bluuebunny/crossref_metadata_2025 huggingface dataset:
When Oxygen Can Be Toxic? A Mini Review
Authors: Elshafei Ali Mohamed
Published: August 2020

No one within the past later a long time had in intellect that the oxygen we breathe that contributes to sparing the lives of millions of patients and the most component of life has no harmful impacts on the body. Oxygen and water are the soul of living beings in common but beneath certain    conditions such as weak immune status and lack of the body's ability to excrete natural   antioxidants happens that the oxygen atom responds as a receptor for electrons, since its structure within the case of electronic soundness has two electrons that are not bound and as a result of progressive responses that create a few intermediate compounds. (Such as hydroxyl radical    (•OH), hydrogen peroxide (H2O2) and superoxide anion (•O-2) that are hurtful to human’ organs     and influence the extraordinary degree of cell division process and the physiological activities       that it performs since it could be a capable oxidizer. These reactive atoms and free radicals    inferred from atomic oxygen are called Reactive Oxygen Species (ROS). In spite of the fact that ROS play a key part as a flag-bearer in ordinary cell flag transduction and cell cycling, they have long been known to be a component of the immune reaction of safe cells to microbial invasion. ROS are created as byproducts during the mitochondrial electron transport of aerobic respiration or by oxido/reductase proteins and metal-catalyzed oxidation. The primary step in ROS generation is the reduction of atomic oxygen (O2) to anion superoxide (•O-2), is the antecedent of other responsive species. For this reason, the significance of normal cancer prevention agents has gotten to be vital to urge freed of the poisonous quality of ROS and particular antioxidant supplement ought to be given to improve the diet. Among the well-known antioxidants and cancer prevention agents are glutathione, vitamins C and D as well as enzymes such as, superoxide dismutase, catalase and peroxidase which contribute successfully to the disposal of these oxidizing substances.
The effects of Corporate Governance, Audit Quality, and Conservatism on Loan Collateral Requirements
Authors: Butar Butar Sansaloni
Published: August 2020

In competitive credit markets, borrowers and lenders have equal information on default risks. Under these circumstances, loan collateral are less important in credit decision-making. But in emerging credit market,  like Indonesia, borrowers and lenders do not possess equal information on firms’ future prospect, making use of collateral in mitigating default risk have become common practice. Despite strong theoretical support for the use of collateral to protect lenders from default risk, excessive protection may have a negative effect on the debt markets. However,  some Indonesian firms are not required to provide collateral for bank debts. This study examines the effect of Board of Commissioners independence, governance committees, audit quality, and conservatism on the likelihood of using loan collateral. Using slovin formula, as much as 785 firm listed in Indonesia Stock Exchange were collected during sample period of 2012-2015.  Logistic regression analysis suggest that firms with higher Board of Commissioners independence, having separate governance committee, hire Big 4 auditors, apply conservative accounting policies are less likely to provide loan collateral.
PENGARUH PERCEIVED USEFULNESS, PERCEIVED EASE OF USE, TRUST, DAN SECURITY TERHADAP MINAT PENGGUNAAN GOPAY PADA GENERASI X DI SURABAYA
Authors: Kumala Debby Cynthia , Pranata Joshua Wilson , Thio Sienny
Published: August 2020

Penelitian ini dilakukan untuk mengetahui apakah dimensi perceived usefulness, perceived ease of use, trust, dan security memiliki pengaruh signifikan terhadap minat penggunaan GoPay pada generasi X Surabaya. Penelitian ini menggunakan penelitian kuantitatif dengan menyebarkan kuesioner kepada 100 orang responden. Hasil penelitian menunjukkan bahwa dimensi perceived usefulness, perceived ease of use, trust, dan security secara simultan berpengaruh positif dan signifikan terhadap minat penggunaan aplikasi GoPay untuk pembelian makanan dan minuman pada generasi X Surabaya. Dari empat dimensi tersebut, perceived ease of use menjadi faktor yang paling dominan dalam mempengaruhi minat generasi X untuk menggunakan aplikasi GoPay untuk bertransaksi makanan dan minuman
Statistical Learning for Predicting Dengue Fever Rate in Surabaya
Authors: Halim Siana , Felecia Felecia , Octavia Tanti
Published: August 2020

Dengue fever happening most in tropical countries and considered as the fastest spreading mosquito-borne disease which is endemic and estimated to have 96 million cases annually. It is transmitted by Aedes mosquito which infected with a dengue virus. Therefore, predicting the dengue fever rate as become the subject of researches in many tropical countries. Some of them use statistical and machine learning approach to predict the rate of the disease so that the government can prevent that incident. In this study, we explore many models in the statistical learning approaches for predicting the dengue fever rate. We applied several methods in the predictive statistics such as regression, spatial regression, geographically weighted regression and robust geographically weighted regression to predict the dengue fever rate in Surabaya. We then analyse the results, compare them based on the mean square error. Those four models are chosen, to show the global estimator’s approaches, e.g. regression, and the local ones, e.g. geographically weighted regression. The model with the minimum mean square error is regarded as the most suitable model in the statistical learning area for solving the problem. Here, we look at the estimates of the dengue fever rate in the year 2012, to 2017, area, poverty percen­tage, precipitation, number of rainy days for predicting the dengue fever outbreak in the year 2018. In this study, the pattern of the predicted model can follow the pattern of the true dataset.
Eco-Efficiency of Pencil Preduction Using Life Cycle Assessment to Increase the Manufacture Sustainability
Authors: Purwaningsih Ratna , Simanjuntak Christoper Frans , Rosyada Zainal Fanani
Published: August 2020

This study aims to measure the environmental costs (eco-cost) and the eco-efficiency ratio rate (EER) of the production of pencils and formulate some recommendations to improve the manufacture sustainability. The measurement of Eco-efficiency was performed using life cycle assessment (LCA) with the eco-cost method. The pencil manufacturer produces a waste of 20 %, and the product rejects 37 %. The material used is wood, slat, and chemical material for painting. The result of the data processing shows that the eco-costs of IDR 50.593.583 for 4200 grosses production lot size. The eco-efficiency index or EEI for pencil product was 1,69, which means that the products are affordable and sustainable. The eco-efficiency ratio rate (EER) is 41% means that pencil production processes need improvement. The single score Impact Category Diagram shows that the most significant environment impact category is climate change. The recommendation to improve the EER of pencil production based on Impact Category Diagram is (1) to increase the utilizing of wood waste and (2) to increase the capability of technicians and operators to reduce the product rejection. These recommendations aim to reduce the wood consumed in production.
STRATEGI IMC DALAM MEMPROMOSIKAN PROGRAM INTERNASIONAL (Studi kasus di Universitas Kristen Satya Wacana – Salatiga)
Authors: Setiawan William Christianto , Wijaya Lina Sinatra
Published: August 2020

Tujuan penelitian ini yaitu untuk mengetahui strategi Integrated Marketing Communication (IMC) yang digunakan oleh Biro Kerjasama dan Hubungan Internasional (BKHI) Universitas Kristen Satya Wacana (UKSW) dalam menginformasikan sekaligus mempromosikan program internasionalnya kepada mahasiswa UKSW. Penelitian ini berupa penelitian deskriptif kualitatif dengan menggunakan metode studi kasus. Data diperoleh dengan cara melakukan wawancara mendalam, observasi, dan dokumentasi. Hasil penelitian ini menyatakan bahwa segmentasi psikografis dengan melihat motivasi, gaya hidup, dan karakteristik kepribadian terhadap target sasaran dilaksanakan terlebih dahulu sebelum menentukan strategi IMC. Penggunaan kata kata “internasional”, “cultural exchange”, “higher education” dan “beasiswa” digunakan dalam mempromosikan program internasional ini, khususnya dalam pembuatan iklan, sales promotion, humas dan publisitas, personal selling, direct marketing, serta acara dan pengalaman.
PENGGUNAAN MEDIA ONLINE UNTUK BISNIS ONLINE PEMULA PADA PENDERITA HIV
Authors: Nainggolan Romauli , Silitonga Hanna Tabita Hasianna , Rambung Etha
Published: August 2020

Penelitian ini meneliti dampak pelatihan pada penciptaan bisnis online untuk pemula dengan peserta yang berasal dari ibu rumah tangga yang terpajan HIV. Metode yang digunakan dalam penelitian ini adalah metode penelitian kualitatif. Informan dalam penelitian ini adalah 5 ibu rumah tangga. Data dikumpulkan dengan menggunakan teknik wawancara terstruktur langsung dengan metode pre-test dan post-test sesudahnya. Semua informan tidak pernah melakukan bisnis menggunakan media online atau mengetahui cara berbisnis menggunakan media online. Hasil penelitian menunjukkan (1) peningkatan pengetahuan dan keterampilan 50% menggunakan media situs web Facebook. (2) Ada peningkatan dan keterampilan 83% menggunakan media sosial WhatsApp. (3) Aspek komparatif dari pemasaran dan penjualan produk menggunakan media sosial WhatsApp memiliki hasil yang lebih tinggi daripada media situs web Facebook. Ini karena waktu yang terbatas untuk menguasai semua fitur di media online.This research examines the impact of training on online business creation for beginners with the participants coming from HIV-exposed housewives. The method used in this research is the qualitative research method. Informants in this research are 5 housewives. The data was collected using direct structured interviews technique with pre-test and post-test methods afterwards. All informants have never done business using online media nor knowing how to do business using online media. The results showed (1) an increase in knowledge and skills of 50% using the Facebook website media. (2) There was an increase and skills of 83% using WhatsApp social media. (3) Comparative aspects of marketing and product sales using WhatsApp social media have higher results than the Facebook website media. This is due to limited time to master all the features in online media.
PENINGKATAN KUALITAS PRODUK UKM KERAJINAN KULIT KERANG DI KENJERAN KOTA SURABAYA
Authors: Kartika Yuliar , Mujanah Siti
Published: August 2020

Kegiatan pengabdian masyarakat ini dilakukan terhadap UMKM mitra di bidang Pengrajin dari bahan kulit kerang di Kenjeran Kota Surabaya. UMKM ini memiliki jumlah karyawan sebanyak 5 orang, kegiatan yang dilakukan adalah menjual bahan kulit kerang yang sudah di poles, membuat pigura, tempat tisu dan kerajinan lainnya. Selama ini mereka berproduksi dengan peralatan yang ada namun sudah pada rusak untuk itu kualitas maupun kuantitas produk yang dihasilkan kurang maksimal, Untuk itulah Program Kegiatan Pengabdian masyarakat ini lakukan dengan memberikan pelatihan di bidang pengembangan produk, pengadaan peralatan berupa 1 (satu) unit gergaji triplek dan 1 (satu) unit mesin bor untuk kerang. Setelah mesin di berikan maka di lakukan pelatihan penggunaannya, disamping itu juga dilakukan Pelatihan di bidang peningkatan kualitas produk, pengelolaan usaha, pemasaran dan pembukuan keuangan. Dan hasilnya adalah mitra mampu mengelola usaha dengan efisien dan efektif, mereka juga mampu memasarkan produk serta memiliki pembukuan keuangan yang semula belum ada catatan keuangan sama sekali.This community service activity was carried out on partner SMEs in the field of Crafts from shells in Kenjeran, Surabaya. This UMKM has 5 employees, the activities being carried out are selling shells that have been polished, making frames, tissue boxes and other handicrafts. During this time they produce with existing equipment but it is already broken for that the quality and quantity of products produced is less than optimal. 1 (one) drilling machine unit for shells. After the machine is given, training on its use is carried out, besides that it also conducts training in the areas of product quality improvement, business management, marketing and financial accounting. And the result is that partners are able to manage their businesses efficiently and effectively, they are also able to market their products and have financial records that originally had no financial records at all.
Engineering Surface Atomic Architecture of NiTe Nanocrystals Toward Efficient Electrochemical N2 Fixation
Authors: Yuan Menglei , Li Qiongguang , Zhang Jingxian , Wu Jiawen , Zhao Tongkun , Liu Zhanjun , Zhou Le , He Hongyan , Li Bin , Zhang Guangjin
Published: August 2020

Efficient N2 fixation at ambient condition through electrochemical processes has been regarded as a promising alternative to traditional Haber–Bosch technology. Engineering surface atomic architecture of the catalysts to generate desirable active sites is important to facilitate electrochemical nitrogen reduction reaction (NRR) while suppressing the competitive hydrogen evolution reaction. Herein, nickel telluride nanocrystals with selectively exposed {001} and {010} facets are synthesized by a simple process, realizing the manipulation of surface chemistry at the atomic level. It is found that the catalysts expose the {001} facets coupled with desirable Ni sites, which possess high Faraday efficiency of 17.38 ± 0.36% and NH3 yield rate of 33.34 ± 0.70 μg h−1 mg−1 at ‐0.1 V vs RHE, outperforming other samples enclosed by {010} facets (8.56 ± 0.22%, 12.78 ± 0.43 μg h−1 mg−1). Both experimental results and computational simulations reveal that {001} facets, with selectively exposed Ni sites, guarantee the adsorption and activation of N2 and weaken the binding for *H species. Moreover, the enhanced reduction capacity and accelerated charge transfer kinetics also contribute the superior NRR performance of {001} facets. This work presents a novel strategy in designing nonprecious NRR electrocatalyst with exposed favorable active sites.
Tuning Transport and Chemical Sensitivity via Niobium Doping of Synthetic MoS2
Authors: Zhang Kehao , Deng Donna D. , Zheng Boyang , Wang Yuanxi , Perkins F. Keith , Briggs Natalie C. , Crespi Vincent H. , Robinson Joshua A.
Published: August 2020

Beyond the intrinsic properties of 2D materials, another advantage is the tunability that follows from their low dimensionality. Here, large‐area Nb‐doped MoS2 monolayer films deposited by metal organic chemical vapor deposition that can function as electrical contacts or chemical sensors are demonstrated. Compared to pristine MoS2, Nb‐doped MoS2 exhibits a relatively faster growth rate and quenched PL due to formation of mid‐gap energy bands. When the Nb concentration reaches 5 at%, doped MoS2 shows clear p‐type characteristics, evident by a 1.7 eV shift of the Fermi level toward the valence band maximum. Doping also impacts transport at the metal/MoS2 interface, demonstrated by Pt–Ir metallization that is Schottky‐limited when in contact with undoped MoS2 but Ohmic on Nb‐MoS2. Moreover, a 50 × improved signal‐to‐noise ratio is demonstrated in sensing triethylamine compared to undoped MoS2, with <15 parts‐per‐billion detection limit.
High‐Throughput and Controllable Fabrication of Soft Screen Protectors with Microlens Arrays for Light Enhancement of OLED Displays
Authors: Ding Yekai , Lin Yinyin , Zhao Lidan , Xue Chang , Zhang Mengying , Hong Yaying , Peng Suili , Wen Weijia , Wu Jinbo
Published: August 2020

In this work, soft polydimethylsiloxane (PDMS) screen protectors with microlens arrays (MLAs) are fabricated through a feasible high‐throughput approach. Based on the lateral size scaling effect during discontinuous dewetting, desired SU‐8 convex MLAs with simultaneously controlled focal length (f) and numerical aperture (NA) are produced on a single substrate. A replication technique is employed to prepare PDMS MLAs with the same structure as that of the SU‐8 MLAs. The contact angle and other optical parameters of the MLAs can be tuned over a wide range based on the number of sliding times and lateral size. When the diameter of the MLAs decreases from 100 to 10 µm, the curvature changes from 0.07 to 0.17 for the single‐layer MLAs and from 0.15 to 0.31 for the three‐layer MLAs. The enhancement effect of MLAs on the light from wide‐angle organic light‐emitting diode (OLED) packaging modules is investigated. It is found that PDMS films containing MLAs can increase the brightness of an OLED by 14.13%. The fabricated PDMS concave MLAs can serve as flexible screen protectors to shield OLEDs from damage while enhancing the brightness to improve the energy efficiency.
Energy‐Harvesting Blue Color Filters for Organic Light‐Emitting Diodes
Authors: Jeong Soyeong , Kim Seonghee , Kang Hongkyu , Lee Kwanghee
Published: August 2020

Color filters are essential components to realize next‐generation applications based on organic light‐emitting diodes (OLEDs), such as flexible displays and multipurpose lighting. Although the most widely used color filters that include dyes and pigments have advantageous features, such as their simplicity and color purity, the energy wasted by these color filters does not meet the needs for a green and sustainable future. This paper presents a fullerene‐free organic solar cell (OSC) color filter that is not only a highly effective blue color filter, owing to its ability to absorb green and red light, but also functions as an energy‐harvesting device. OLED‐OSC tandem devices with the two distinct functions of OLED and OSC within one device are successfully demonstrated. The OSC of the tandem device generates electrical energy with a power conversion efficiency of 6.83%. The OLED of the tandem device emits blue light with a maximum luminance of 1400 cd m−2, and the International Commission on Illumination (CIE) chromaticity is dramatically tunable from (0.34, 0.36) to (0.14, 0.17).
Enantioselective Organocatalytic Synthesis of δ‐Lactone‐Fused 4‐Chromanones
Authors: Lai Yu‐Ting , Nagaraju Koppanathi , Gurubrahamam Ramani , Chen Kwunmin
Published: August 2020

An organocatalytic enantioselective synthesis of δ‐lactone‐fused 4‐chromanones was demonstrated using 1‐(2‐hydroxyaryl)‐1,3‐butanedione and α,β‐unsaturated aldehydes in the presence of the Jørgensen‐Hayashi catalyst. The reaction proceeded through a Michael addition/cycloketalization/hemiacetalization sequence, and the resulting hemiacetals were oxidized into the corresponding lactone derivatives in a one‐pot manner. The desired fused O,O‐ketal tricyclic lactone motifs containing three contiguous chiral centers were obtained in excellent chemical yields (up to 97%) and with high stereoselectivities (up to >20:1 dr and up to 95% ee).

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Electrochemical CO2 Reduction: Tailoring Catalyst Layers in Gas Diffusion Electrodes
Authors: Junge Puring Kai , Siegmund Daniel , Timm Jana , Möllenbruck Florian , Schemme Steffen , Marschall Roland , Apfel Ulf‐Peter
Published: August 2020

The electrochemical conversion of CO2 into commodity chemicals or fuels is an attractive reaction for sustainable CO2 utilization. In this context, the application of gas diffusion electrodes is promising due to efficient CO2 mass transport. Herein, a scalable and reproducible method is presented for polytetrafluoroethylene (PTFE)‐bound copper gas diffusion electrodes (GDEs) via the dry‐pressing method and compositional parameters are emphasized to alter such electrodes. The assembly of the catalytic layer plays a critical role in the electrode performance, as elevated bulk hydrophobicity coupled with good surface wettability is observed to offer highest performance in 0.5 m KHCO3. With optimized electrodes, formate, CO, and H2 are obtained at a current density of 25 mA cm−2 as main products in 1 m KOH in faradaic efficiencies (FEs) of 27%, 30%, and 36%. At 200 mA cm−2, an altered product composition with ethylene (33% FE) and ethanol (9% FE) along with H2 (33% FE) is observed. In addition, n‐propanol is observed with 7% faradaic efficiency. The results indicate that the composition of the GDE has a severe influence on the electrode performance and setting proper hydrophobicity gradients within the electrode is key toward developing a successful electrochemical CO2 reduction.
Developing Oxygen Carriers for Chemical Looping Biomass Processing: Challenges and Opportunities
Authors: Yu Lei , Zhou Wei , Luo Zhenyi , Wang Haiming , Liu Wen , Yin Ke
Published: August 2020

Among the various thermochemical biomass conversion pathways, chemical looping gasification and chemical looping reforming, collectively known as chemical looping biomass processing (CLBP), offers numerous advantages, including the generation of renewable hydrogen, high exergy efficiency, inherent carbon capture, and process intensification. Like all other chemical looping applications, oxygen carriers play key roles in determining the effectiveness and efficiency of CLBP. In addition to the requirement for high oxygen transfer capacity, the chemical activity of the lattice oxygen also needs to be modulated to steer the selectivity of CLBP toward syngas. Furthermore, it is desirable for the CLBP oxygen carriers to possess catalytic activities that accelerate the conversion of biomass‐based feedstocks. However, despite the large volume of relevant research publications, the diversity in oxygen carrier formulations, biomass compositions, and test conditions used leads to mixed views regarding the structural–functional relationships between oxygen carriers and their performance during CLBP. To address the above knowledge gap, this review presents a systematic, but non‐exhaustive summary of the development and evaluation of oxygen carriers for CLBP applications, with an aim to elucidate the rational design principles and operation parameters toward optimal process efficiency.
Two‐Phase Colloidal Synthesis of Amorphous Iron‐Doped Manganese Phosphate Hollow Nanospheres for Efficient Water Oxidation
Authors: Liu Yan , Zhang Jifu , Wang Wei , Cao Lixin , Dong Bohua
Published: August 2020

Exploitation of earth‐abundant, efficient and stable electrocatalysts is of great significance for the oxygen evolution reaction (OER). Herein, a facile two‐phase colloidal method is developed to synthesize amorphous iron‐doped manganese phosphate (a‐Fe‐Mn:Pi) hollow nanospheres for the first time. Due to the synergistic interplay of hollow nanosphere morphology, amorphous structural character, and iron doping, the a‐Fe‐Mn:Pi catalyst possesses high electrochemically active surface area and excellent conductivity. As a consequence, the obtained a‐Fe‐Mn:Pi sample displays superior OER activity in alkaline condition with a small overpotential of 252 mV at 10 mA cm−2 and a Tafel slope of 52.0 mV decade−1 as well as 93.3% retention of the initial current density even after 20 h of reaction time. This work provides a new perspective on the design of hollow nanostructures for catalytic applications.
Integrated and Binder‐Free Air Cathodes of Co3Fe7Nanoalloy and Co5.47N Encapsulated in Nitrogen‐Doped Carbon Foam with Superior Oxygen Reduction Activity in Flexible Aluminum‐Air Batteries
Authors: Jiang Min , Fu Chaopeng , Cheng Ruiqi , Zhang Wei , Liu Tongyao , Wang Ruibin , Zhang Jiao , Sun Baode
Published: August 2020

All‐solid‐sate Al‐air batteries with features of high theoretical energy density, low cost, and environmental‐friendliness are promising as power sources for next‐generation flexible and wearable electronics. However, the sluggish oxygen reduction reaction (ORR) and poor interfacial contact in air cathodes cause unsatisfied performance. Herein, a free‐standing Co3Fe7nanoalloy and Co5.47N encapsulated in 3D nitrogen‐doped carbon foam (Co3Fe7@Co5.47N/NCF) is prepared as an additive‐free and integrated air cathode for flexible Al‐air batteries in both alkaline and neutral electrolytes. The Co3Fe7@Co5.47N/NCF outperforms commercial platinum/carbon (Pt/C) toward ORR with an onset potential of 1.02 V and a positive half‐wave potential of 0.92 V in an alkaline electrolyte (0.59 V in sodium chloride solution), which is ascribed to the unique interfacial structure between Co3Fe7and Co5.47N supported by 3D N‐doped carbon foam to facilitate fast electron and mass transfer. The high ORR performance is also supported by in‐situ electrochemical Raman spectra and density functional theory calculation. Furthermore, the fabricated Al‐air battery displays good flexibility and delivers a power density of 199.6 mW cm−2, and the binder‐free and integrated cathode shows better discharge performance than the traditionally slurry casting cathode. This work demonstrates a facile and efficient approach to develop integrated air cathode for metal‐air batteries.
Extrusion 3D Printing of Polymeric Materials with Advanced Properties
Authors: Jiang Zhen , Diggle Broden , Tan Ming Li , Viktorova Jekaterina , Bennett Christopher W , Connal Luke A.
Published: August 2020

3D printing is a rapidly growing technology that has an enormous potential to impact a wide range of industries such as engineering, art, education, medicine, and aerospace. The flexibility in design provided by this technique offers many opportunities for manufacturing sophisticated 3D devices. The most widely utilized method is an extrusion‐based solid‐freeform fabrication approach, which is an extremely attractive additive manufacturing technology in both academic and industrial research communities. This method is versatile, with the ability to print a range of dimensions, multimaterial, and multifunctional 3D structures. It is also a very affordable technique in prototyping. However, the lack of variety in printable polymers with advanced material properties becomes the main bottleneck in further development of this technology. Herein, a comprehensive review is provided, focusing on material design strategies to achieve or enhance the 3D printability of a range of polymers including thermoplastics, thermosets, hydrogels, and other polymers by extrusion techniques. Moreover, diverse advanced properties exhibited by such printed polymers, such as mechanical strength, conductance, self‐healing, as well as other integrated properties are highlighted. Lastly, the stimuli responsiveness of the 3D printed polymeric materials including shape morphing, degradability, and color changing is also discussed.
Aerobic oxidation of benzyl alcohol in a slug flow microreactor: Influence of liquid film wetting on mass transfer
Authors: Hommes Arne , Disselhorst Bas , Yue Jun
Published: August 2020

Homogeneous Co/Mn/Br catalyzed aerobic oxidation of benzyl alcohol in acetic acid to benzaldehyde was performed in polytetrafluoroethylene microreactors operated under slug flow at temperatures up to 150°C and pressures up to 5 bar. Depending on the bubble velocity and length, a wetted or dewetted slug flow was observed, characterized typically by a complete or partially wetting liquid film around the bubble body. The latter flow suffered from a limited interfacial area for mass transfer. Experiments at temperatures up to ca. 90°C were under kinetic control given no product yield difference under wetted and dewetted slug flows and were used to establish a simplified kinetic expression (first order in benzyl alcohol and zero order in oxygen). This allows to develop a mass transfer model combined with an instantaneous reaction regime that well described the experimental results at higher temperatures where mass transfer was limiting in the dewetted slug flow.
Sulfonyl PIM‐1: A diverse separation membrane with dilation resistance
Authors: Anstine Dylan M. , Mendez Nicholas F. , Colina Coray M.
Published: August 2020

A sulfone modified variant (soPIM‐1) of the first polymer of intrinsic microporosity has been studied through molecular simulations to analyze its applicability for adsorption‐based separations of diverse nonpolar, quadrupolar, and dipolar adsorbate species. Single component gas phase adsorption isotherms of each adsorbate are provided. The adsorptive properties of soPIM‐1 are reported from the application of two methods: (a) traditional grand canonical Monte Carlo (GCMC) simulations and (b) a combination of Monte Carlo and molecular dynamics (GCMC/MD) techniques, which accounts for sorption‐induced polymer dynamics. The calculated isosteric heats of adsorption are compared to those from the parent PIM‐1 structure and reveals increased CO2 affinity with relatively no change in hydrocarbon affinity. Moreover, to quantify soPIM‐1's resistance to dilation the evolution of the microporous structure across the adsorption isotherm loading pressures has been evaluated. Relatedly, nonequilibrium MD simulations have been utilized to determine that soPIM‐1 is approximately twice as stiff as PIM‐1.
The Na⋅⋅⋅B Bond in NaBH3−: A Different Type of Bond
Authors: Foroutan‐Nejad Cina
Published: August 2020

A newly introduced Na−B bond in NaBH3−has been a challenge for the chemical bonding community. Here, a series of MBH3−(M=Li, Na, K) species and NaB(CN)3−are studied within the context of quantum chemical topology approaches. The analyses suggest that M–B interaction cannot be classified as an ordinary covalent, dative, or even simple ionic interaction. The interactions are controlled by coulombic forces between the metals and the substituents on boron, for example, H or CN, more than the direct M–B interaction. On the other hand, while the characteristics of the (3, −1) critical points of the bonds are comparable to weak hydrogen bonds, not covalent bonds, the metal and boron share a substantial sum of electrons. To the best of the author's knowledge, the characteristics of these bonds are unprecedented among known molecules. Considering all paradoxical properties of these bonds, they are herein described as ionic‐enforced covalent bonds.
Preparation and characterization of imidazolyl ionic liquid‐based shear thickening dispersion system
Authors: Cao Chuanzhi , Luo Yan , Xiao Min
Published: August 2020

Shear thickening liquid (STF) is a new nonNewtonian fluid widely used in industrial production. In this paper, a novel shear thickening and dispersing system, namely poly methyl methacrylate (PMMA)/1‐butyl‐3‐methylimidazole hexa‐fluorophosphate ([BMIM]PF6), was prepared using ultrasonic with PMMA as the dispersing phase and [BMIM]PF6 as the dispersing medium. The stability, thixotropic, reversibility, rheology, and viscoelasticity of the dispersion system was studied, respectively. The dispersed system has good stability. The dispersed system shows high response sensitivity to shear rate, as well as good reversibility to shear thickening. Compared with traditional silicon dioxide/polyethylene glycol dispersion system, PMMA/[BMIM]PF6 dispersion system displays a significantly enhanced shear thickening effect. Nonionic surfactant triton X‐100 of 4 wt% can greatly improve PMMA/[BMIM]PF6 dispersion system's shear thickening behavior. This paper provides a new idea for the further development of protective materials by using STF.
Vapor deposition polymerization of synthetic rubber thin film in a plasma enhanced chemical vapor deposition reactor
Authors: Gürsoy Mehmet
Published: August 2020

Rubber is one of the most commonly used industrial materials worldwide. However, there is a gap in the literature on the production of rubber thin films in nanoscale. When the rubber thin films are produced in nanoscale, they can be used in high‐tech applications where bulk rubbers have never been used before. This study is one of the first investigations to focus on the vapor‐based production of the polyisoprene (PI), which is an important member of the synthetic rubber class. For this purpose, a single‐step, rapid and environmentally friendly method based on plasma enhanced chemical vapor deposition (PECVD) was employed to produce PI thin films using 2‐methyl‐1,3‐butadiene (isoprene). The high‐vapor pressure of isoprene makes it a promising monomer for the production of chemical vapor deposition polymers. The effect of plasma processing parameters on the PI deposition rate was investigated. The deposition rate of PI thin film as high as 40 nm/min was achieved and the contact angle of PI coated bamboo surface was found to be 146.8°. The mechanical durability and laundering tests of PI thin films were performed. Based on this study results, PI thin films produced by PECVD can be used in a number of potential applications.
Design, synthesis, and cytotoxicity screening of new synthesized imidazolidine‐2‐thiones as VEGFR‐2 enzyme inhibitors
Authors: Zaki Islam , Ramadan Heba M. M. , El‐Sayed El‐Sherbiny H. , Abd El‐Moneim Mohamed
Published: August 2020

A series of imidazolin‐2‐thione derivatives was synthesized and structurally confirmed through the use of different spectroscopic techniques such as infrared, nuclear magnetic resonance, and mass spectrometry along with elemental analyses. The breast cancer cell line MCF‐7 was utilized in the evaluation of the cytotoxic activity of the prepared molecules. The tested molecules 3 and 7 exhibited the best results on MCF‐7 cells, with mean IC50 values of 3.26 and 4.31 µM, respectively. The results of the VEGFR‐2 assay indicated that compounds 3 and 7 displayed a good inhibition of the VEGFR‐2 kinase enzyme. Additionally, DNA flow cytometry of compounds 3 and 7 showed cell cycle arrest at the G0/G1 phase, cell apoptosis, and marked DNA fragmentation in MCF‐7 cells. Finally, compounds 3 and 7 were proved to upregulate the activation of effector caspase‐3/7, as presented by the caspase‐3/7 green flow cytometry assay.
The Fe4+/3+ Redox Mechanism in NaFeO2: A Simultaneous Operando Nuclear Resonance and X‐ray Scattering Study
Authors: Fehse Marcus , Bessas Dimitrios , Mahmoud Abdelfattah , Diatta Aliou , Hermann Raphael P. , Stievano Lorenzo , Sougrati Moulay Tahar
Published: August 2020

Simultaneous operando Nuclear Forward Scattering and transmission X‐ray diffraction and 57Fe Mössbauer spectroscopy measurements were carried out in order to investigate the electrochemical mechanism of NaFeO2 vs. Na metal using a specifically designed in situ cell. The obtained data were analysed using an alternative and innovative data analysis approach based on chemometric tools such as Principal Component Analysis (PCA) and Multivariate Curve Resolution ‐ Alternating Least Squares (MCR‐ALS). This approach, which allows the unbiased extraction of all possible information from the operando data, enabled the stepwise reconstruction of the independent “real” components permitting the description of the desodiation mechanism of NaFeO2. This wealth of information allows a clear description of the electrochemical reaction at the redox‐active iron centres, and thus an improved comprehension of the cycling mechanisms of this material vs. sodium.
Bilateral middle cerebellar peduncle lesions: Neuroimaging features and differential diagnoses
Authors: Jiang Jiwei , Wang Jirui , Lin Meiqing , Wang Xiaoting , Zhao Jinli , Shang Xiuli
Published: August 2020

Objectives

Lesions limited to the bilateral middle cerebellar peduncles (MCPs) are uncommon. This retrospective study investigated diseases with a proclivity for the bilateral MCPs and explored the associations between their neuroimaging features and clinical findings for the differential diagnosis of such lesions.

Methods

We enrolled 26 patients who were admitted to our department between January 2016 and March 2019 with bilateral MCP abnormalities on magnetic resonance imaging (MRI). The demographic, clinical, and neuroimaging characteristics, and the biomarkers and diagnoses were evaluated.

Results

Although all patients exhibited symmetrical bilateral MCP hypointensities on T1‐weighted imaging and hyperintensities on T2‐weighted and fluid‐attenuated inversion recovery imaging, they were diagnosed with different conditions. Diagnoses included acute cerebral infarction (ACI) (n = 9, 34.62%), Wallerian degeneration (WD) (n = 8, 30.77%), multiple system atrophy (MSA) (n = 6, 23.08%), neuromyelitis optica (NMO) (n = 1, 3.85%), heroin‐induced leukoencephalopathy (n = 1, 3.85%), and primary central nervous system lymphoma (PCNSL) (n = 1, 3.85%). Patients with ACI exhibited bilateral MCP‐restricted diffusion hyperintensities on diffusion‐weighted imaging and corresponding stenosis or occlusion of the vertebrobasilar system. The initial MRI of patients with WD depicted pontine infarctions, while symmetrical MCP lesions were observed on follow‐up MRI. Symmetrical MCP lesions, cruciform hyperintensity, and marked atrophy in the posterior fossa were characteristic manifestations of MSA. Longitudinally extensive myelitis affecting more than three vertebral segments on cervical MRI and positive serum AQP4‐IgG may be indicative of NMO. Heroin‐induced leukoencephalopathy was characterized by extra‐symmetrical lesions in the posterior limbs of the internal capsules, while the anterior limbs were spared. PCNSL was indicated by a significant and characteristic “fist” sign on contrast‐enhanced MRI.

Conclusions

Bilateral MCP lesions were most frequently observed in cerebrovascular diseases, followed by neurodegenerative diseases, inflammatory diseases, toxic encephalopathies, and lymphomas. Our findings demonstrate that bilateral MCP signal abnormalities are more common in patients with ACI and WD, with fewer degenerative processes than previously believed. The high frequency of WD may be attributed to the specific awareness of this pathology. WD can also present with stage‐related restricted diffusion and should not be mistaken for a new infarction. The symmetrical bilateral MCP hypointensities on T1‐weighted imaging and hyperintensities on T2‐weighted imaging often raise concern regarding a demyelinating process. Our findings emphasize that neurologists should consider the aforementioned conditions and correlate the specific neuroimaging characteristics and medical history before arriving at the final diagnosis.
Critical success factors for a circular economy: Implications for business strategy and the environment
Authors: Moktadir Md. Abdul , Kumar Anil , Ali Syed Mithun , Paul Sanjoy Kumar , Sultana Razia , Rezaei Jafar
Published: August 2020

Eco‐efficiency and resource optimization for business strategy and the environment can be achieved by the circular economy (CE) practices in supply chains (SCs). The leather industry is a significant industrial contributor to the economic growth of some countries, but at the same time, it leads to tremendous environmental pollution. This research focuses on the identification and evaluation of critical success factors (CSFs) needed in the business strategy development of CE practices as well as to minimize environmental pollution in leather industry SCs. The CSFs are identified via a comprehensive literature review and are validated by experts' opinions. The validated CSFs are further analyzed using the best–worst method (BWM) and the decision‐making trial and evaluation laboratory (DEMATEL). The BWM is used to identify the weights of the CSFs, and DEMATEL is used to determine the cause–effect relationship between the CSFs. The findings show that “leadership and top management commitment” is the most important CSF. Six CSFs are classified as causal towards CE practices: “leadership and top management commitment,” “strong legislation towards CE practices,” “ecological scarcity of resources,” “knowledge of CE practices,” “funding support for R&D from the government,” and “competitor pressure on CE practices.” The findings of this study can help managers in the leather industry implement CE practices in their existing SCs to minimize waste.
Coronary artery dissection following radiofrequency ablation for atrial fibrillation: Case report and review of the literature
Authors: Reddy S Ashwin , V. Khialani Bharat , Kyranis Stephen , P. Hoole Stephen
Published: August 2020

Coronary artery injury following catheter ablation for cardiac arrhythmias is very rare. We present a case of left circumflex (LCx) coronary artery dissection causing inferoposterior ST‐elevation myocardial infarction following radiofrequency (RF) ablation for atrial fibrillation (AF) in a 39‐year‐old male with no cardiovascular risk factors. This was confirmed on coronary angiography and intracoronary vascular ultrasound (IVUS). The likely etiology is thermal injury during RF ablation for AF, due to the close proximity of the left atrial appendage and left pulmonary veins to the LCx. He was successfully treated with primary percutaneous coronary intervention with good outcome. This is, to our knowledge, the first reported case of proven acute coronary dissection secondary to RF ablation for AF reported in the literature, and highlights the importance of considering this as a mechanism for coronary occlusion in these patients.
COVID‐19 pneumonia with back pain: Presentation of an acute pulmonary embolism associated with novel coronavirus infection in an outpatient setting
Authors: Davis Kenyani
Published: August 2020

The Chinese Center for Disease Control and Prevention reported 80% of coronavirus infections were mild cases; hence, most cases will be managed in an outpatient setting. COVID‐19 is associated with a hypercoagulable state; therefore, further research should be done on outpatient use of anticoagulation for VTE/PE prophylaxis in these patients.
Hierarchy Concepts in Design and Synthesis of Nanocatalysts
Authors: Zeng Hua Chun
Published: August 2020

High‐performance catalytic nanomaterials (nanocatalysts) are normally more complex than their phase‐pure counterparts in terms of preparation processes and physicochemical properties. Therefore, more thoughtful considerations are required on various hierarchy‐related issues in their design and synthesis, especially when deciding their composition, mass, activity, selectivity, reactivity, stability, surface, texture, porosity, structure, size, shape, density, and even cost for a system under development. In this Concept article, we will address some general considerations and approaches with respect to the design and synthesis of nanocatalysts. In particular, architectural conceivability, materials selection, synthetic technique and integration strategy will be discussed. Furthermore, we will use the development of integrated nanocatalysts as examples to highlight some key hierarchical issues and snapshot a few representative practices. Finally, a number of suggestions regarding future research directions are also proposed on the basis of personal perspective.
MOF‐derived/zeolite hybrid catalyst for the production of light olefins from CO2
Authors: Martín Nuria , Portillo Ander , Ateka Ainara , Cirujano Francisco G. , Oar‐Arteta Lide , Aguayo Andrés T. , Dusselier Michiel
Published: August 2020

In this contribution we propose an alternative catalytic system based on MOF derivatives and small pore zeolites for the selective conversion of CO2 into light olefins, using the lowest metal loadings and highest GHSV reported in literature. The catalyst synthesis involves deriving In−Zr oxides from MOFs containing these metals in their structure, i. e. (Zr)UiO‐67‐bipy‐In, via direct calcination in the presence of the zeolite, avoiding co‐precipitation, washing and mixing steps. This effectively creates a truly bifunctional In−Zr zeolite catalyst, opposed to physical mixtures of two catalysts using different precursors. The good dispersion and low loadings of the MOF‐derived In−Zr oxide supplemented with the strong acidity of chabazite‐type zeolites allows to couple the activation of CO2 with C−C coupling, obtaining space time yields of 0.1 mol of CO2 converted to light olefins per gram of In per hour at 375 °C, under the GHSV conditions employed.
Direct Introduction of an Alkylsulfonamido Group on C‐sites of Isomeric Dicarba‐closo‐dodecaboranes: The Influence of Stereochemistry on Inhibitory Activity against the Cancer‐Associated Carbonic Anhydrase IX Isoenzyme
Authors: Nekvinda Jan , Kugler Michael , Holub Josef , El Anwar Suzan , Brynda Jiří , Pospíšilová Klára , Růžičková Zdeňka , Řezáčová Pavlína , Grüner Bohumír
Published: August 2020

Carbonic anhydrase IX (CA IX), a tumor‐associated metalloenzyme, represents a validated target for cancer therapy and diagnostics. Herein, we report the inhibition properties of isomeric families of sulfonamidopropyl‐dicarba‐closo‐dodecaboranes group(s) prepared using a new direct five‐step synthesis from the corresponding parent cages. The protocol offers a reliable solution for synthesis of singly and doubly substituted dicarba‐closo‐dodecaboranes with a different geometric position of carbon atoms. The closo‐compounds from the ortho‐ and meta‐series were then degraded to corresponding 11‐vertex dicarba‐nido‐undecaborate(1−) anions. All compounds show in vitro enzymatic activity against CA IX in the low nanomolar or subnanomolar range. This is accompanied by clear isomer dependence of the inhibition constant (Ki) and selectivity towards CA IX. Decreasing trends in Ki and selectivity index (SI) values are observed with increasing separation of the cage carbon atoms. Interactions of compounds with the active sites of CA IX were explored with X‐ray crystallography, and eight high‐resolution crystal structures uncovered the structural basis of inhibition potency and selectivity.
Unraveling the Mechanism of the IrIII‐Catalyzed Regiospecific Synthesis of α‐Chlorocarbonyl Compounds from Allylic Alcohols
Authors: Li Man , Sanz‐Marco Amparo , Martinez‐Erro Samuel , García‐Vázquez Víctor , Mai Binh Khanh , Fernández‐Gallardo Jacob , Himo Fahmi , Martín‐Matute Belén
Published: August 2020

We have used experimental studies and DFT calculations to investigate the IrIII‐catalyzed isomerization of allylic alcohols into carbonyl compounds, and the regiospecific isomerization–chlorination of allylic alcohols into α‐chlorinated carbonyl compounds. The mechanism involves a hydride elimination followed by a migratory insertion step that may take place at Cβ but also at Cα with a small energy‐barrier difference of 1.8 kcal mol−1. After a protonation step, calculations show that the final tautomerization can take place both at the Ir center and outside the catalytic cycle. For the isomerization–chlorination reaction, calculations show that the chlorination step takes place outside the cycle with an energy barrier much lower than that for the tautomerization to yield the saturated ketone. All the energies in the proposed mechanism are plausible, and the cycle accounts for the experimental observations.
Multifunctional chiral aminophosphines for enantiodivergent catalysis in a palladium‐catalyzed allylic alkylation reaction
Authors: Eliseenko Sviatoslav S. , Bhadbhade Mohan , Liu Fei
Published: August 2020

Trifunctional MAP‐based chiral phosphines were tested as new ligands in a Pd‐catalyzed asymmetric allylic alkylation, demonstrating fast and enantiodivergent catalysis. The palladium complexes of representative ligands by X‐ray analysis revealed a novel mode of P,N‐coordination of the ligand to the palladium center, which may contribute to switching the sense of the asymmetric induction via combined steric and tunable H‐bonding interactions between the metal complex and the substrates.
Zucker aus dem Automaten
Authors: Feil Sylvia
Published: August 2020

Polysaccharide sind in der Natur allgegenwärtig und zugleich auf molekularer Ebene noch wenig erforscht. Das liegt nicht zuletzt an den langen Ketten, die oft verzweigt sind, sodass der Reinstoff für Struktur‐Eigenschafts‐Untersuchungen schwer zu gewinnen ist. Daher bieten synthetische Polysaccharide hier einen vielversprechenden Zugang.