplet PS. Efficient intersystem crossing (ΦΔ=61 %) and long‐lived triplet excited state (τT=186 μs) were observed in the TSCT dyad BCZ‐1 compared to BCZ‐3 (ΦΔ=0.4 %), the dyad involving TBCT, demonstrating the superiority of the TSCT approach over conventional donor‐acceptor system. Moreover, the transient absorption study revealed that TSCT dyads have a faster charge separation and slower intersystem crossing process induced by charge recombination compared to TBCT dyad. A long‐lived charge‐separated state (CSS) was observed in the BCZ‐1 (τCSS=24 ns). For the first time, the TSCT dyad was explored for the triplet‐triplet annihilation upconversion, and a high upconversion quantum yield of 11 % was observed. Our results demonstrate a new avenue for designing efficient PSs and open up exciting opportunities for future research in this field.
Late‐stage Ligand Modification After Coordination Strengthens Stereoselectively Self‐Assembled Hemiaminal Ether Complexes
Authors: Raje Sakthi , Koner Abhishek , Ghosh Suchismita , Butcher Ray J. , Mathivathanan Logesh , Sundararajan Mahesh , Angamuthu Raja
Published: September 2023

Fragile hemiaminal ether linkages present in the backbone of koneramines (LROR’), tridentate ligands, bound to copper(II) in stereoselectively self‐assembled syn‐[Cu(LROR’)X2] complexes were transformed into sturdy methylene linkages to make corresponding rac‐[Cu(LRH)Cl2] complexes by late‐stage ligand modification after coordination with the retention of coordination sphere. The generality of stereoselective self‐assembly of koneramine complexes is shown by utilising a number of metal ions, anions, amines, alcohols and thiols with complete characterisations.
A Structural Perspective on Prussian Blue Analogues for Aqueous Zinc‐Ion Batteries
Authors: Li Min , Maisuradze Mariam , Sciacca Rosalinda , Hasa Ivana , Giorgetti Marco
Published: September 2023

Aqueous zinc‐ion batteries (AZIBs), have been identified as one of the most promising aqueous rechargeable metal‐ion batteries (ARMIBs) for grid scale electrochemical energy storage application, and as such have received much attention by virtue of their unique properties including the high abundance of metallic zinc resources, their intrinsic safety, and cost effectiveness. Among the cathode materials used in AZIBs, Prussian Blue Analogues (PBAs) represent the most promising active materials in view of their improved cyclability and rate performance. Here, we provide a comprehensive review on recent progress on AZIBs obtained using PBAs cathodes with a particular focus on the present understanding of the structure‐property correlation of different PBAs, which in turn guides further developments of improved cathode materials and optimization strategies to ensure an extended cyclability and capacity retention.
Energie‐„Dissipation”︁ in der Strahlenchemie
Authors: Burton Milton
Published: September 2023

Das englische Wort „dissipation”︁ im Titel wurde nicht übersetzt, um seine Doppeldeutigkeit zu erhalten; es soll verschiedene Aspekte des Schicksals der adsorbierten Energie in der Strahlenchemie ausdrücken. Unter den Mechanismen der Strahlenchemie findet man auch solche, die charakteristisch für die Photochemie, die Chemie elektrischer Entladungen und rein thermische Reaktionen sind.

Die Primärvorgänge der Energieübertragung umfassen Ionisation (gefolgt von Neutralisation) und Anregung von Molekeln zu verschiedenen Energiezuständen. Solche Zustände können sich innermolekular umwandeln, zersetzen oder Ionisation bzw. Anregung übertragen; das Verhalten dieser Zustände kann durch den Aggregationszustand des Systems, seine Reinheit und seine spezifisch chemische Struktur modifiziert werden.

Ein Merkmal, das die Strahlenchemie mit dem engeren Gebiet der Photochemie gemeinsam hat, ist die geringere chemische Wirkung der absorbierten Energie auf den flüssigen Zustand. Diese Erscheinung läßt sich zum Teil auf den Franck‐Rabinowitch‐Käfigeffekt zurückführen; des weiteren kommt ein Einfluß der Dichte auf die Struktur und das chemische Verhalten der primär ionisierten oder angeregten Komplexe ins Spiel.

Darüberhinaus können im flüssigen Zustand ganze Domänen von Lösungsmittelmolekeln an der Übertragung von Ionisation oder Anregung teilnehmen, woraus sich ein Schutz der primär angeregten Spezies und eine mögliche Strahlensensibilisierung der Acceptormolekel herleitet. Eine Strahlensensibilisierung der Acceptormolekel schützt jedoch nicht notwendigerweise die Donormolekel vor Zerfall; der Donor kann sich in einem angeregten Zustand befinden, der mit dem Zerfallsprozeß nichts zu tun hat.
Abtrennung und Bestimmung kurzlebiger Isotope
Authors: Strassmann F.
Published: September 2023

Ausbeutebestimmungen bei der Uranspaltung scheitern oft am Zeitbedarf der jeweiligen Methode, wenn es sich um kurzlebige Primärprodukte handelt. Von den Forderungen eines möglichst geringen Zeitbedarfs und einer sauberen Trennung und Isolierung ausgehend, wurden Methoden, die aus der klassischen Radiochemie bekannt sind, auf ihre Anwendbarkeit bei Produkten der Kernspaltung geprüft. Direkte und indirekte Bestimmungen unter Ausnutzung des radioaktiven Rückstoßes, sowie elektrolytischer Reduktion und Oxydation wurden unter Benutzung von Modellsubstanzen durchgeführt, da vorläufig eine Strahlenquelle geeigneter Leistungsfähigkeit noch nicht zur Verfügung steht.
Altersbestimmung an Gneisen des Simplonmassivs
Authors: Noddack W. , Zeitler G. , Menge P.
Published: September 2023

Die Einstufung der riesigen Gneismassen der Schweizer Alpen in die geologische Zeitskala bereitet große Schwierigkeiten. Zur Klärung dieser Frage werden einige Gneisproben aus dem Simplonmassiv nach der Kalium‐Argon‐Methode untersucht. Aus dem analytisch ermittelten Ar/40 K‐Verhältnis wird das geologische Alter berechnet und mit geologischen Altersangaben verglichen.
Die Austauschreaktion SO2 ⇌ H2*SO4 in homogener Gasphase
Authors: Erichsen L. V. , Borger W.
Published: September 2023

Zur Untersuchung der Austauschreaktion zwischen SO2 und H*2SO4 wurden entsprechende Meßeinrichtungen und Arbeitsmethoden entwickelt. Die mit dieser Anordnung durchgeführten Versuche zeigten, daß die Gleichung für Isotopen‐Austauschreaktionen nach McKay für das vorliegende System erfüllt ist. Die Versuche ergaben einen Anstieg der Reaktionsgeschwindigkeit mit zunehmender Temperatur bis zu etwa 280‐300°C, anschließend mit weiter steigender Temperatur ein Absinken auf ein ganz ausgeprägtes Minimum und von etwa 370°C an eine erneute Zunahme der Reaktionsgeschwindigkeit mit der Temperatur. Dieser eigenartige Effekt konnte schließlich dadurch erklärt werden, daß in den untersuchten Temperatur‐bereich die Dissoziation der Schwefelsäure fällt, wodurch das intakte H*2SO4 aus dem System verschwindet und sich dafür entsprechende Mengen *SO3 und H2O bilden. Dieses Phänomen bewirkt, daß der Austausch in dem untersuchten System, je nach dem Temperaturbereich, auf zwei verschiedenen Wegen erfolgt: bei niedrigeren Temperaturen als Austausch mit der Schwefelsäuremolekel uud bei höheren Temperaturen unter Beteiligung der Schwefeltrioxydmolekel. Das Auftreten eines Maximums bzw. Minimums der Reaktionsgeschwindigkeit ergibt sich dann aus der Überlagerung beider Austauscheffekte. Weitere Untersuchungen hierzu werden folgen.
Über die Zählung von Radioisotopen metallischer Elemente in flüssigen Szintillatoren
Authors: Erdtmann Gerhard , Herrmann Günter
Published: September 2023

Es wurden folgende Möglichkeiten untersucht, in wäßriger Lösung vorliegende Radioisotope metallischer Elemente in flüssige Szintillatoren zu überführen: 1. Vermischen der wäßrigen Lösung mit einem dioxan‐haltigen flüssigen Szintillator zu einem homogenen System; 2. Herstellung einer stöchiometrischen, toluollöslichen Verbindung, z.B. eines Metallsalzes einer Fettsäure; 3. Extraktion in Toluol durch einen Überschuß eines Extraktionsmittels; 4. Emulgieren der wäßrigen Lösung mit dem flüssigen Szintillator. Für kleine Volumina (bis etwa 1 ml) wäßrige Lösungen ist das vierte Verfahren am günstigsten, wobei hochdisperses Siliciumdioxyd als thixotropes Reagens benutzt wird. Größere Lösungsvolumina werden am besten nach dem dritten Verfahren behandelt. Von den untersuchten Extraktionsmitteln sind Tri‐, Di‐ und Mono‐n‐Butylphosphat, Di‐(2‐Äthylhexyl)‐phosphat, Tri‐n‐octylphosphinoxyd und Tri‐iso‐octylamin brauchbar, während 8‐Oxychinolin, Acetylaceton und Thenoyltrifluoraceton zu starke Löschung ergeben. Das zweite Verfahren ist demgegenüber umständlich, während bei der ersten Methode die Volumina an wäßriger Lösung wegen der Löschung und der Entmischung insbesondere in sauren Lösungen auf 0,2‐0,5 ml begrenzt sind.
Substituierte p‐Oligophenylene als Solute für flüssige Szintillatoren
Authors: Nay Uwe , Eichhoff Hans‐Joachim , Herrmann Günter , Wirth Hermann O.
Published: September 2023

Die relativen Impulshöhen flüssiger Szintillatoren mit methyl‐ und methoxyl‐substituierten p‐Quaterphenylen, p‐Quinquephenylen und p‐Sexiphenylen als Solute wurden gemessen. Die Verbindungen ergeben fast alle gute Szintillatoren; die günstigsten Eigenschaften haben die Derivate des p‐Quaterphenyls, während die p‐Quinque‐ und p‐Sexiphenyle demgegenüber keine entscheidenden Vorzüge bieten. Einige der untersuchten Verbindungen sind in der Impulshöhe den bekannten Soluten zumindest gleichwertig. Die ausgezeichnete Löslichkeit und die bemerkenswerte Stabilität macht sie letzteren überlegen.
Actions intermoléculaires dans les gaz comprimés
Authors: Vodar B.
Published: September 2023

Les actions intermoléculaires qui interviennent dans tous les fluides denses, sont particulièrement bien révélées par les études sur les gaz comprimés, pour lesquels une forte variation des distances intermoléculaires est obtenue pour des pressions relativement modérées. Dans la présente communication on passera en revue quelques résultats récents obtenus au Laboratoire des Hautes Pressions:

Dans l'étude de la viscosité des gaz un appareil à écoulement capillaire à été utilisé jusqu'à des pressions de l'ordre de 5000 bars sur l'azote; une comparaison entre le comportement de ce gaz et de celui de l'argon par rapport à la théorie d'Enskog fait ressortir des divergences importantes. En ce qui concerne la conductivité thermique, des mesures jusqu'à des températures atteignant 700 °C seront présentées pour H2O, D2O et CO2 et l'argon; la théorie d'Enskog est d'autant mieux suivie que la température est plus élevée, et la relation de Vargaftik est assez convenablement vérifiée.

L'étude spectroscopique des interactions moléculaires a donné quelques renseignements sur les forces intermoléculaires et le mécanisme des perturbations.

On rappellera comment le modèle d'un complexe de choc explique certains des aspects des spectres infrarogues observés (dans les mélanges de molécules polaries avec des molécules non polaires), par l'intervention au sein du complexe des potentiels d'orientation.

Une éude détaillée de l'élargissement et du déplacement des raies atomiques aux pressions moyennes a conduit à l'observation d'un effet isotopique et d'un effet de température qui suggèrent l'intervention de forces répulsives d'un certain type et d'une dynamique des chocs déctite par un modèle quantique selon la théorie de Schuller.