bluuebunny/crossref_metadata_2025 huggingface dataset:
Ground Water Contamination: Effects and Remedies
Authors: Hilili J. M. , Onuora D. I. , Hilili R. U. , Annah Arowosegbe Folusho , Onmonya Y. A. , Hilili M. H.
Published: January 2021

Studies on “ground water contamination : effects and remedies” have been conducted, in the light of these, field work studies in Obudu and Obanliku local Government Areas of Cross River State, South Eastern Nigeria, was conducted. Fifteen (15) locations of water for drinking and other domestic uses were carefully studied in the area, with their surface to water depth values recorded. Five(5) of the locations were at surface saturated water depressions(SWD), seven(7) were Hand dug wells(well), while three(3) were bore holes(BH). The physiochemical composition data compared with world Health Organization (WHO) standard shows that, the bore water was safer for drinking than the hand dug wells and surface water in saturated water depressions. Coliform count unite per 100ml of water, were detected in most of the locations in the saturated water depressions and hand dug wells, showing evidence of biogenic interference with the water. Coliform count unite per 100ml of water was not detected in any of the three bore holes, probably due to their depth distance from Biogenic activities. Phosphate and Nitrate levels were significantly above WHO standard in saturated water depressions and Hand dug wells, probably due to erosional and leaching actions of inorganic fertilizers from farm lands and waste from near dump site. It is important to note that most water borne diseases are as a result of ground water communication with contaminant, such as heavy metals, leachate from dump sites, pollutants from inorganic fertilizers, pith toilets   sea water intrusion etc., most boreholes are contaminated by these processes. This is one of the reasons for the increase in the rate of cancer in most developing countries. Hence, heavy metals are known to be carcinogenic to the human cells, and also can cause mutation. The remedies to these include:

The process of exploiting and storing ground water should be  done with all  safety  precautions, such as making sure  biochemical parameters  in water are in line with WHO standard

Thorough biochemical analysis and test for the presence of heavy metal contamination and coliform count and other contaminants should be done on ground water, before use for domestic and industrial purposes.

Surface depth measurement of recharge zones in boreholes should be carried out to ensure that borehole water is from confined aquifers that are safe for domestic and industrial uses.

Proper waste disposing system such as engineered toilet pits, engineered dump sites and effective management of electronic waste should be monitored and implemented

Where the purity of the water is not satisfactory, such water should be properly treated before used for drinking and other domestic purposes.
Construction of Corrupt Behavior Practices of Village Officials through Web Portals in Indonesia 2019
Authors: Triyono Agus
Published: January 2021

The role of online mass media in this period became very important in disseminating information to the public. Online media such as news.detik.com and jateng.tribunnews.com have become one of the media that has reported a lot about village funds. However, the two online masses have their styles in constructing village fund news in Central Java, especially concerning several corruption cases that involve village officials.

This study aims to analyze the construction of village officials behavior through the framing of the web portal 1 and web portal 2 in the corruption case of village funds in Central Java, Indonesia.

This research is a qualitative type with a descriptive approach. The data collection method used documentation study from the web portal 1 and web portal 2.

The research partisipants were the news content of web portal 1 and web portal 2 for the period 2019. The analysis used was the framing analysis model of Zhong Dang Pan and Gerald M. Kosicki.

The finding of this research is that the news from web portal 1 highlights the "how" and "why" aspects. Web portal 2 has more news about live news and is oriented in advance and actuality based on quick publication than web portal 1.

Conclusion: web portal 1 in explaining the corruption of village funds deeper than web portal 2. This news has influenced the behavior patterns of village officials in carrying out village government duties.
Nutritional and Consumers Behavior towards Street Foods
Authors: Verma Ruchi , Mishra Sunita
Published: January 2021

Street foods plays vital role for low and middle income group of urban peoples of developing countries, street foods meets food and nutritional requirements at very affordable prices for peoples all over the world. Mostly street foods are unhealthy foods, which is increased by high risk of contamination through physical, chemical and biological components which occurs a grave concern in the form of food safety and security. Street foods are nutritionally rich and these are rich source of carbohydrates and fats, eating which increases the risk of chronic non communicable diseases. Street foods may the increases risk of foodborne illnesses, which is the reason of food contamination through the microorganisms and so that food poisoning are developed. Due to lack of facilities, cheap raw materials, also lack of education and insufficient knowledge (GMP) of street food handlers, can cause foodborne diseases and chronic non-communicable diseases, and with which strongly influence on Food Safety, Nutritional Value and  health of school children’s and all  urban peoples of developing countries. To troubleshoot all these problems proper health authorities should regulate the marketing of street food products and start a proper training program for the urban street food handlers and school based street food handlers, which is related to food safety, food security, foodborne diseases and non communicable diseases. In addition, the inclusion of food safety and food security in school courses will provide opportunities for all peoples and school children’s to becomes aware about food safety, food security and nutrition. however, street foods are oftentimes an unhealthy diet and notwithstanding, street foods meet peoples dietary needs. Street food vending have occurred a vital public health issues and a major consideration to everybody. The objective of this study to describe nutritional issues of street foods to the diet, Nutritional Value of Street Foods, consumers eating habits and its impact on Health. It is necessary that, the standards suggested by the Codex Alimentarius Commission and WHO should be included, to contribute to nutritional security of street foods and public health.
Comparative Analysis and Regenerative Studies of Alkaline Modified Groundnut Shell as Adsorbent for the Removal of Oil Layer from Polluted Water
Authors: Ezenwa Okoro Sylvanus , Ogochukwu Nwabueze Henrietta
Published: January 2021

This work focuses on the comparative analysis and regenerative studies of alkaline modified groundnut shell as adsorbent for the removal of oil layer from water surface. The groundnut shell was carbonized at 800°C before chemical activation. Scanning Electron Microscope (SEM) and UV/VIS Spectrophotometer were used in characterizing the adsorbents. Batch adsorption studies were carried out to determine the effect of process conditions on the percentage removal. Regeneration studies was applied to investigate the reusability of the adsorbent after each batch of experiments. SEM characterization revealed that micro porous space on the surface of the adsorbent (groundnut shell) increased significantly after activation. The surface area of the composite increased from 28.5cm2 to 87.9cm2 after activation. pH of point zero charge ranging from  to  revealed negative charge predominance on the surface of the adsorbents and adsorption was found to be very fast at low pH due to strong electrostatic force between oil layer and ion diffusion on the adsorbent surface. The optimum adsorption time was found to be 100 minutes with 79.4% oil removal.at pH of 6.9. Regeneration of the adsorbent after each batch of experiments shows that the surface area remained intact at 77.8cm2 which is almost equal to the modified (unused) adsorbent. Experiments with the regenerated adsorbent shows that 84.89% of oil was removed at oil water ratio of 0.2g/100cm3 against 88.56% of oil removed using the modified adsorbent at the same oil water ratio.  Thus, the sorption process was feasible, spontaneous, rapid and showed high performance with a proven ability of the adsorbent to be regenerated after use. However, the present approach has the advantage of simplicity, less time consuming and most importantly, low cost considering the availability of groundnut shell at no cost.
Prevalence, Pattern and Monitoring of Adverse Drug Reaction in Tertiary Care Psychiatry Setting- A Hospital Based Study in South Kerala
Authors: Dharman Dhanya , Krishnan S. Parimala , Ravikumar K. G
Published: January 2021

Pharmacovigilance programs usually aim to gather information on the effect of prescribed drugs in the real world rather than in groups of short-lived and carefully selected clinical trial populations. Adverse drug reactions (ADR) associated with psychiatric medications may vary among different populations. As compared with other fields, in Kerala the research related to ADRs and Prescription patterns in psychiatry is scarce. A hospital based cross sectional observational study was undertaken in the Mental Health Centre, Trivandrum.  All psychiatric drugs were closely monitor for adverse drug reaction irrespective of their psychiatric diagnosis. CDSCO Suspected adverse drug reaction reporting form was  used for the documentation of adverse drug reaction and the causality assessment was  done with naranjo scale .The severity of ADR was assessed using Hartwing scale and Preventability assessment using Modified schumock. In this study it was found the highest incident of ADR was reported with risperidone (24%) followed by valproate (20.1%), clozapine (17%) etc. The patient in psychiatry cant identify the adverse effect due to the cognitive impairment. So special attention is necessary for psychiatric patient to find out the incidence of adverse drug reaction and provide the proper management to them.
Impact of COVID-19 on Cardiovascular Patients and Review of Current COVID-19 Treatment Strategies
Authors: Alfawaz Dalal A. , Alfawaz Mohammed , Almutawa Ali M.
Published: January 2021

Coronavirus disease of 2019 (COVID-19) has severely affected global health and caused a significant health burden worldwide, particularly in patients with cardiovascular insult. Worldwide, the COVID-19 confirmed cases number reached 81,658,440 cases with 1,802,206 deaths stated to the world health organization by January 1, 2021. Many risk factors, such as the elderly, diabetes, chronic kidney disease (CKD), and cardiovascular illness, like coronary disease, cardiomyopathy, and hypertension; put people at high vulnerability with COVID-19 infection. Many cardiovascular insults directly occur because of COVID-19 infection as myocarditis, pericarditis, heart failure, myocardial infarction, thromboembolic events, or arrhythmias. This review aims to shed light on different management modalities for COVID-19 and discuss the impact of COVID-19 on underlying cardiovascular comorbidities.  Our hope lies in the COVID-19 vaccine as the best promising plan against the pandemic with the antiviral medications. Till the availability of antiviral agents and effective vaccines, repurposing drugs therapy would continue to be the mainstream. Cardiovascular diseases may be caused by or precedent conditions in COVID-19 patients. The physicians and the medical staff should be up-to-date regarding probable complications with COVID-19.
Natural Hazards and Complex Disasters
Authors: Singh Simron J.
Published: January 2021

This entry reviews key trends in disaster research over the past century, in terms of definitions, causes, impacts, and current practices in dealing with disasters. The second part uses the case of the Nicobar Islands in the aftermath of the 2004 tsunami and shows how an indigenous, subsistence, island community of hunters and gatherers has been transformed into an aid‐dependent, monetary economy embedded in the regional market. The new consumer profile brings in a high potential for social conflict in terms of access to resources and land, leadership, social coherence, family structure, and the need for continued aid flow. The case illustrates the metabolic collapse of an island socioecological system, and reveals the inherent metabolic risks and traps in terms of the islands' sustainable future, both ecologically and socially, and the role of disaster response in driving them to their biophysical limits as islands in the aftermath.
Gender and Domestic Workers
Authors: Lowrie Claire
Published: January 2021

The term “domestic servant” is often perceived to be synonymous with “woman.” However, in particular cultural contexts and time periods, paid domestic labor performed in private homes was a role associated with men. The “houseboy,” for example, was an integral part of colonial households in Africa, Southeast Asia, and the Pacific. In the contemporary era, domestic service as an occupation is undergoing a resurgence and is overwhelmingly a feminized sector of work that includes a high proportion of migrant workers. The revival of the occupation has been attributed to the persistence of inequalities, particularly those stemming from the legacy of colonialism and those related to the economic forces of globalization. As their labor is performed behind closed doors, domestic workers are vulnerable to exploitation and abuse. In recent years, domestic workers have engaged in transnational labor activism with the goal of regulating wages and conditions across the sector.
Gender and Climate Change
Authors: Jolly Margaret
Published: January 2021

Interrogating the relation between gender and climate change is a burgeoning transdisciplinary field. Although gender and the environment were intrinsically linked in the scholarship and politics of ecofeminism from the 1970s, early research, policy, and practice on climate change were often gender blind. Researchers and activists predominantly from the global South insisted that gender inequalities alongside class and race were crucial in the divergent experiences of climate change. They revealed how women were more vulnerable to the impacts of climate change, in their daily lives and in extreme weather events. Later analyses qualified the prevalent portrait of women as the most vulnerable victims by highlighting women's agency, resilience, and resistance. Critical studies have analyzed the gendered inequalities in dominant discourses about climate change and challenged the bipolar emphasis on male/female and human/nonhuman. The urgency of the climate crisis has heightened the need to deeply connect gender justice and climate justice.
Matter
Authors: Witmore Christopher
Published: January 2021

Matter is unruly. The word is both a convenient catch‐all for the ultimate stuff of existence and a specific ingredient lodged in the substratum of the real. Matter is regarded both as an inert basal layer embedded in a hierarchy of bodies and a quivering multitude obscured by a taxonomic distinction between the animate and inanimate. Materialism holds no monopoly over matter, as it also comes in idealist strains. From Marxism and material culture studies to idealism and vital materialism to indigenous ontologies and science studies, this entry explores matter's varieties and associations within anthropology and raises questions as to its limits.
Fashion and Dress, Anthropology of
Authors: Craik Jennifer
Published: January 2021

Anthropological approaches to fashion and dress have largely been seen as an illustration of the “holistic” approach of anthropology to exploring diverse aspects of human culture, including biological, sociological, and historical factors. Early anthropology included references to dress and decoration as markers of the exotic nature of “native” peoples. Dress indicated a visible sign of a group whose clothing habits suited particular ways of life of precivilized and non‐European people. It was usually regarded as unchanging and traditional. Fashion was seen as a product of capitalist and consumerist cultures of modernity with its impetus for continuous change and reinvention. Structural anthropologists interpreted dress as a form of decoration and display as well as a means of protection and a symbol of hierarchy and status. Cultural anthropologists explored individuality, choice, and stylistic variations within dress codes. Recent analyses have adopted the interdisciplinary approaches of cultural studies.
An analytical expression for R50% dependent on PTV surface area and volume: A cranial SRS comparison
Authors: Desai Dharmin D. , Johnson E. L. , Cordrey Ivan L.
Published: January 2021

The intermediate dose spill for a stereotactic radiosurgery (SRS) plan can be quantified with the metric R50%, defined as the 50% isodose cloud volume (VIDC50%) divided by the volume of the planning target volume (PTV). By coupling sound physical principles with the basic definition of R50%, we derive an analytical expression for R50% for a spherical PTV. Our analytical expression depends on three quantities: the surface area of PTV (SAPTV), the volume of PTV (VPTV), and the distance of dose drop‐off to 50% (Δr). The value of ∆r was obtained from a simple set of cranial phantom plan calculations. We generate values from our analytical expression for R50% (R50%Analytic) and compare the values to clinical R50% values (R50%Clinical) extracted from a previously published SRS data set that spans the VPTV range from 0.15 to 50.1 cm3. R50%Analytic is smaller than R50%Clinical in all cases by an average of 15% ± 7%, and the general trend of R50%Clinical vs VPTV is reflected in the same trend of R50%Analytic. This comparison suggests that R50%Analytic could represent a theoretical lower limit for the clinical SRS data; further investigation is required to confirm this. R50%Analytic could provide useful guidance for what might be achievable in SRS planning.
Highly Breathable and Stretchable Strain Sensors with Insensitive Response to Pressure and Bending
Authors: Liu Zekun , Zheng Yan , Jin Lu , Chen Kaili , Zhai Heng , Huang Qiyao , Chen Zhongda , Yi Yangpeiqi , Umar Muhammad , Xu Lulu , Li Gang , Song Qingwen , Yue Pengfei , Li Yi , Zheng Zijian
Published: January 2021

Wearable tensile strain sensors have aroused substantial attention on account of their exciting applications in rebuilding tactile inputs of human and intelligent robots. Conventional such devices, however, face the dilemma of both sensitive response to pressure and bending stimulations, and poor breathability for wearing comfort. In this paper, a breathable, pressure and bending insensitive strain sensor is reported, which presents fascinating properties including high sensitivity and remarkable linearity (gauge factor of 49.5 in strain 0–100%, R2 = 99.5%), wide sensing range (up to 200%), as well as superior permeability to moisture, air, and water vapor. On the other hand, it exhibits negligible response to wide‐range pressure (0–100 kPa) and bending (0–75%) inputs. This work provides a new route for achieving wearing comfortable, high‐performance, and anti‐jamming strain sensors.
Design Strategy for Transformative Electronic System toward Rapid, Bidirectional Stiffness Tuning using Graphene and Flexible Thermoelectric Device Interfaces
Authors: Byun Sang‐Hyuk , Kim Choong Sun , Agno Karen‐Christian , Lee Simok , Li Zhuo , Cho Byung Jin , Jeong Jae‐Woong
Published: January 2021

Electronics with tunable shape and stiffness can be applied in broad range of applications because their tunability allows their use in either rigid handheld form or soft wearable form, depending on needs. Previous research has enabled such reconfigurable electronics by integrating a thermally tunable gallium‐based platform with flexible/stretchable electronics. However, supercooling phenomenon caused in the freezing process of gallium impedes reliable and rapid bidirectional rigid–soft conversion, limiting the full potential of this type of “transformative” electronics. Here, materials and electronics design strategies are reported to develop a transformative system with a gallium platform capable of fast reversible mechanical switching. In this electronic system, graphene is used as a catalyst to accelerate the heterogeneous nucleation of gallium to mitigate the degree of supercooling. Additionally, a flexible thermoelectric device is integrated as a means to provide active temperature control to further reduce the time for the solid–liquid transition of gallium. Analytical and experimental results establish the fundamentals for the design and optimized operation of transformative electronics for accelerated bidirectional transformation. Proof‐of‐concept demonstration of a reconfigurable system, which can convert between rigid handheld electronics and a flexible wearable biosensor, demonstrates the potential of this design approach for highly versatile electronics that can support multiple applications.
Observing and Understanding the Corrosion of Silver Nanowire Electrode by Precursor Reagents and MAPbI3 Film in Different Environmental Conditions
Authors: Yan Zheng , Chen Hongye , Li Min , Wen Xiaoyan , Yang Yingping , Choy Wallace C. H. , Lu Haifei
Published: January 2021

Since metal electrode is an important component in the perovskite solar cells, which can be used as back contact, transparent electrode, and the transparent interlayer of tandem devices, the corrosion of metal electrode by perovskite film, should be understood. Here, the corrosion of conventional reagents of organic–inorganic perovskite material, i.e., CH3NH3X (MAX) and PbX2, X = I, Br, and Cl, against silver nanowire (AgNW) based transparent electrode are investigated under four different environments, i.e., nitrogen protection, light irradiation, oxygen exposure, and moisture exposure, separately. The corrosion process is inspected by monitoring the time‐dependent resistance variation of the electrode coated by the film of precursor reagent. In addition, the perovskite film of CH3NH3PbI3 (MAPbI3) is also coated on the silver nanowire electrode without or with the hole transporting layer of poly(3,4‐ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT:PSS) or nanostructured CuSCN for understanding the corrosion process under different environmental conditions. The experimental results presented in this paper would be helpful to the understanding of metal electrode stability in perovskite solar cells.
Shape Transformation Mechanism of Gallium–Indium Alloyed Liquid Metal Nanoparticles
Authors: He Jing , Shi Fenglei , Wu Jianbo , Ye Jian
Published: January 2021

Eutectic gallium indium (EGaIn) spherical liquid metal nanoparticles (NPs) can transform to gallium oxide hydroxide (GaOOH) microrods in water. Nevertheless, the mechanism of this process still remains unrevealed. In this work, the whole shape transformation process of EGaIn NPs is investigated via monitoring the change of NPs’ composition and morphology. Gallium (Ga) element in EGaIn NPs can be oxidized to form gallium oxide, which further reacts with water to generate micrometer‐sized GaOOH crystals. This chemical variation occurs gently at room temperature and is accelerated by heating. With continuous consumption of Ga element, indium condenses to form individual NPs. The dynamic temperature‐dependent dissolution and precipitation of GaOOH microrods in water are further demonstrated. Deep understanding of the mechanism of EGaIn NPs’ shape transformation would provide more approaches to control the surface and bulk properties of NPs for potential applications in various fields including soft robotics, wearable devices, and nanomedicine.
Pushing the Study of Point Defects in Thin Film Ferrites to Low Temperatures Using In Situ Ellipsometry
Authors: Tang Yunqing , Chiabrera Francesco , Morata Alex , Garbayo Iñigo , Alayo Nerea , Tarancón Albert
Published: January 2021

Unveiling point defects concentration in transition metal oxide thin films is essential to understand and eventually control their functional properties, employed in an increasing number of applications and devices. Despite this unquestionable interest, there is a lack of available experimental techniques able to estimate the defect chemistry and equilibrium constants in such oxides at intermediate‐to‐low temperatures. In this study, the defect chemistry of a relevant material such as La1−xSrxFeO3−δ (LSF) with (x = 0.2, 0.4 and 0.5 (LSF20, LSF40 and LSF50 respectively) is obtained by using a novel in situ spectroscopic ellipsometry approach applied to thin films. Through this technique, the concentration of holes in LSF is correlated to measured optical properties and its evolution with temperature and oxygen partial pressure is determined. In this way, a systematic description of defect chemistry in LSF thin films in the temperature range from 350 °C to 500 °C is obtained for the first time, which represents a step forward in the understanding of LSF20, LSF40 and LSF50 for emerging low temperature applications.
High‐Power Broadband NIR LEDs Enabled by Highly Efficient Blue‐to‐NIR Conversion
Authors: Basore Endale Tamiru , Wu Huajun , Xiao Wenge , Zheng Guojun , Liu Xiaofeng , Qiu Jianrong
Published: January 2021

Phosphor‐converted light‐emitting diodes (pc‐LEDs) with broadband near‐infrared (NIR) emission have emerged as compact light sources for portable NIR spectroscopy. However, the associated broadband NIR phosphors suffer from low quantum efficiency (QE) and severe thermal quenching. Here the realization of highly efficient (internal QE ≈ 90%) and nearly zero‐thermal‐quenching broad NIR emission in Cr3+ and Yb3+ codoped Gd3Sc1.5Al0.5Ga3O12 (GSGG) via efficient energy transfer from Cr3+ to Yb3+ is reported, whereby a high‐performance NIR pc‐LED is obtained that can generate ultra‐broad‐band NIR emission covering the whole range of 700−1100 nm with high output power (50 mW at a current of 100 mA) and high photoelectric efficiency (24% at a current of 10 mA). The results not only demonstrate that Cr3+ and Yb3+ codoped GSGG has great potential for compact NIR light sources, but also indicate that the strategy of energy transfer can be exploited for developing new NIR phosphors with both high QE and thermal stability.
Toward Full‐Color Tunable Chiroptical Electrothermochromic Devices Based on a Supramolecular Chiral Photonic Material
Authors: Jiang Shun‐An , Chang Jia‐Lun , Lin Jyun‐Wei , Zhang Yan‐Song , Mo Ting‐Shan , Lin Jia‐De , Lee Chia‐Rong
Published: January 2021

Traditional electrochromic devices change the color of electrochromic materials by mainly transforming the absorption band of the materials electrically, which leads to low schedulable color selection and color performance of such materials after electrochromism. Although the addition of an interference‐enhanced nanocavity can improve this issue, achieving full‐color controllability on a single electrochromic device is still a huge challenge. This study first demonstrates a near‐full‐color tunable chiroptical electrothermochromic device using a supramolecular chiral photonic material called ferroelectric liquid crystal (FLC)‐doped cholesteric liquid crystal (CLC) (FLC‐CLC). Experimental results show that the pitch of the CLC can be elongated significantly by doping a low concentration of FLC (≈4 wt%) such that the photonic bandgap (PBG) redshifts from blue to the shortwave near‐infrared region at near room temperature. Based on this fascinating feature, the PBG of the FLC‐CLC can be tuned electrically over the entire visible region with high color performance at near room temperature in a low‐voltage range (≤3 V) via the efficient electrothermal effect of the indium‐tin‐oxide‐coated substrate of the sample. Two potential low‐voltage tunable applications based on electrothermochromic FLC‐CLC materials, namely, a broadband tunable laser and a near‐full‐color tunable coaxial microfibric textile, are demonstrated in the study.
Effective Transmission Modulation at Telecommunication Wavelengths through Continuous Metal Films Using Coupling between Borophene Plasmons and Magnetic Polaritons
Authors: Nong Jinpeng , Feng Fu , Min Changjun , Yuan Xiaocong , Somekh Michael
Published: January 2021

Optical modulation has been recognized as one of the most important operations in photonics. The use of 2D materials that support highly confined plasmonic modes allows one to manipulate light at the extreme subwavelength scale, thus significantly shrinking the size of the modulator, with potential for major advances in the state of art of existing devices. Here, a prototype plasmonic modulator is theoretically presented for the effective transmission modulation through a continuous metal film enabled by the strong coupling between anisotropic borophene surface plasmonic (BSP) modes and magnetic polaritons (MP) modes. Simulations reveal that plasmonic absorption in borophene within the grating slits can efficiently suppress the extraordinary optical transmission induced by the MP mode, resulting in the effective transmission modulation. By dynamically tuning the borophene electron density to decouple or couple BSP mode with MP mode, high modulation efficiency of 98.6% at 1550 nm can be achieved for borophene along both crystal axes, indicating excellent performance of the designed modulator via such mechanism. These results illustrate the potential of strong BSP–MP coupling as a promising strategy to realize the transmission modulation for optoelectronic applications.
Applications of Discrete Synthetic Macromolecules in Life and Materials Science: Recent and Future Trends
Authors: Aksakal Resat , Mertens Chiel , Soete Matthieu , Badi Nezha , Du Prez Filip
Published: January 2021

In the last decade, the field of sequence‐defined polymers and related ultraprecise, monodisperse synthetic macromolecules has grown exponentially. In the early stage, mainly articles or reviews dedicated to the development of synthetic routes toward their preparation have been published. Nowadays, those synthetic methodologies, combined with the elucidation of the structure–property relationships, allow envisioning many promising applications. Consequently, in the past 3 years, application‐oriented papers based on discrete synthetic macromolecules emerged. Hence, material science applications such as macromolecular data storage and encryption, self‐assembly of discrete structures and foldamers have been the object of many fascinating studies. Moreover, in the area of life sciences, such structures have also been the focus of numerous research studies. Here, it is aimed to highlight these recent applications and to give the reader a critical overview of the future trends in this area of research.
A High‐Performance Flexible Broadband Photodetector Based on Graphene–PTAA–Perovskite Heterojunctions
Authors: Zhou Guigang , Sun Rui , Xiao Yan , Abbas Ghulam , Peng Zhengchun
Published: January 2021

Organometal halide perovskites (CH3NH3PbI3−xClx) have received considerable attention in the field of optoelectronics due to their strong light absorption and long carrier lifetime. However, the performance such as response speed, responsivity, and stability of such detectors still need to be improved. In this paper, a flexible photodetector (PD) composed of multilayered structure of graphene–poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine] (PTAA)–perovskite‐poly(methyl methacrylate) (PMMA) is proposed. The PD can detect a wide wavelength range from ultraviolet to near infrared. The PD shows a high detectivity of ≈1013 Jones and a responsivity of 105 A W−1 at 360 nm. More importantly, the device also shows a high bending durability, fast response time, and good stability in air due to the protection of the PMMA layer. The facile and low‐cost fabrication of the flexible perovskite‐based hybrid photodetector indicates the mass production for the potential application in sensitive broadband photodetection.
Core–Shell Single‐Nanowire Photodetector with Radial Carrier Transport: an Opportunity to Break the Responsivity‐Speed Trade‐off
Authors: Cao Guoyang , Chen Guoqing , Li Xiaofeng
Published: January 2021

The trade‐off between the responsivity and response speed is a key limiting factor for the realization of high‐performance photodetectors. Here, a core–shell single‐nanowire structure with radial carrier transport is proposed for the possibility of breaking this trade‐off. Taking multilayer molybdenum disulfide (MoS2) as the exemplified material, the photoelectric responses of the core–shell nanowire MoS2 photodetector are theoretically predicted and numerically simulated. Thanks to the enhanced light absorptivity and ultra‐short transmission distance of carriers in the nanowire, the photodetector achieves an ultrahigh responsivity with sustaining a short response time. In a wide range of visible spectrum, the responsivity, response time, and specific detectivity of the nanowire photodetector reach 104 A W−1, 230 ps, and 1012 Jones, respectively, according to the optoelectronic simulation. The responsivity‐bandwidth product is predicted up to ≈1013 Hz A W−1, which is at least three orders of magnitude higher than that of the conventional MoS2‐based photodetectors. It is believed that the nanowire design provides a new scheme for promoting the development of the high‐performance photodetectors.
Solution‐Processed High‐Performance ZnO Nano‐FETs Fabricated with Direct‐Write Electron‐Beam‐Lithography‐Based Top‐Down Route
Authors: Tiwale Nikhil , Senanayak Satyaprasad P. , Rubio‐Lara Juan , Prasad Abhinav , Aziz Atif , Alaverdyan Yury , Welland Mark E.
Published: January 2021

Zinc oxide (ZnO) has been extensively investigated for use in large‐area electronics; in particular, the solution‐processing routes have shown increasing promise towards low‐cost fabrication. However, top‐down fabrication approaches with nanoscale resolution, towards aggressively scaled device platforms, are still underexplored. This study reports a novel approach of direct‐write electron‐beam lithography (DW‐EBL) of solution precursors as negative tone resists, followed by optimal precursor processing to fabricate micron/nano‐field‐effect transistors (FETs). It is demonstrated that the mobility and current density of ZnO FETs can be increased by two orders of magnitude as the precursor pattern width is decreased from 50 µm to 100 nm. These nano‐FET devices exhibit field‐effect mobility exceeding ≈30 cm2 V−1 s−1 and on‐state current densities reaching 10 A m−1, the highest reported so far for direct‐write precursor‐patterned nanoscale ZnO FETs. Using atomic force microscopy and parametric modeling, the origin of such device performance improvement is investigated. The findings emphasize the influence of pre‐decomposition nanoscale precursor patterning on the grain morphology evolution in ZnO and, consequently, open up large‐scale integration, and miniaturization opportunities for solution‐processed, high‐performance nanoscale oxide FETs.
Revealing Charge Transport and Device Operations of Organic Ambipolar Transistors and Inverters by Four‐Probe Measurement
Authors: Liu Chenning , Dai Fuhua , Liu Baiquan , Wei Huan , Chen Pingan , Hu Yuanyuan , Wu Jin , Liu Chuan
Published: January 2021

Detecting and understanding ambipolar charge accumulation and transport are essential for constructing ambipolar organic field‐effect transistors (OFETs). However, it is difficult to determine carrier motion using general electrical tests. Here, the generalized gated four‐probe (G‐GFP) technique is extended to ambipolar transistors made of diketopyrrolopyrrole‐thieno[3,2‐b]thiophene copolymer (DPPT‐TT), and the motion of the internal carrier during operation is investigated. The evolution of the local potential is monitored in the channel to establish a clear and quantitative picture of accumulation and transport for two types of carriers during device operation. Both simulation and experimental results verify that G‐GFP is a suitable and accessible approach for extracting the device mobility of ambipolar transistors. An ambipolar device with a G‐GFP structure can function as a single‐OFET inverter, demonstrating that G‐GFP can serve as an effective tool for ambipolar transistor analysis, while simultaneously facilitating the implementation of logic functions.
Recent Advances in Heterostructured Anode Materials with Multiple Anions for Advanced Alkali‐Ion Batteries
Authors: Park Gi Dae , Park Jin‐Sung , Kim Jin Koo , Kang Yun Chan
Published: January 2021

As rechargeable battery technology continues to advance, the development of advanced electrode materials is becoming increasingly crucial to meet the emerging demand for electrochemical energy storage devices with higher energy and power densities. However, progress in anode materials has been sluggish and graphite is still widely applied in commercial rechargeable batteries. Alloying and conversion reaction‐based anode materials, including Si, Sn, metal oxides, and metal chalcogenides, have been widely investigated as they exhibit much higher theoretical capacities than carbonaceous materials. However, they exhibit several intrinsic limitations, such as large volume change, low electrical conductivity, and high voltage hysteresis. Recently, the construction of heterostructures for anode materials has received increasing attention as it is an effective strategy to greatly enhance the capacity and rate performance by forming built‐in electric fields at the heterointerfaces, which can lower the activation energy for surface reactions. This review introduces the recent progress in the development of heterostructured anode materials with an emphasis on metal compounds with multiple anions and various interpretations of the origin of their superior electrochemical properties in rechargeable alkali‐ions (Li+, Na+, and K+) batteries. The challenges and future outlook of advanced heterostructured anode materials research are discussed at the end of this review.
Organic π‐Conjugated Polymers as Photocathode Materials for Visible‐Light‐Enhanced Hydrogen and Hydrogen Peroxide Production from Water
Authors: Oka Kouki , Winther‐Jensen Bjorn , Nishide Hiroyuki
Published: January 2021

The photo(electro)chemical reduction of water and oxygen to produce hydrogen (water‐splitting) and hydrogen peroxide, respectively, are well developed with inorganic semiconductors. In contrast, organic π‐conjugated polymers, especially precisely synthesized ones, have been extensively studied as photoharvesting and charge‐separating materials in dry photoelectron‐conversion devices, such as organic photovoltaic cells. However, the use of conjugated polymers as photocathodes; i.e., photoelectrocalatalytic reduction‐active materials in direct contact with aqueous electrolytes, has been less explored. This review describes the fundamentals of the electrochemistry of water and oxygen reduction, as well as organic semiconductor functions for photocathode activity in water, along with figures of merit for organic photocathodes used to practically produce hydrogen and hydrogen peroxide. Recent research on conjugated polymers in this field is then surveyed after briefly referring to early trial‐and‐error investigations using conventional conjugated polymers. Basic and very simple designs of robust polythiophene films are demonstrated as examples of successful materials which act as both visible‐light harvesters and catalysts for hydrogen evolution and the production of hydrogen peroxide, and as counterparts in combination with conventional oxygen‐evolution catalysts. Perspectives for this emerging field are also briefly provided.
On the Beneficial Impact of Li2CO3 as Electrolyte Additive in NCM523 ∥ Graphite Lithium Ion Cells Under High‐Voltage Conditions
Authors: Klein Sven , Harte Patrick , Henschel Jonas , Bärmann Peer , Borzutzki Kristina , Beuse Thomas , van Wickeren Stefan , Heidrich Bastian , Kasnatscheew Johannes , Nowak Sascha , Winter Martin , Placke Tobias
Published: January 2021

Lithium ion battery cells operating at high‐voltage typically suffer from severe capacity fading, known as ‘rollover’ failure. Here, the beneficial impact of Li2CO3 as an electrolyte additive for state‐of‐the‐art carbonate‐based electrolytes, which significantly improves the cycling performance of NCM523 ∥ graphite full‐cells operated at 4.5 V is elucidated. LIB cells using the electrolyte stored at 20 °C (with or without Li2CO3 additive) suffer from severe capacity decay due to parasitic transition metal (TM) dissolution/deposition and subsequent Li metal dendrite growth on graphite. In contrast, NCM523 ∥ graphite cells using the Li2CO3‐containing electrolyte stored at 40 °C display significantly improved capacity retention. The underlying mechanism is successfully elucidated: The rollover failure is inhibited, as Li2CO3 reacts with LiPF6 at 40 °C to in situ form lithium difluorophosphate, and its decomposition products in turn act as ‘scavenging’ agents for TMs (Ni and Co), thus preventing TM deposition and Li metal formation on graphite.
Dually‐Passivated Perovskite Solar Cells with Reduced Voltage Loss and Increased Super Oxide Resistance
Authors: Zhou Qin , Gao Yifeng , Cai Chunsheng , Zhang Zhuangzhuang , Xu Jianbin , Yuan Zhongyi , Gao Peng
Published: January 2021

In recent years, the power conversion efficiency (PCE) of perovskite solar cells (PSCs) has witnessed rapid progress. Nevertheless, the pervasive defects prone to non‐radiative recombination and decomposition exist at the surface and the grain boundaries (GBs) of the polycrystalline perovskite films. Herein, we report a comprehensive dual‐passivation (DP) strategy to effectively passivate the defects at both surface and GBs to enhance device performance and stability further. Firstly, a fluorinated perylene‐tetracarboxylic diimide derivative is permeated in the perovskite metaphase during antisolvent treatment, and then a fluorinated bulky aromatic ammonium salt is introduced over the annealed perovskite. The reduction of defect density can be unambiguously proved by the superoxide species generation/quenching reaction. As a result, optimized planar PSCs demonstrate a decreased open‐circuit voltages deficit from 0.47 to 0.39 V and the best efficiency of 23.80 % from photocurrent scanning with a stabilized maximum power output efficiency of 22.99 %. Without encapsulation, one typical device can maintain over 85 % of the initial efficiency after heating on a hot plate at 100 °C for 30 h under relative humidity (RH) of 70 %. When the device is aged under 30±5 % RH, over 97 % of its initial PCE is retained after 1700 h.
Visualizing Interfacial Jamming Using an Aggregation‐Induced‐Emission Molecular Reporter
Authors: Gu Pei‐Yang , Zhou Feng , Xie Ganhua , Kim Paul Y. , Chai Yu , Hu Qin , Shi Shaowei , Xu Qing‐Feng , Liu Feng , Lu Jian‐Mei , Russell Thomas P.
Published: January 2021

With the interfacial jamming of nanoparticles (NPs), a load‐bearing network of NPs forms as the areal density of NPs increases, converting the assembly from a liquid‐like into a solid‐like assembly. Unlike vitrification, the lineal packing of the NPs in the network is denser, while the remaining NPs can remain in a liquid‐like state. It is a challenge to determine the point at which the assemblies jam, since both jamming and vitrification lead to a solid‐like behavior of the assemblies. Herein, we show a real‐time fluorescence imaging method to probe the evolution of the interfacial dynamics of NP surfactants at the water/oil interface using aggregation‐induced emission (AIE) as a reporter for the transition of the assemblies into the jammed state. The AIEgens show typical fluorescence behavior at densities at which they can move and rotate. However, when aggregation of these fluorophores occurs, the smaller intermolecular separation distance arrests rotation, and a significant enhancement in the fluorescence intensity occurs.
Li‐Rich Li2[Ni0.8Co0.1Mn0.1]O2 for Anode‐Free Lithium Metal Batteries
Authors: Lin Liangdong , Qin Kun , Zhang Qinghua , Gu Lin , Suo Liumin , Hu Yong‐sheng , Li Hong , Huang Xuejie , Chen Liquan
Published: January 2021

Anode‐free lithium metal batteries can maximize the energy density at the cell level. However, without the Li compensation from the anode side, it faces much more challenging to achieve a long cycling life with a competitive energy density than Li metal‐based batteries. Here, we prolong the lifespan of an anode‐free Li metal battery by introducing Li‐rich Li2[Ni0.8Co0.1Mn0.1]O2 into the cathode as a Li‐ions extender. The Li2[Ni0.8Co0.1Mn0.1]O2 can release a large amount of Li‐ions during the first charging process to supplement the Li loss in the anode, then convert into NCM811, thus extending the lifespan of the battery without the introduction of inactive elements. By the benefit of Li‐rich cathode and high reversibility of Li metal on Cu foil, the anode‐free pouch cells enable to achieve 447 Wh kg−1 energy density and 84 % capacity retention after 100 cycles in the condition of limited electrolyte addition (E/C ratio of 2 g Ah−1).
Effect of nanodiamonds and multi‐walled carbon nanotubes in thermoset hybrid fillers system: Rheology, dynamic mechanical analysis, and thermal stability
Authors: Xian Yeming , Kang Zhixin , Liang Xianrong
Published: January 2021

Recently, the interfacial bonding between nanodiamonds (DNDs) and multi‐walled carbon nanotubes (MWCNTs) in epoxy‐based nanocomposites were found. In this work, effects of amino functionalization on MWCNTs and DNDs introduction on rheology, dynamic mechanical properties, and thermal stability of MWCNTs epoxy‐based nanocomposites are discussed. The results show that pristine MWCNTs increase the complex viscosity, lower the molecular weight of epoxy net chains as well as glass transition temperature (Tg), and expand the phase separation. Amino functionalization of MWCNTs make the behaviors above disappeared nearly. Besides, introduction DNDs improved Tg and restricted the phase separation as well, but the high complex viscosity and non‐Newtonian behavior remains. This work may provide inspirations for the further researches about hybrid fillers.