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High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： Li-Dong Qin xin-Yu Wang Qaiser Mahmood zhi-xin Yu Yi-Zhou Wang Song Zou Tong-Ling Liang Wen-Hua Sun School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene

Synchronous deprotonation–protonation for mechanically robust chitin/aramid nanofibers conductive aerogel with excellent pressure sensing, thermal management, and electromagnetic interference shielding

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Nano Research 2024年第3期17卷 2038-2049页

作者： xinxin Zhang Kunpeng Qian Jianhui Fang Sineenat Thaiboonrod Miao Miao xin feng Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Research Center of Nano Science and Technology College of SciencesShanghai UniversityShanghai 200444China School of Materials Sciences and Engineering Shanghai UniversityShanghai 200444China National Nanotechnology Center(NANOTEC) National Science and Technology Development Agency(NSTDA)Thailand Science ParkPathum Thani 12120Thailand

Aerogels with regularly porous structure and uniformly distributed conductive networks have received extensive attention in wearable electronic sensors,electromagnetic shielding,and so ***,the poor mechanical properties of the emerging nanofibers-based aerogels are limited in practical *** this work,we developed a synchronous deprotonation–protonation method in the KOH/dimethyl sulfoxide(DMSO)system at room temperature for achieving chitin cross-linked aramid nanofibers(CANFs)rather than chitin nanofibers(ChNFs)and aramid nanofibers(ANFs)separately by using chitin and aramid pulp as raw *** freeze-drying process,the cross-linked chitin/aramid nanofibers(CA)aerogel exhibited the synergetic properties of ChNF and ANF by the dual-nanofiber compensation *** mechanical stress of CA aerogel was 170 kPa at 80%compressive strain,increased by 750%compared with pure ChNF ***,the compressibility of CA aerogel was somewhat improved compared to ANF *** enhancement verified that the crosslinking reaction between ANF and ChNF during the synchronous deprotonation process was ***,the conductive aerogels with uniform porous structure(CA-M)were successfully obtained by vacuum impregnating CA aerogels in Ti_(3)C_(2)T_(x) MXene solution,displaying low thermal conductivity(0.01 W/(m·K)),high electromagnetic interference(EMI)shielding effectiveness(SE)(75 dB),flame retardant,and heat ***,the as-obtained CA-M aerogels were also applied as a pressure sensor with excellent compression cycle stability and superior human motion monitoring *** a result,the dual-nanofiber based conductive aerogels have great potentials in flexible/wearable electronics,EMI shielding,flame retardant,and heat insulation.

关键词： synchronous deprotonation–protonation electromagnetic interference(EMI)shielding flame retardant heat insulation pressure sensing

Consideration on immunotherapy of liver metastases of malignant tumors

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2374-2381页

作者： Chuang Jiang zhi-Hong Zhang Jia-xin Li Division of Liver Surgery Department of General Surgery and Laboratory of Liver Surgeryand State Key Laboratory of Biotherapy and Collaborative Innovation Center of BiotherapyWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of General Surgery Dafang County People's HospitalBijie 551600Guizhou ProvinceChina

In this editorial,we comment on the article“Analysis of the impact of immuno-therapy efficacy and safety in patients with gastric cancer and liver metastasis”by Liu et al that was published in the recent issue of the World Journal of Gastroin-testinal *** has prompted us to think and summarize some thoughts on immunotherapy for malignant tumor liver *** plays a crucial role in the treatment of malignant tumors;however,the presence of liver metastases in advanced tumors may impact its *** patients with liver metastases can still benefit from immunotherapy,multiple clinical studies have indicated that,compared to other sites of metastasis,liver metastases may diminish the effectiveness of *** efficacy of immune checkpoint inhibitors in patients with liver metastases often fails to reach the ideal level,primarily due to the liver metastases exploiting the host's peripheral immune to-lerance mechanisms to promote systemic CD8(+)T cell exhaustion,resulting in a systemic immune-tolerant *** article aims to summarize the reasons for the decreased efficacy of immunotherapy following liver metastasis in various malignant tumors and propose potential clinical strategies for manage-ment.

关键词： Liver metastasis Immunotherapy Immune tolerance Cancer Treatment

Central environmental protection inspection and carbon emission reduction: A tripartite evolutionary game model from the perspective of carbon neutrality

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Petroleum Science 2024年第3期21卷 2139-2153页

作者： Zhen-Hua Zhang Dan Ling Qin-xin Yang Yan-Chao feng Jing Xiu School of Economics Lanzhou UniversityLanzhou 730000GansuChina Institute of Green Finance Lanzhou UniversityLanzhou 730000GansuChina School of Management Lanzhou UniversityLanzhou 730000GansuChina School of Business Zhengzhou UniversityZhengzhou 450001HenanChina Institute of Economics Jilin Academy of Social SciencesChangchun130033JilinChina

Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction *** study is conducted using a tripartite evolutionary game model to explore the impact of the central environmental protection inspection(CEPI)on driving carbon emission reduction,and to study what factors influence the strategic choices of each party and how they interact with each *** research results suggest that local governments and manufacturing enterprises would choose strategies that are beneficial to carbon reduction when CEPI *** the initial willingness of all parties increases 20%,50%—80%,the time spent for the whole system to achieve stability decreases from 100%,60%—30%.The evolutionary result of“thorough inspection,regulation implementation,low-carbon management”is the best strategy for the tripartite evolutionary ***,the smaller the cost and the larger the benefit,the greater the likelihood of the three-party game stability strategy *** study has important guiding significance for other developing countries to promote carbon emission reduction by environmental policy.

关键词： Central environmental protection inspection Local government Manufacturing enterprise Tripartite evolutionary game Carbon emission reduction

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： feng Ren Zhuang-Zhuang Liang Ming-xin Niu Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

On the Performances of Estimating Stellar Atmospheric Parameters from CSST Broad-band Photometry

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Research in Astronomy and Astrophysics 2024年第4期24卷 161-173页

作者： Rui-feng Shi Yang Huang xin-Yi Li Hua-Wei Zhang School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China CAS Key Lab of Optical Astronomy Key Laboratory of Space Astronomy and TechnologyNational Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China College of Physics and Electronic Engineering Qilu Normal UniversityJinan 250200China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky *** surveys,especially those with near-ultraviolet filters,can offer accurate measurements of stellar parameters,with the precision comparable to that from low/medium resolution *** this study,we explore the capability of measuring stellar atmospheric parameters from Chinese Space Station Telescope(CSST)broad-band photometry(particularly in the near-ultraviolet bands),based on synthetic colors derived from model *** find that colors from the optical and near-ultraviolet filter systems adopted by CSST show significant sensitivities to the stellar atmospheric parameters,especially the *** to our mock data tests,the precision of the photometric metallicity is quite high,with typical values of0.17 and 0.20 dex for dwarf and giant stars,*** precision of the effective temperature estimated from broad-band colors are within 50 K.

关键词： methods:data analysis stars:abundances surveys

Managing immune checkpoint inhibitor-associated gastritis: Insights and strategies

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World Journal of Gastroenterology 2024年第24期30卷 3120-3122页

作者： Li-Li Yu zhi-Lin He xin-Lai Qian Department of Pathology The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiang Medical UniversityXinxiang 453003Henan ProvinceChina Department of Basic Medical Sciences Xinxiang Medical UniversityXinxiang 453003Henan ProvinceChina

Immune checkpoint inhibitors(ICIs)are widely used due to their effectiveness in treating various ***-related adverse events(irAEs)are defined as adverse effects resulting from ICI *** irAEs are a common type of irAEs characterized by intestinal side effects,such as diarrhea and colitis,which may lead to the discontinuation of ICIs.

关键词： Immunotherapy Immune checkpoint inhibitor Immune checkpoint inhibitor-related gastritis Immune-related adverse events Autoimmune responses

Epidermal visualized health monitoring system based on stretchable and washable TPU hybrid conductive microtextiles

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Rare Metals 2024年第7期43卷 3185-3193页

作者： Jing-Bo Yuan zhi-Hong feng Dong-Chan Li Yang Luo Yun-Lei Zhou School of Chemical Engineering Hebei University of Technology Engineering Research Center of Chemical Technology for Efficient Utilization of Seawater ResourcesMinistry of EducationTianjin 300401China National Key Laboratory of Application Specific Integrated Circuit Shijiazhuang050000China Department of Materials ETH Zürich8093 ZurichSwitzerland Hangzhou Institute of Technology Xidian UniversityHangzhou 311231China

Electronic textiles,an emerging class of electronic technology,offer exciting opportunities for seamless integration with the human *** applications have been developed based on electronic ***,researches on integrating multiple electronic textilebased devices are still *** this study,we present a system integrated with an electrocardiogram monitoring sensor and an electroluminescence device based on stretchable and washable conductive micro *** signal is acquired by an electrocardiograph amplifier and displayed by a dual-color electroluminescence device based on the processed *** integrated electronic device has excellent moisture permeability and comfort for long-term *** system reported in this study opens a new avenue for the application of electronic textiles in health monitoring,robotic prosthetics,and competitive sports.

关键词： Conductive microtextile Textile composite Electronic textile Electroluminescent displays

Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(C_(6)F_(5))_(3)/chiral phosphoric acid

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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： Zhen Liu zhi-Yuan Ren Chen Yang Xiangyi Shao Li Chen xin Li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations