bluuebunny/crossref_metadata_2025 huggingface dataset:
Cooperation culture amongst knowledge workers: A case study of the IT sector in Poland
Authors: Pietruszka-Orty Anna
Published: August 2021

The knowledge workers who form the core of the crew of a modern organization have emerged. They have a unique position in an enterprise, which complicates the incentive system building process and managers' formal impact on their activities. With a "deep-smarts" status, they adopt the attitudes that restrain or even intentionally hide knowledge flow. Providing support to organizational culture is crucial for motivating knowledge workers to contribute to an organization with their knowledge. This research paper is mainly aimed at identifying knowledge workers' preferences for organizational culture. The paper focuses on indicating the directions of the development of Polish IT companies' organizational culture in line with the attitudes of the professionals aiming to stimulate their involvement in the implementation of specific knowledge diffusion sub-processes. The paper is based upon the empirical research conducted on a sample of 105 IT sector knowledge workers in Poland in 2020.
Financial engineering to optimize risk management in banks based on Interest Rate Swaps to better hedge the exposure to interest rate fluctuations the case of banks in Syria
Authors: Akhmedov Fakhraddin , Zeitoun Mhd , Al Humssi
Published: August 2021

The banking system is affected by uncertainties related to the evolution of pandemic. One of the identified risks is that of a fluctuation of rates. Volatility of Interest rates is one of the major risks for the banking system. Therefore, financial engineering can be used as a very important hedging practice for banks against such a risk. The aim of this study is to develop a risk hedging mechanism to better overcome market volatility by hedging position against the exposure to interest rate risk based on credit derivatives. Therefore, this study uses Interest Rate Swaps (IRS)s to better hedge the exposure of banks to interest rate fluctuations in stress conditions giving consideration to the case study of banks in Syria in optimizing hedging practices based on Interest Rate Swaps. The aim is to use financial engineering to provide banks with a hedging technique to better absorb shocks in times of stress conditions. This has been discussed and illustrated with visual model diagrams. The case study of banks in Syria is not just the story of individual banks but a window into how to hedge the exposure of banks in stress conditions. In the end, most banking crises are quite similar. The recommendations set out in this study provide banks with an optimized hedging practice which is not part of current financial engineering at banks in Syria.
Scientific review digitalization of corporate culture as a factor influencing ESG investment in the energy sector
Authors: Zainullin Sergei , Zainullina Olga
Published: August 2021

The popularity of ESG (Environmental, Social and Governance)-investing is growing rapidly all over the world. More and more investors are moving from the traditional investment paradigm to investing based on the principles of environmental social corporate responsibility. One of the most affected by this trend is the energy industry. The report discusses the possibilities of applying methods of digitalization of corporate culture to increase the attractiveness of enterprises in the energy industry for ESG investment. The study is based on the use of such methods of scientific knowledge as dialectical, a combination of historical and logical unity, structural analysis, traditional methods of economic analysis and synthesis, a review of both scientific sources describing ESG investment and the practical implementation of ESG approaches in the practice of corporations is carried out. The results are based on an analysis of current corporate policies and the implementation of ethical policies in corporate social reporting. The article provides an overview of theoretical studies in relation to corporate non-financial reporting and the principles of responsible investment, provides statistical data on the attitude of investors towards ESG investment, analyzes the best practices of energy companies in digitalization, improving corporate culture to make them more attractive for ESG investment.
Evolution of traditional banks' business models
Authors: Panova Galina
Published: August 2021

The article considers topical issues of how banks are developing in the new realities of the digital economy, and presents the results of research on theoretical and practical aspects of banks' business models evolution. The methodology uses such approaches as scientific abstraction, system and factor analysis, methods of grouping, detailing, and synthesis. The topic is relevant for banks first of all from the economic science point of view, since until now the conceptual apparatus of not only the types of bank business models but also the definition of bank business models and their ecosystems remain controversial. However, in practice the applying of new strategic solutions is needed to solve the triune task: to ensure profitability of banks' business while maintaining liquidity and minimizing risks. The obtained results allowed us to reveal the important role of the banks' business models innovative transformation, as well as to reveal the tendency of improving the intermediary function of banks on the modern stage of digital technologies' development. The article substantiates the need to develop new approaches to administering business processes, expanding banking activities using digital platforms, and reveals the problem that requires the speediest solutions in developing regulation standards for financial ecosystems.
The experience of applying mathematical methods for analysis of the microgeneration sector in Russia
Authors: Vladimirovich Gavriusev , Vasilyevich-Chernyaev Maxim
Published: August 2021

The paper relates to substantiation of reasonability of applying the mathematical methods to economic researches. The developed by the author algorithm for determining the relevant for Russia foreign experience of the microgeneration sector development on the basis of the Gaussian mixture model is provided as an example. This algorithm used to be successfully applied within the framework of a larger scale research related to the problems of development and increasing of the economic efficiency of the microgeneration sector in Russia. The paper provides for the mathematical description and economic feasibility study of the measures taken. High efficiency of using the quantitative methods for obtaining the results, which are significant from the point of view of the economic feasibility study, is underlined. There are also described the problematic issues of the suggested algorithm and possible ways of solving thereof. Finally, the conclusion is made about a high heuristic value of the above-described algorithm and the reasonability of applying the mathematical methods to economic researches.
Bri cooperation system: General framework and development path
Authors: Yongliang Lin
Published: August 2021

Since the Belt and Road Initiative was brought up in 2013, a wide variety of mechanisms and platforms under its framework have sprung up, which actively led the initiative to a deeper and more practical fashion. OECD, WEF and other mechanisms and platforms with long-accumulated experience can inspire the initiative in building its cooperation system. In order to promote the system, we need to highlight the leading, professional, practical, popularity and justice-based characteristics of those mechanisms and platforms, to connect with which advanced ideas and institutions should be integrated dynamically into the process.
The international economic system in the historical process and China's role
Authors: Wei Li
Published: August 2021

The history of the construction and development of the international economic system can be traced back to the establishment of the Bretton Woods system at the end of World War II. After more than 70 years, the international economic system in different economic fields such as trade, finance and investment, as well as at the global and regional levels, has been continuously built, reformed and evolved, forming a scene of variety of current international economic system. During this period, China`s role in the international economic system has also experienced gradual changes, and has generally undergone a transformation from a bystander to a part trying to fit in, then to a participant, and finally a leader. The evolution of China`s role is not only the cause of the institutional changes in the international economic system, but also the outcome. They are complementary and closely related to each other. In the development of the international economic system, China has gradually moved from the periphery to the center, which is both an opportunity and a challenge for China.
Diplomatic transformation and developing a new type of international relations: A perspective to observe and understand new China's diplomacy
Authors: Cungang Wang
Published: August 2021

Since 1949, diplomacy of the People's Republic of China has successively undergone transformation for three times, namely diplomacy of establishing the PRC, diplomacy of enriching the country and major-country diplomacy. Developing a new type of international relations is an effective way to achieve diplomatic transformation of New China, but its connotations vary with different periods of history. During the two turnarounds from 1949 to 2012, New China's diplomacy, which holds up the Principle of Independence and Five Principles of Peaceful Coexistence, took shape in the practice of developing a new type of international relations. The former principle have played an important role in safeguarding China's sovereignty and dignity, protecting national security and promoting the country's development. The latter became basic norm of international relations and basic principle of international law due to its openness and inclusiveness. Since the 18th CPC National Congress, in face of profound changes unseen in a century and a new posture for China to increasingly move toward the center of the world arena, President XI Jinping made great endeavors to promote major country diplomacy with Chinese characteristics, and actively touched upon building a new type of international relations featuring mutual respect, fairness, justice, and win-win cooperation, which innovates on and develops the Principle of Independence and Five Principles of Peaceful Coexistence, as well as pushes forward the world multi-polarization process and the building of a community with a shared future for mankind.
Preliminary Phytochemical Analysis of Aqueous Extract of Leaf Psidium guajava and Its Effect on Some Haematological Parameters
Authors: Uneze M. I. , Azionu D. N.
Published: August 2021

Various parts of psidium guajava linn are used in ethnomedicine in controls and treatments of different disorders such as liver, heart, and blood related disorders [11]. This research work investigate qualitative phytochemical composition of ethanol leaf extract of psidium guajava linn and its effect on some hematological parameters in albino rats. Qualitative phytochemical analysis of the extract was performed by standard procedures. A total of 20 adult male albino rats were used, they were randomly placed into 5 groups (A, B, C, D and E) each group containing 4 rats groups A, B, C, and D were administered, via oral intubation, the extract at doses of 200, 400, 600, and 800 mg/kg body weight respectively of the extract for 7 consecutive days. Phytochemical screening shows that the extract was rich in tannins anthraquinones, and flavonoid while alkaloids, saponins, terpenes and glycoside were slightly present. There was a decrease in the average body weight, physical activities, and feed and water intake of the rats in the test groups relative to the control hemoglobin concentrate, total white blood cell and packed cell volume recorded in the groups  administered the extract were significantly (p<0.05) higher than in the control this effect on  the haemotological parameters was found to be dose dependent. The findings of this study suggest that the aqueous extract of the fruit plants may be useful in control and treatment of blood related disorders.  These useful applications may be as a result of the phytochemical present in the extract.
Some Heavy Metals Correlated Negatively with Total Antioxidant Capacity, Glutathione Peroxidase, Fructose, and Testosterone in Seminal Plasma of Oligospermic and Azoospermic Males
Authors: Umoinyang Edidiong Peter , Elekima Ibioku , Onwuli Donatus
Published: August 2021

Aim: The study aimed to investigate the relationship between some heavy metals and total antioxidant capacities, glutathione levels, fructose, and testosterone in seminal plasma of infertile azoospermic and oligospermic males in Akwa Ibom State of Nigeria.

Study Design:  A cross-sectional design with a total of 124 males included in the study of which 32 were azoospermic, 38, oligospermic, and 54, normospermic.

Place and Duration of Study: Semen samples were collected from the urology or fertility clinic of UUTH, St. Luke’s Hospital, Anua, and Ibom specialist hospital of Akwa Ibom State. However, laboratory assays were performed at the Department of Medical Laboratory Science, Rivers State University, Port Harcourt between May, 2018 and January, 2021.

Methodology: Semen specimens were collected after 3-5 days abstinence according to WHO criteria while seminal plasma were obtained from semen by spinning at 4500 rpm for 10 minutes and stored at -700C prior to laboratory analysis. Atomic absorption spectrometer (AAS) was used to determine the levels of heavy metals while ELISA methods were used to determine testosterone and GSH concentrations. TAC and fructose assays were carried out using spectrophotometric methods.

Results: Results showed that non-essential heavy metals such as lead, mercury, and arsenic correlated negatively with testosterone, fructose, and antioxidant activities of the seminal plasma in azoospermic subjects. In addition, lead and mercury correlated positively in the azoospermic subjects. Meanwhile, selenium, an essential heavy metal, correlated positively with testosterone and antioxidant activities in oligospermic subjects with 11-19 x106cells/ml.

Conclusion: The levels of non-essential heavy metals in azoospermic subjects precipitated poor anti-oxidant and testosterone activities inducing oxidative stress while in oligospermic subjects, selenium and antioxidant parameters and testosterone were in good association indicating improved antioxidant activities and testicular function.
Bibliometric Analysis of Publications from Pubmed on Non Communicable Disease and Ayushman Bharat Health and Wellness Center
Authors: Ambekar Shrikant Madhukar , Quazi S. Z. , Gaidhane Abhay , Patil Manoj , Umate Roshan
Published: August 2021

Background: Increase in Non-communicable diseases in spite of many steps taken for prevention and control is challenge for all over world, these epidemiological transition leas to need of health care services at community level with quality health care services. Under Ayushman Bharat Programme transformation of existing health facilities in Health and Wellness center to deliver universal and free comprehensive primary health care. Delivering Non communicable disease health services is one of major component of HWCs.

Objectives:.Study was conducted to conduct analysis of Publication on Non communicable disease and Ayushman Bharat Health and Wellness Center.

Methodology: Retrospective observational study was conducted On 30.01.2021, the Pubmed was accessed to collect publication on Non communicable disease and Ayushman Bharat, Health and Wellness Centre. Bibliometric analysis was conducted with quantity indicators for measuring productivity and quality indicators for measurement of output. Structural indicator for measured inter linkage between authors, publication Information on PubMed was used for analysis with the help of R Studio.

Results: The PubMed search filtered for annual scientific production including journal ,book , document etc from 1978 to 2021 are found total publication are 2377.Out of Total publication after analysing most relevant sources include PLOS One was found most relevant source around 91.In Correspondence Authors from various countries India is on 3rd number which is around 114 authors.

Conclusion: There are many publications on this key words and most publication are published in recent 10 years. Indian contribution in this area in on 3rd no in all over world.
Prevalence of Lung Dysfunction in Type II Diabetes Mellitus
Authors: Karuppan V. Ashwin
Published: August 2021

The pulmonary function test was also used in this study as a screening tool to detect Lung Dysfunction in asymptomatic Type 2 diabetic patients. This is a cross-sectional study conducted in a hospital. This study involved 100 patients, including 41 males and 59 females ranging in age from 23 to 75 years old, who underwent spirometry after providing their consent for the study. FEV1 and FVC absolute values were compared to predicted values and represented as a percentage of predicted values. The current study's data were analysed with SPSS 15.0, and the results are reported in Descriptive Statistics such as Frequency, Percentage, Range, Mean, Standard Error (Mean), and 95 percent Confidence Interval. The current findings demonstrated that the prevalence of Lung Dysfunction was 63 (64.9%) when the duration of diabetes was less than 5 years, compared to 23 (23.7%) when the length was more than 5 years. With a Chi Square value of 3.85 (P=0.05), this revealed a statistically significant difference.
RP-HPLC Method Development and Validation for Determination of Tigecycline in Bulk and Pharmaceutical Dosage form
Authors: Bhavyasri K. , Mounika C. H. , Vallakeerthi Narmada , Sumakanth M.
Published: August 2021

Aims: To develop and validate a new, simple, rapid, precise and accurate Reverse Phase High Performance Liquid Chromatographic (RP-HPLC) method for the quantitative determination of Tigecycline in bulk and pharmaceutical dosage form.

Study Design:

Place and Duration of the Study: RBVRR women's college of pharmacy, Barkatpura, Hyderabad, between june 2019 and july 2020.

Methodology: The RP-HPLC method was developed on Sunsil C18 150 mm x 4.6mm x 5µ column using acetonitrile : water (pH maintained at 3.5 with acetic acid) [70:30] as mobile phase at flow rate 0.8 ml/min and UV detection at 250 nm.

Results: Tigecycline exhibited linearity over the concentration range of 5-40 µg/mL (R2 > 0.999). The analytical method showed good precision with % RSD below 2. The method showed suitable accuracy and robustness.

Conclusion: Validation of the developed method was done as per International Conference on Harmonization (ICH) Q2R1 guidelines.
Pilot Study to Test Efficacy of Sira Vedha in Non-Alcoholic Fatty Liver Disease
Authors: Sawarkar Gaurav , Sawarkar Punam , Desai Priti , Tiwari Madhulika
Published: August 2021

Introduction: Sushruta said that the Sira Vedha (phlebotomy) at Dakshin Kurpara Sandhi (Right Elbow Joint) as a therapy for Yakrit Vikara (Liver Diseases). Modern science also on the same page that phlebotomy treatment for some liver diseases but did not mention the exact site for phlebotomy. Similarly, there is variation in the withdrawal of blood and time duration, every research study indicating different quantity to be withdrawn and the interval between two sessions. In the context of Ayurveda, both the things mentioned earlier are mentioned well in advance. Still, because of a lack of clinical evidence, one cannot confidently practice it in routine exercise. Thus, there is a need to validate Sushruta's principle with clinical evidence for liver diseases.

Methodology: Twenty eligible patients who had Non-Alcoholic Fatty Liver Disease (NAFLD) Grade I/II were enrolled in the pilot study and randomly allotted for control (group A) and trial group (group B). Obtained written informed consent, each patient's blood serum was taken for aspartate transaminase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALK-P), and lipid profile. Then, group A patients were advised only diet alterations. Group B patients underwent diet alteration and Sira Vedha (phlebotomy) with 65 cc blood three times by the interval of 15 days. Before every phlebotomy, checked hemoglobin for safety purposes to discontinued the patient. The blood sample was taken before recruitment in the study and after the last follow-up, i.e., the 60th.

Day—observation & Results: Compared the serum values of the first and final follow-up. Twenty patients (12 males and eight females) were enrolled, and the mean average age was 34.8 ± 7.84 years. This pilot study suggested that there was the improvement in liver enzymes and lipid profile significantly (P < 0.050) in group B compared to group A. Still, the changes that occurred with the treatment are not good enough to exclude the possibility that the difference was due to chance or because of small sample size. So, we can conclude that phlebotomy can improve liver enzymes and lipid profiles in patients with NAFLD.
Farm Machine and Female Labour Participation A Study of Indian Districts
Authors: Ahmad Syed Noman , Murtaza Mohd
Published: August 2021

Indian labour market has been witnessing a paradoxical situation in recent years. Despite registering higher economic development the female participation in economic activities has shown deceleration. The researchers in this field have identified several determinants and explanations at aggregate level. The present study is one of the few attempts to examine the trend of female participation in agriculture at district level. Taking number of tractor in a district as a proxy for farm machination, the study confirms an inverse relationship between farm machines and female participation in agriculture. It resolves the paradox in terms of lower women participation in agriculture sector.
Analysis of India's Rural Development Budgetary Implementations
Authors: Azeez N.P. Abdul
Published: August 2021

Government expenditure patterns have changed tremendously over the last few years, especially in developing countries like India. Many studies found a positive relationship between government spending and rural development and poverty reduction and thereby economic growth. For a country like India, whose proportion of the rural population is about 70 per cent, governments' efforts in the form of its expenditure toward rural development are vital. It is also essential to analyze the relative contribution of various expenditures to rural development and reduce the poverty of rural people. The purpose of this paper is to review and analyze the head-wise budgetary and actual expenditure on the various centrally sponsored scheme for rural development of India.
Short Commercialization Circuits in Local Supply Chains: Economic Revival in the Pandemic
Authors: Rodríguez Dustin Tahisin Gómez , Laverde Marìa Yolanda , Pérez Ehyder Mario Barbosa
Published: August 2021

The general objective of this article is to describe the strategy called Short Commercialization Circuits SCC as a way of supplying local chains in 2020 by the Unidad Administrativa Especial de Organizaciones Solidarias (UAEOS) in Colombia to counteract the negative impacts of the COVID19 pandemic and to improve the social fabric and the ecosystem of the beneficiary territories. The methodology is qualitative, and its methods are documentary review. The main conclusion is that Short Commercialization Circuits such as Public Procurement are strategies that can improve the quality of life of farmers in their territory.
The Establishment of an Optimal Protocol for Contrast-Enhanced Micro-Computed Tomography in the Cloudy Catshark Scyliorhinus torazame
Authors: Ito Takaomi , Furuya Masaru , Sasai Kazumi
Published: August 2021

The purpose of this study was to determine the optimal imaging protocol for contrast-enhanced computed tomography (CECT) using micro-CT (μ-CT) for the posterior cardinal vein (PCV), dorsal aorta (DA), hepatic portal vein (HPV), kidney, liver, cephalic arteries (CAs), and gills of Cloudy Catsharks Scyliorhinus torazame. Additionally, we examined the availability of CECT screening for the coelomic organs. Different doses of iopamidol (100, 300, 500, and 700 mg iodine [mgI]/kg) were administered intravenously for 20 s in six sharks. The CT scans from the pectoral girdle to the pelvic girdle were performed at 0–600 s after administration. Contrast-enhanced CT imaging of the CAs, gills, and coelomic organs was examined. Assessment of the signal enhancement value revealed that the PCV was easily visualized with all contrast doses at 25 s. The CAs, gills, and DA were visible at a slightly higher dose (CAs and gills: 200 mgI/kg at 40 s; DA: 300 mgI/kg at 50 s). The HPV was obvious at a dose of at least 500 mgI/kg after a 150-s delay. The parenchyma of the kidney had a contrast effect at 300 mgI/kg, 150 s after the contrast effect of the renal portal system disappeared. The liver, which stores a lot of lipids, had poor overall contrast enhancement that was optimized at the highest dose of 700 mgI/kg. Contrast-enhanced CT screening at 700 mgI/kg and 150 s is likely to obtain the optimal imaging of the reproductive organs, such as the ovary, oviducal gland, uterus, and testis. The present findings can be applied not only to clinical practice but also to academic research and education on elasmobranchs in aquariums.
Development and Validation of a Juvenile Spondyloarthritis Disease Flare Measure: Ascertaining Flare in Patients With Inactive Disease
Authors: Weiss Pamela F. , Brandon Timothy G. , Ryan Meghan E. , Treemarcki Erin B. , Armendariz Stephanie , Wright Tracey B. , Godiwala Chetna , Stoll Matthew L. , Xiao Rui , Lovell Daniel
Published: August 2021

Objective

Our objective was to develop and validate a composite disease flare definition for juvenile spondyloarthritis (SpA) that would closely approximate the clinical decision made to reinitiate or not reinitiate systemic therapy after therapy de‐escalation.

Methods

Retrospective chart reviews of children with SpA who underwent systemic therapy de‐escalation of biologic or conventional disease‐modifying antirheumatic drugs were used to develop and validate the flare outcome. Data on independent cohorts for development (1 center) and validation (4 centers) were collected from large tertiary health care systems. Core measure thresholds and candidate disease flare outcomes were assessed using sensitivity, specificity, positive predictive values (PPVs) and negative predictive values (NPVs), and the receiver operating characteristic (ROC) area under the curve (AUC), with physician assessment of active disease plus re‐initiation of standard dose of systemic therapy as the reference standard.

Results

Of the candidate definitions, clinically meaningful worsening in ≥3 of the following 5 core measures performed best: caregiver/patient assessment of well‐being; physician assessment of disease activity; caregiver/patient assessment of pain, physical function, and active joint count. The ROC AUC was 0.91, PPV 87.5%, NPV 98.1%, sensitivity 82.4%, and specificity 98.7%. Cronbach's α was 0.81, signifying internal consistency, and factor analysis demonstrated that the outcome measured 1 construct. The Juvenile SpA Flare measure had face validity according to 21 surveyed pediatric rheumatologists. Juvenile SpA Flare had an ROC AUC of 0.85, a PPV of 92.3%, and an NPV of 96.8% in the validation cohort.

Conclusion

There is initial support for the validity of the Juvenile SpA Flare measure as a tool to identify disease flare in juvenile SpA patients de‐escalating therapy, and the measure is potentially applicable in clinical practice, observational studies, and therapeutic trials.
Identifying Content Themes in Primary Care Physician and Rheumatologist Communications Within Electronic Consultations: A Qualitative Study
Authors: Lee Jeanie , Rikin Sharon , Jain Ruchi
Published: August 2021

Objective

Electronic consultation (eConsult) communications between primary care physicians (PCPs) and rheumatologists may reveal common knowledge gaps and educational opportunities. The aim of our study was to identify content themes in PCP questions and rheumatology recommendations through analysis of eConsult and the need for rheumatology appointments and facilitated urgent visits post‐eConsult.

Methods

A descriptive cross‐sectional study involving qualitative and quantitative analysis of rheumatology eConsults in a single center was performed from May 1, 2019, to January 9, 2020. Conventional content analysis was used to derive content themes in PCP questions and rheumatology recommendations. We evaluated the proportion of eConsults, which included a need for rheumatology appointments and expedited visits through frequency counts.

Results

Among 120 rheumatology eConsults, six PCP questions and five rheumatology recommendation content themes were identified. The most common PCP question themes were the following: 1) joint pain, 2) suspected rheumatic disease differential, and 3) abnormal laboratory tests. The most common rheumatology recommendation or teaching themes were the following: 1) education on differential diagnoses of rheumatic diseases, 2) education on the specific rheumatic disease, and 3) laboratory test interpretation. The majority of eConsults (82%) recommended a subsequent rheumatology appointment, and 27% facilitated an expedited appointment.

Conclusion

In this analysis of eConsults, we identified common knowledge gaps in PCPs and rheumatology educational topics, including differentiating inflammatory from noninflammatory arthritis, using caution in interpreting abnormal laboratory tests without clinical manifestations, managing chronic gout, evaluating elevated creatine phosphokinase levels, and differentiating C‐reactive protein (CRP) from high‐sensitivity CRP. Timely feedback through eConsult recommendations may allow for focused educational opportunities.
Dopant Engineering for Spiro‐OMeTAD Hole‐Transporting Materials towards Efficient Perovskite Solar Cells
Authors: Seo Ji‐Youn , Akin Seckin , Zalibera Michal , Preciado Marco A. Ruiz , Kim Hui‐Seon , Zakeeruddin Shaik M. , Milić Jovana V. , Grätzel Michael
Published: August 2021

One of the most prominent hole‐transporting material (HTM) for hybrid perovskite solar cells has been 2,2″,7,7″‐tetrakis[N,N‐di(4‐methoxyphenyl)amino]‐9,9′‐spirobifluorene (spiro‐OMeTAD), which is commonly doped with metal bis(trifluoromethylsulfonyl)imide (M(TFSI)n) salts that contribute to generating the active radical cation HTM species. The underlying role of the metal cation, however, remains elusive. Here, the effect of metal cations (M = Li, Zn, Ca, Cu, and Sc) on doping spiro‐OMeTAD is analyzed by a combination of techniques, including electron paramagnetic resonance spectroscopy and cyclic voltammetry, which is complemented by photovoltaic device and hole mobility analysis. As a result, the authors reveal the superiority of Zn(TFSI)2 salts in device performances as compared to the others, including redox‐active Cu(TFSI)2. This analysis thereby unravels new design principles for dopant engineering in HTMs for hybrid perovskite photovoltaics.
Amino Acid‐Induced Interface Charge Engineering Enables Highly Reversible Zn Anode
Authors: Lu Haotian , Zhang Xuanlin , Luo Minghe , Cao Keshuang , Lu Yunhao , Xu Ben Bin , Pan Hongge , Tao Kai , Jiang Yinzhu
Published: August 2021

Despite the impressive merits of low‐cost and high‐safety electrochemical energy storage for aqueous zinc ion batteries, researchers have long struggled against the unresolved issues of dendrite growth and the side reactions of zinc metal anodes. Herein, a new strategy of zinc‐electrolyte interface charge engineering induced by amino acid additives is demonstrated for highly reversible zinc plating/stripping. Through electrostatic preferential absorption of positively charged arginine molecules on the surface of the zinc metal anode, a self‐adaptive zinc‐electrolyte interface is established for the inhibition of water adsorption/hydrogen evolution and the guidance of uniform zinc deposition. Consequently, an ultra‐long stable cycling up to 2200 h at a high current density of 5 mA cm−2 is achieved under an areal capacity of 4 mAh cm−2. Even cycled at an ultra‐high current density of 10 mA cm−2, 900 h‐long stable cycling is still demonstrated, demonstrating the reliable self‐adaptive feature of the zinc‐electrolyte interface. This work provides a new perspective of interface charge engineering in realizing highly reversible bulk zinc anode that can prompt its practical application in aqueous rechargeable zinc batteries.
Recent Developments of Microenvironment Engineering of Single‐Atom Catalysts for Oxygen Reduction toward Desired Activity and Selectivity
Authors: Li Longbin , Huang Bingyu , Tang Xiannong , Hong Yaoshuai , Zhai Weijuan , Hu Ting , Yuan Kai , Chen Yiwang
Published: August 2021

Oxygen reduction reaction (ORR) is an essential process for sustainable energy supply and sufficient chemical production in modern society. Single‐atom catalysts (SACs) exhibit great potential on maximum atomic efficiency, high ORR activity, and stability, making them attractive candidates for pursuing next‐generation catalysts. Despite substantial efforts being made on building diversiform single‐atom active sites (SAASs), the performance of the obtained catalysts is still unsatisfactory. Fortunately, microenvironment regulation of SACs provides opportunities to improve activity and selectivity for ORR. In this review, first, ORR mechanism pathways on N‐coordinated SAAS, electrochemical evaluation, and characterization of SAAS are displayed. In addition, recent developments in tuning microenvironment of SACs are systematically summarized, especially, strategies for microenvironment modulation are introduced in detail for boosting the intrinsic 4e−/2e− ORR activity and selectivity. Theoretical calculations and cutting‐edge characterization techniques are united and discussed for fundamental understanding of the synthesis–construction–performance correlations. Furthermore, the techniques for building SAAS and tuning their microenvironment are comprehensively overviewed to acquire outstanding SACs. Lastly, by proposing perspectives for the remaining challenges of SACs and infant microenvironment engineering, the future directions of ORR SACs and other analogous procedures are pointed out.
Wearable Optical Sensing of Strain and Humidity: A Patterned Dual‐Responsive Semi‐Interpenetrating Network of a Cholesteric Main‐Chain Polymer and a Poly(ampholyte)
Authors: Shi Xiuyi , Deng Zixuan , Zhang Pei , Wang Yao , Zhou Guofu , de Haan Laurens T.
Published: August 2021

Main‐chain cholesteric liquid crystal polymers are a promising candidate for the development of responsive photonic devices due to the combination of selective reflection and soft, elastic properties, but it is difficult to enhance these materials with new kinds of responsiveness due to the inherent lack of mesogenic side groups. Here, a new strategy is showed to obtain a dual‐responsive elastic cholesteric polymer material by preparing a semi‐interpenetrating network consisting of a cholesteric main‐chain polymer and a hygroscopic poly(ampholyte). The material is shown to undergo a redshift of the reflected color upon swelling with water, while the color blueshifts when a strain is applied. Color patterns can be prepared by localized photopolymerization at different temperatures, leading to brightly colored responsive images with high contrast. Due to the elastic nature of the material, it can easily be made into a wearable device, and its application as a multifunctional smart sensor for sweat detection and movement detection is demonstrated. The results show that new responsiveness can be added to main‐chain cholesteric polymers by preparation of interpenetrating networks, which can be further extended to develop various kinds of multi‐responsive smart materials.
A Competitive Reaction Strategy toward Binary Metal Sulfides for Tailoring Electromagnetic Wave Absorption
Authors: Liu Jiaolong , Zhang Limin , Zang Duyang , Wu Hongjing
Published: August 2021

The development of multicomponent dielectric composites has become a mainstream approach for obtaining excellent electromagnetic wave (EMW) absorbers. However, conventional component introduction is often performed blindly and based only on semiempirical rules, lacking precise modulation of components, interfaces, and defects during the reaction process. Herein, a competitive reaction mechanism is proposed for the first time, in which not only the metal ion concentration but also its characteristic are two feasible parameters to control the components, interfaces, and defects to tailor the EMW absorption performances of Cu‐based binary metal sulfides. The appropriate heterogeneous interfaces and components and the abundant defects can synergistically benefit the EMW absorption capacity by forming perfect impedance matching and multiple dielectric polarizations. As a result, combined with these advantages, an effective absorption band) of 6.80 GHz (6.3–13.1 GHz) is achieved at 2.80 mm for Cu–Co binary metal sulfide, showing the sole middle‐frequency broadband absorption of reported sulfide‐based absorbers to date. Other Cu‐based binary metal sulfides deliver different EMW absorption behaviors. This work breaks through the limitation of traditional component design, opening up a novel methodology for designing multicomponent composites beyond sulfides with broadband absorption.
Photodoping and Fast Charge Extraction in Ionic Carbon Nitride Photoanodes
Authors: Adler Christiane , Selim Shababa , Krivtsov Igor , Li Chunyu , Mitoraj Dariusz , Dietzek Benjamin , Durrant James R. , Beranek Radim
Published: August 2021

Ionic carbon nitrides based on poly(heptazine imides) (PHI) represent a vigorously studied class of materials with possible applications in photocatalysis and energy storage. Herein, for the first time, the photogenerated charge dynamics in highly stable and binder‐free PHI photoanodes using in operando transient photocurrents and spectroelectrochemical photoinduced absorption measurements is studied. It is discovered that light‐induced accumulation of long‐lived trapped electrons within the PHI film leads to effective photodoping of the PHI film, resulting in a significant improvement of photocurrent response due to more efficient electron transport. While photodoping is previously reported for various semiconductors, it has not been shown before for carbon nitride materials. Furthermore, it is found that the extraction kinetics of untrapped electrons are remarkably fast in these PHI photoanodes, with electron extraction times (ms) comparable to those measured for commonly employed metal oxide semiconductors. These results shed light on the excellent performance of PHI photoanodes in alcohol photoreforming, including very negative photocurrent onset, outstanding fill factor, and the possibility to operate under zero‐bias conditions. More generally, the here reported photodoping effect and fast electron extraction in PHI photoanodes establish a strong rationale for the use of PHI films in various applications, such as bias‐free photoelectrochemistry or photobatteries.
Highly Conductive Amorphous Pentlandite Anchored with Ultrafine Platinum Nanoparticles for Efficient pH‐Universal Hydrogen Evolution Reaction
Authors: Zhang Chenxu , Cui Yanan , Yang Yilin , Lu Linguo , Yu Shansheng , Meng Zeshuo , Wu Yixian , Li Yaxin , Wang Yanan , Tian Hongwei , Zheng Weitao
Published: August 2021

The devise and fabrication of highly efficient electrocatalysts have momentous practical significance for the development of future hydrogen energy systems. However, their potential uses in support construction are not well studied. In this work, a highly efficient electrocatalyst is developed for the hydrogen evolution reaction by anchoring single Pt atoms and clusters into functional amorphous pentlandite Fe5Ni4S8 (or FNS) to yield Pt–FNS composites. Amorphous FNS still provides great conductivity to the composites, thereby promoting rapid charge transfer. The presence of abundant defects in Pt–FNS composite catalysts induces pleasant atomic dispersion and anchoring of Pt species. In addition, the formation of single Pt atoms combined with clusters and low‐Pt‐loading improves the utilization of Pt and reduces the cost. The turnover frequency analysis suggests Pt–FNS systems possess significant unit catalytic activity. The synergetic catalytic effect issued from high conductivity, abundant active sites and elevated intrinsic activity forms Pt–FNS systems with efficient pH‐universal catalytic activity. The systems exhibit low overpotentials of only 30, 65, and 98 mV at 10 mA cm−2 under acidic, alkaline, and neutral conditions, respectively. In sum, the proposed route looks promising for the fabrication of new electrocatalysts with improved properties.
Designing Squaraine Dyes with Bright Deep‐Red Aggregation‐Induced Emission for Specific and Ratiometric Fluorescent Detection of Hypochlorite
Authors: Qiao Weiguo , Ma Teng , Wang Shuangshuang , Li Longjie , Liu Miao , Jiang Hao , Wu Yuzhou , Zhu Jintao , Li Zhong'an
Published: August 2021

Development of ratiometric fluorescent hypochlorite probes with strong long wavelength fluorescence in aqueous medium, high resistance to photobleaching, high sensitivity and selectivity, and low biological toxicity remains a challenge. In this work, a molecular design strategy is proposed that can transform the traditional squaraine dyes (SQs) with aggregation‐caused quenching character into aggregation‐induced emission (AIE)‐active luminogens by functionalizing the end‐groups with tetraphenylethylene units and further introducing hydrophilic sulfonate group as the side chains. The resulting TPE‐SQ5 not only emits strong deep‐red fluorescence with a high quantum yield of 11.0% and high photostability, but more encouragingly can serve as a ratiometric fluorescent hypochlorite probe with high selectivity and sensitivity (detection limit: 5.6 nm), which indeed is the first report for SQs. The detailed sensing mechanism study demonstrates that the oxindole product with sulfonate substitution is responsible for the ratiometric fluorescent response. Furthermore, TPE‐SQ5 nanoparticles with high biocompatibility and low cytotoxicity are successfully used for ratiometrically imaging exogenous and endogenous hypochlorite in living cells.
Facile Fabrication of Robust Hydrogen Evolution Electrodes under High Current Densities via Pt@Cu Interactions
Authors: Tan Yeshu , Xie Ruikuan , Zhao Siyu , Lu Xuekun , Liu Longxiang , Zhao Fangjia , Li Chunzhong , Jiang Hao , Chai Guoliang , Brett Dan J. L. , Shearing Paul R. , He Guanjie , Parkin Ivan P.
Published: August 2021

Durable and efficient hydrogen evolution reaction (HER) electrocatalysts that can satisfy industrial requirements need to be developed. Platinum (Pt)‐based catalysts represent the benchmark performance but are less studied for HER under high current densities in neutral electrolytes due to their high cost, poor stability, and extra water dissociation step. Here a facile and low‐temperature synthesis for constructing “blackberry‐shaped” Pt nanocrystals on copper (Cu) foams with low loading as self‐standing electrodes for HER in neutral media is proposed. Optimized hydrogen adsorption free energy and robust interaction induced by charge density exchange between Pt and Cu ensure the efficient and robust HER, especially under high current densities, which are demonstrated from both experimental and theoretical approaches. The electrode exhibits small overpotentials of 35 and 438 mV to reach current densities of ‐10 and ‐1000 mA cm−2, respectively. Meanwhile the electrode illustrates outstanding stability during chronoamperometry measurement under high current densities (‐100 to ‐400 mA cm−2) and 1000 cycles linear sweep voltammetry tests reaching ‐1000 mA cm−2. This study provides new design strategies for self‐standing electrocatalysts by fabricating robust metal–metal interactions between active materials and current collectors, thus facilitating the stable function of electrodes for HER under technologically relevant high current densities.
Retina‐Inspired Structurally Tunable Synaptic Perovskite Nanocones
Authors: Lee Kyuho , Han Hyowon , Kim Youngwoo , Park Jumi , Jang Seonghoon , Lee Hyeokjung , Lee Seung Won , Kim HoYeon , Kim Yeeun , Kim Taebin , Kim Dongho , Wang Gunuk , Park Cheolmin
Published: August 2021

Artificial photonic synapses with morphologically controlled photoreception, allowing for area‐dependent tunable light reception as well as information storage and learning, have potential for application in emerging photo‐interactive neuro‐computing technologies. Herein, an artificially intelligent (AI) photonic synapse with area‐density‐tunable perovskite nano‐cone arrays templated in a self‐assembled block copolymer (BCP) is presented, which is based on a field effect transistor with a floating gate of photoreceptive perovskite crystal arrays preferentially synthesized in a micro‐phase‐segregated BCP film. These arrays are capable of electric charge (de)trapping and photo‐excited charge generation, and they exhibit versatile synaptic functions of the nervous system, including paired‐pulse facilitation and long‐term potentiation, with excellent reliability. The area‐density variable perovskite floating gate developed by off‐centered spin coating process allows for emulating the human retina with a position‐dependent spatial distribution of cones. 60 × 12 arrays of the developed synapse devices exhibit position‐dependent dual functions of receptor and synapse. They are AI and exhibit a pattern recognition accuracy up to ≈90% when examined using the Modified National Institute of Standards and Technology handwritten digit pattern recognition test.
Ultrafast Responsive and Low‐Energy‐Consumption Poly(3‐hexylthiophene)/Perovskite Quantum Dots Composite Film‐Based Photonic Synapse
Authors: Chen Jung‐Yao , Yang Dong‐Lin , Jhuang Fu‐Cheng , Fang Yu‐Han , Benas Jean‐Sebastien , Liang Fang‐Cheng , Kuo Chi‐Ching
Published: August 2021

Emulation of photonic synapses through photo‐recordable devices has aroused tremendous discussion owing to the low energy consumption, high parallel, and fault‐tolerance in artificial neuromorphic networks. Nonvolatile flash‐type photomemory with short photo‐programming time, long‐term storage, and linear plasticity becomes the most promising candidate. Nevertheless, the systematic studies of mechanism behind the charge transfer process in photomemory are limited. Herein, the physical properties of APbBr3 perovskite quantum dots (PQDs) on the photoresponsive characteristics of derived poly(3‐hexylthiophene‐2,5‐diyl) (P3HT)/PQDs‐based photomemory through facile A‐site substitution approach are explored. Benefitting from the lowest valance band maximum and longest exciton lifetime of FAPbBr3 quantum dot (FA‐QDs), P3HT/FA‐QDs‐derived photomemory not only exhibits shortest photoresponsive characteristic time compared to FA0.5Cs0.5PbBr3 quantum dots (Mix‐QDs) and CsPbBr3 quantum dots (Cs‐QDs) but also displays excellent ON/OFF current ratio of 2.2 upon an extremely short illumination duration of 1 ms. Moreover, the device not only achieves linear plasticity of synapses by optical potentiation and electric depression, but also successfully emulates the features of photon synaptic such as pair‐pulse facilitation, long‐term plasticity, and multiple spike‐dependent plasticity and exhibits extremely low energy consumption of 3 × 10−17 J per synaptic event.