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Synthesis and Crystal Structure of 4,4′-Diamino-N,N′-diethyl Bisbenzenesulfamide

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Chinese Journal of Structural Chemistry 2007年第2期26卷 177-183页

作者： WANG Li-Min PAN xiao-juan FAN Zhao-yu YANG Liu-Bo LIU Lian TIAN He Laboratory for Advanced Materials Institute of Fine ChemicalsEast China University of Science and Technology Shanghai 200237 China

A new compound of 4,4＇-diamino-N,V＇-diethyl bisbenzenesulfamide （C18H26N4O4S2, Fw = 426.55） has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to the monoclinic system, space group P21/c with a = 10.0623（9）, b = 13.6759（13）, c =15.5309（14） A, β = 100.482（2）°, V= 2101.6（3） A^3, Dc = 1.348 g/cm^3, F（000） = 904, μ = 0.285 mm^-1, Z = 4, the final R = 0.0512 and wR = 0.1363 for 3485 observed reflections with I 〉 2σ（I）. The structure of the title compound is pseudo secondary axisymmetric, and the two sulfamide-groups show distorted tetrahedral configurations.

关键词： 4,4'-diamino-N,V'-diethyl bisbenzenesulfamide synthesis crystal structure

Characterization and functional analysis of hsp18.3 gene in the red flour beetle, Tribolium castaneum

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Insect Science 2019年第2期26卷 263-273页

作者： Jia Xie Xing-Xing Hu Meng-Fan Zhai xiao-juan yu xiao-Wen Song Shan-Shan Gao Wei Wu Bin Li Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life Sciences Nanjing Normal University Nanjing China

Small heat shock proteins (sHSPs) are diverse and mainly function as molecular chaperones to protect organisms and cells from various stresses. In this study, hsp 18.3, one Tribolium castaneum species-specific shsp、has been identified. Quantitative real-time polymerase chain reaction illustrated that Tchsp 18.3 is expressed in all developmental stages, and is highly expressed at early pupal and late adult stages, while it is highly expressed in ovary and fat body at the adult period. Moreover, it was up-regulated 4532 ± 396-fold in response to enhanced heat stress but not to cold stress;meanwhile the lifespan of adults in ds-Tchsp 18.3 group reduced by 15.8% from control group under starvation. Laval RNA interference (RNAi) of Tchsp 18.3 caused 86.1%±4.5% arrested pupal eclosion and revealed that Tchsp 18.3 played an important role in insect development. In addition, parental RNAi of Tchsp 18.3 reduced the oviposition amount by 94.7%. These results suggest that Tchsp 18.3 is not only essential for the resistance to heat and starvation stress, but also is critical for normal development and reproduction in T. castaneum.

关键词： development reproduction stress Tchspl8.3 Tribolium castaneum

A Study on Idea Adoption Prediction Model Based on SMOTE-AdaBoost:Taking Salesforce Platform as an Example

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Journal of Systems Science and Information 2024年第4期12卷 476-490页

作者： yunjiang XI Futao HUANG Lu HUANG xiao LIAO juan yu School of Business Administration South China University of TechnologyGuangzhou 510641China School of Internet Finance and Information Engineering Guangdong University of FinanceGuangzhou 510521China School of Economics and Management Fuzhou UniversityFuzhou 350108China

In the context of information overload,companies often struggle to effectively identify valuable ideas on their open innovation *** this article,we propose an idea adoption strategy based on machine *** used data from a well-known open innovation platform,Salesforce,and extracted characteristic variables using the Information Adoption *** classification models were then constructed based on AdaBoost,Random Forest,SVM and Logistic Regression *** to significant differences in the number of positive and negative samples in the OIP,we used the SMOTE method to address the problem of data *** results of the study showed that the ensemble learning models were more accurate in identifying valuable ideas than the individual machine learning *** comparing the two ensemble learning models,AdaBoost outperformed Random Forest in predicting both positive and negative class *** SMOTE-AdaBoost model achieved a recall of 0.93,a precision of 0.92 and an impressive AUC of 0.98 in identifying adopted ideas,which could well identify valuable ideas and has implications for improving the efficiency and quality of idea adoption in *** shortcoming of this work is that it only investigated a single *** the future,we will consider extending this method to different platforms and multiple classification problems.

关键词： open innovation platform AdaBoost information adoption ensemble learning

Progress on gas-solid phase photoreactor and its application in CO_(2) reduction

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Green Chemical Engineering 2024年第3期5卷 290-306页

作者： Litian Liu yunlong Li Jialun He Qing Wang juan Deng xiao Chen Chao yu School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang212100China

The burgeoning field of photocatalytic reduction of CO_(2)has emerged as a remarkable promising solution to address some of the most pressing global energy and environmental issues which we face *** around the global have been striving to augment the efficiency of CO_(2)photocatalytic reduction,employing strategies that range from modifying the fundamental properties of photocatalysts to suppress the electron-hole recombination,optimizing reaction conditions to achieve the highest yield,and conceptualizing and constructing photoreactors to improve the adsorption *** these factors,the photoreactor plays a critical role in enhancing the overall photocatalytic *** the various types of photoreactors and their operational dynamic can significantly influence the experimental design,thus guiding the data collecting and *** to the solid-liquid phase,gas-solid phase photocatalytic reduction of CO_(2)is gaining recognition for its potential advantages,such as rapid molecular diffusion rates,adjustable CO_(2)concentrations,and uniform and sufficient light ***,the currently reported gas-solid phase photoreactors are still in their *** this review,we dissect the underlying mechanism of photocatalytic CO_(2)reduction and the performance evaluation criteria of photoreactors,and review the development process of gas-solid phase ***,we explore the evolution of gas-solid phase photoreactors,elucidating their growth trajectory and future *** present a comprehensive classification of gas-solid phase photoreactors,offering a new insight into their design and functionality,summarizing their strengths and inevitable ***,we provide a forward-looking perspective on the future developmental prospects of carbon neutrality.

关键词： Photoreactor Gas-solid phase Carbon dioxide reduction Photocatalysis

Constructing oxygen deficiency-rich V_(2)O_(3)@PEDOT cathode for high-performance aqueous zinc-ion batteries

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Rare Metals 2024年第2期43卷 635-646页

作者： Dong-Fei Sun Zi-juan Wang Tian Tian Xin yu Dan-Dan yu xiao-Zhong Zhou Guo-Fu Ma Zi-Qiang Lei Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceSchool of College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China

Aqueous zinc-ion batteries(AZIBs)have attracted widespread attention due to the advantages of high safety and environmental *** V_(2)O_(3) is a promising cathode,the strong electrostatic interaction between Zn^(2+) and V_(2)O_(3) crystal,and the sluggish reaction kinetics still limit their application in ***,the oxygen defects rich V_(2)O_(3) with conducive poly(3,4-ethylenedioxythiophene)(PEDOT)shell(V_(2)O_(3)-Od@PEDOT)was fabricated for AZIBs by combining the sulfur-assisted thermal reduction and in-situ polymerization *** introduced oxygen vacancies of V_(2)O_(3)–Od@PEDOT weaken the electrostatic interaction between Zn^(2+) and the host material,improving the interfacial electron transport,while the PEDOT coating enhances the structural stability and conductivity of V_(2)O_(3),thus accelerating the reaction *** on the advantages,V_(2)O_(3)–Od@PEDOT electrode delivers a reversible capacity of 495 mAh·g^(−1) at 0.1 A·g^(−1),good rate capability(189 mAh·g^(−1)at 8.0 A·g^(−1)),and an impressive cycling stability with 90.1%capacity retention over 1000 cycles at 8.0 A·g^(−1).The strategy may provide a path for exploiting the other materials for high performance AZIBs.

关键词： Oxygen defects V_(2)O_(3) PEDOT Electrochemical self-optimization Aqueous zinc-ion batteries

Research and development of a 0.5-m-long helical superconducting undulator prototype

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-10页

作者： Yang, Xiang-Chen yu, xiao-Wu Wei, Jun-Hao Zhang, Xiang-Zhen Chen, Zi-Lin Bian, xiao-juan Li, He-Ting Feng, Guang-Yao Li, yu-Hui Univ Sci & Technol China Natl Synchrotron Radiat Lab Hefei 230029 Peoples R China Chinese Acad Sci Inst High Energy Phys Beijing 100049 Peoples R China Chinese Acad Sci Inst High Energy Phys China Spallat Neutron Source Dongguan 523000 Peoples R China Chinese Acad Sci Inst Plasma Phys ASIPP Hefei 230031 Peoples R China

The helical undulator is in high demand in synchrotron radiation facilities for circular polarization generation. Owing to the higher field strength provided by the superconducting undulator compared to the conventional permanent-magnet undulator, greater research efforts should be directed toward this area. The helical superconducting undulator holds great potential in synchrotron radiation facilities, especially in low-energy storage rings that seek circularly polarized radiation with the highest possible radiation flux. Following the successful development of planar superconducting undulators, the Institute of High Energy Physics conducted research and development for the helical superconducting undulator. A 0.5-m-long Delta-type superconducting undulator prototype was developed and tested. Detailed information on the design, fabrication, and cryogenic testing of the prototype is presented and discussed.

关键词： Helical Superconducting undulator Delta DESIGN

State-of-the-art on the anchorage performance of rock bolts subjected to shear load

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International Journal of Coal Science & Technology 2024年第1期11卷 1-30页

作者： yu Chen Haodong xiao School of Civil Engineering Sun Yat-sen UniversityZhuhai519082China

Rock bolts are extensively utilized in underground engineering as a means of offering support and stability to rock masses in tunnels,mines,and other underground *** environments of high ground stress,faults or weak zones can frequently arise in rock formations,presenting a significant challenge for engineering and potentially leading to underground engineering *** bolts serve as a crucial structural element for the transmission of tensile stress and are capable of withstanding shear loads to prevent sliding of weak zones within rock ***,a complete understanding of the behavior of rock bolts subjected to shear loads is *** paper presents a state-of-the-art review of the research progress of rock bolts subjected to shear load in three categories:experiment,numerical simulation,and analytical *** review focuses on the research studies and developments in this area since the 1970s,providing a comprehensive overview of numerous factors that influence the anchorage performance of rock *** factors include the diameter and angle of the rock bolt installation,rock strength,grouting material,bolt material,borehole diameter,rock bolt preload,normal stress,joint surface roughness and joint expansion *** paper reviews the improvement of mechanical parameter setting in numerical simulation of rock bolt ***,it delves into the optimization of the analytical model concerning rock bolt shear theory,approached from the perspectives of both Elastic foundation beam theory coupled with Elastoplasticity theory and Structural mechanic *** significance of this review lies in its ability to provide insights into the mechanical behavior of rock *** paper also highlights the limitations of current research and guidelines for further research of rock bolts.

关键词： Rock bolt Shear load Shear test Numerical simulation Analytical model

Polymer-to-Monomers Chemically Recyclable Poly(imide-imine)Plastics with Extreme-Condition Resistance and Flame Retardancy

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Chinese Journal of Polymer Science 2024年第10期42卷 1525-1535,I0012页

作者： Zhen-yu Wang xiao-Kong Liu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Polyimides are a family of high-tech plastics that have irreplaceable applications in the fields of aerospace,defense,and opto-electronics,but polyimides are difficult to be reprocessed and recycled at the end of their service life,resulting in a significant waste of ***,it is of great significance to develop recyclable polyimides with comparable properties to the commercial ***,we report a novel polymer-to-monomers chemically recyclable poly(imide-imine)(PtM-CR-PII)plastic,synthesized by cross-linking the amine-terminated aromatic bisimide monomer and the hexa-vanillin terminated cyclophosphazene monomer via dynamic imine *** PtM-CR-PII plastic exhibits comparable mechanical and thermal properties as well as chemical stability to the commercial *** PtM-CR-PII plastic possesses a high Young’s modulus of≈3.2 GPa and a tensile strength as high as≈108 MPa,which also exhibits high thermal stability with a glass transition temperature of≈220℃.Moreover,the PtM-CR-PII plastic exhibits outstanding waterproofness,acid/alkali-resistance,and solvent-resistance,its appearance and mechanical properties can be well maintained after long-term soaking in water,highly concentrated acid and base,and various organic ***,the cyclophosphazene moieties endow the PtM-CR-PII plastic with excellent flame *** PtM-CR-PII plastic exhibits the highest UL-94 flame-retarding rating of V-0 and a limiting oxygen index(LOI)value of 45.5%.Importantly,the PtM-CR-PII plastic can be depolymerized in an organic solvents-acid mixture medium at room temperature,allowing easy separation and recovery of both monomers in high *** recovered pure monomers can be used to regenerate new PtM-CR-PII plastics,enabling sustainable polymer-monomers-polymer circulation.

关键词： Chemical recyclability Polyimides Polyimines Dynamic imine bonds Mechanical properties Chemical stability

Facile preparation of Fe/N-based biomass porous carbon composite towards enhancing the thermal decomposition of DAP-4

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Defence Technology（防务技术） 2024年第1期31卷 288-294页

作者： Er-hai An xiao-xia Li Cun-juan yu Ying-xin Tan Zi-jun Fan Qing-xia Li Peng Deng Xiong Cao School of Environment and Safety Engineering North University of ChinaTaiyuan030051PR China College of Safety and Emergency Management Engineering Taiyuan University of Science and TechnologyTaiyuan030024PR China

Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was *** porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N ***/Np Carbon was prepared simply by the high-temperature carbonization *** was found that it showed the inherent catalysis properties for thermal decomposition of *** heat release of DAP-4/Fe/N-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/N-p *** decomposition temperature peak of DAP-4 at the presence of Fe/N-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/N-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/*** possible catalytic decomposition mechanism of DAP-4 with Fe/N-p Carbon was proposed.

关键词： Biomass materials Porous carbon DAP-4 Thermal decomposition Facile method