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Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： Yu-Mei Wang Mei-Xia Tao Kai-Ming Mo xu Chen shu-Hua Zhong Elena S shubina Guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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Systemic autoimmune abnormalities complicated by cytomegalovirus-induced hemophagocytic lymphohistiocytosis:A case report

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World Journal of Clinical Cases 2020年第20期8卷 4946-4952页

作者： shu-xian Miao Zhi-Qi Wu Hua-Guo xu Department of Laboratory Medicine The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina

BACKGROUND Hemophagocytic lymphohistiocytosis(HLH)is a rare but life-threatening disorder,characterized by a hyperimmune *** mortality is high despite progress being made in the diagnosis and treatment of the *** is traditionally divided into primary(familial or genetic)and secondary(reactive)according to the *** HLH(sHLH),more common in adults,is often associated with underlying conditions including severe infections,malignancies,autoimmune diseases,or other *** SUMMARY The case involves a 31-year-old woman,presented with a high persistent fever,rash,and *** met the diagnostic criteria of the HLH-2004 guideline and thus was diagnosed with HLH,with positive anti-nuclear antibody(ANA)and positive cytomegalovirus(CMV)-*** patient responded well to a combination of immunomodulatory,chemotherapy,and supportive *** her PCR evaluation for CMV turned negative,her serum ferritin also dropped *** clinical symptoms improved dramatically,and except for ANA,the abnormal laboratory findings associated with HLH returned to *** previous study has shown that the median overall survival of HLH patients is only 6 mo;however,our patient has been cured and has not presented with any relapse of the disease for 6 *** This case emphasizes that thorough early removal of the CMV infection is significant for the prognosis of this HLH patient.

关键词： Hemophagocytic lymphohistiocytosis Autoimmune abnormalities Cytomegalovirus Anti-nuclear antibody Serum ferritin Case report

Field-Free Molecular Orientation Induced by Nonresonant Square Laser Pulses

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Chinese Physics Letters 2011年第4期28卷 83-86页

作者： xu shu-Wu HUANG Yun-Xia JI xian-Ming School of Science Nantong UniversityNantong 226007

We propose a scheme to achieve field-free molecular orientation by a nonresonant square laser *** CO molecules as an example,we show that,differing from the conventional Gaussian pulse,field-free molecular orientation excited by square pulses can be realized in both nonadiabatic and adiabatic *** also show that the maximum degree of the molecular orientation can be further enhanced by separating one square pulse into two time delayed subpulses and by applying the second subpulse at the beginning of the rotational wave packet rephrasing created by the first subpulse and the optimal intensity ratio between the two subpulses is about I_(1)/I_(2)=1:1.5.

关键词： pulse separating Pulse

ZnO Additive Boosts Charging Speed and Cycling Stability of Electrolytic Zn–Mn Batteries

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Nano-Micro Letters 2024年第4期16卷 293-304页

作者： Jin Wu Yang Tang Haohang xu Guandie Ma Jinhong Jiang Changpeng xian Maowen xu shu‑Juan Bao Hao Chen Institute for Clean Energy&Advanced Materials School of Materials and EnergySouthwest UniversityChongqing 400715People’s Republic of China

Electrolytic aqueous zinc-manganese(Zn–Mn) batteries have the advantage of high discharge voltage and high capacity due to two-electron reactions. However, the pitfall of electrolytic Zn–Mn batteries is the sluggish deposition reaction kinetics of manganese oxide during the charge process and short cycle life. We show that, incorporating ZnO electrolyte additive can form a neutral and highly viscous gel-like electrolyte and render a new form of electrolytic Zn–Mn batteries with significantly improved charging capabilities. Specifically, the ZnO gel-like electrolyte activates the zinc sulfate hydroxide hydrate assisted Mn^(2+) deposition reaction and induces phase and structure change of the deposited manganese oxide(Zn_(2)Mn_(3)O_8·H_(2)O nanorods array), resulting in a significant enhancement of the charge capability and discharge efficiency. The charge capacity increases to 2.5 mAh cm^(-2) after 1 h constant-voltage charging at 2.0 V vs. Zn/Zn^(2+), and the capacity can retain for up to 2000 cycles with negligible attenuation. This research lays the foundation for the advancement of electrolytic Zn–Mn batteries with enhanced charging capability.

关键词： Electrolytic aqueous zinc-manganese batteries Electrolyte pH value ZnO electrolyte additive Fast constant-voltage charging ability

Highly Cis-1,4 Selective Polymerization of Conjugated Dienes Catalyzed by ^-heterocyclic Carbene-ligated Neodymium Complexes

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Chinese Journal of Polymer Science 2020年第12期38卷 1305-1312页

作者： shu Zhang Na Wu Yi-xian Wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Neodymium complexes containing N heterocyclic carbene(NHC)ligands,NdCl5[1,3,R(NCH=)2C]-THF,(Nd1:R=2,6-Pr2C6H3,x=0;Nd2:R=2,6-Et2C6H3,x=1;Nd3:R=2.4,6-Me3C6H2,x=1)were synthesized and employed as precatalysts for the coordination polymerization of conjugated dienes(butadiene and isoprene).In combination with trisobutylaluminium(TIBA),Nd1 promoted butadiene polymerization to produce extremely high cis-1,4(up to 99.0%)polybutadienes with high molecular weight(Mw=250-780 kg·mol 1).The Nd1/TIBA catalytic system also exhibited both high catalytic activity and cis-1,4 selectivity(up to 97.8%)for isoprene *** catalytic activity,molecular weight and molecular weight distribution of resulting polydienes were directly influenced by Al/Nd molar ratio,aging method,and polymerization *** interestingly,the high cis-1,4 selectivity of the catalyst towards butadiene and isoprene kept almost unchanged under different reaction *** cis-1,4 polyisoprenes with high molecular weight(Mw=210-530 kg·mol 1)and narrow molecular weight distribution (Mw/Mn=1.9-2.7)as well as high cis-1.4 selectivity(-~97%)could be synthesized by using the aged Nd1/TIBA catalytic system in the presence of isoprene(100 equivalent to Nd)at low AlNd molar ratios of *** with low molecular weights(Mw=12-76 kg·mol-7)and narrow molecular weight distributions (Mw/Mn=1.7-2.6)were obtained by using Nd2 and Nd3 as precatalysts,indicating that the molecular weight of resulting polyisoprenes can be adjusted by changing the substitutes of ligand in Nd complex.

关键词： Neodymium complex N heterocydic carbene igand Coordination polymerization Cis-14 sletivity Aging method

Exact solutions of non-Hermitian chains with asymmetric long-range hopping under specific boundary conditions

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Chinese Physics B 2022年第1期31卷 81-86页

作者： Cui-xian Guo shu Chen Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Yangtze River Delta Physics Research Center Liyang 213300China

We study the one-dimensional general non-Hermitian models with asymmetric long-range hopping and explore how to analytically solve the systems under some specific boundary *** the introduction of long-range hopping terms prevents us from finding analytical solutions for arbitrary boundary parameters,we identify the existence of exact solutions when the boundary parameters fulfill some constraint relations,which give the specific boundary *** analytical results show that the wave functions take simple forms and are independent of hopping range,while the eigenvalue spectra display rich model-dependent ***,we find the existence of a special point coined as pseudo-periodic boundary condition,for which the eigenvalues are the same as those of the periodical system when the hopping parameters fulfill certain conditions,whereas the eigenstates display the non-Hermitian skin effect.

关键词： non-Hermitian physics exact solution topological physics long-range hopping

Langmuir-Blodgett Films of C_(60)-end-capped Poly(ethylene oxide)

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Chinese Journal of Polymer Science 2019年第6期37卷 604-608页

作者： Ke Ou xian xu Yu Shao Wei-Jie Wang Wen-Bin Zhang shu-Guang Yang Center for Advanced Low-dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Material Science and Engineering Donghua University Key Laboratory of Polymer Chemistry&Physics of Ministry of Education Center for Soft Matter Science and Engineering College of Chemistry and Molecular Engineering Peking University

Buckyballs(C_(60)) are linked to one end and two ends of linear poly(ethylene oxide)(PEO) chains through highly efficient click chemistry to obtain giant amphiphilic molecules C_(60)-PEO and C_(60)-PEO-C_(60), respectively. C_(60)-PEO and C_(60)-PEO-C_(60) molecules are spread on water surface and then transferred to solid substrates with Langmuir-Blodgett(LB) film deposition approach. C_(60)-PEO and C_(60)-PEO-C_(60) exhibit fractal growth behavior on the solid substrate under certain conditions owing to the crystallization ability of PEO segment. PEO chain length and the end capped mode both affect the fractal growth pattern.

关键词： LB film Giant amphiphilic molecule Fractal growth

Enhanced thermal- and impact-initiated reactions of PTFE/Al energetic materials through ultrasonic-assisted core-shell construction

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Defence Technology（防务技术） 2022年第8期18卷 1362-1368页

作者： Zhou-yang Wu Jin-xu Liu Song Zhang xian-qing Liu Xiao xu Wei-zhe Ma shu-kui Li Chuan He School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Science and Technology on Transient Impact Laboratory No.208 Research Institute of China Ordnance Industries102202China Department of Materials Science and Engineering Shenzhen MSU-BIT UniversityShenzhen518172China

A facile and economical approach was developed for the large-scale production of powdered core-shell structured PTFE/Al (CS-PA) energetic materials through ultrasonic-assisted mixing. The low-cost micrometer-sized PTFE and Al particles were used as starting materials. Under high-power ultrasonic waves, the PTFE powder was dispersed into nano-to sub-micrometer-sized particles and then encapsulated the Al microparticles to form the core-shell structure. The heat of combustion, burning rate, and pressurization rate of the powdered CS-PA were measured. The thermal-initiated reaction behavior was further evaluated using thermogravimetry-differential scanning calorimetry. Subsequently, the bulk CS-PA with a uniform microstructure was obtained via cold isostatic pressing of the powdered CS-PA followed by vacuum sintering. For the bulk CS-PA, the quasi-static compression behavior was characterized, and the impact-initiated reaction processes were conducted using the Split Hopkinson Pressure Bar (SHPB) and evaluated by a high-speed camera. Compared to physically mixed PTFE/Al materials, the powdered and bulk CS-PA demonstrated enhanced thermal- and impact-initiated reaction characteristics respectively, proving the effectiveness of our approach for constructing core-shell structures.

关键词： PTFE/Al Core-shell structure Energetic materials Ultrasonic-assisted mixing

Considerations of treatment standardization from the procession of NCCN guideline of esophagealcancer

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Chinese Journal of Cancer 2010年第10期29卷 860-864页

作者： xian-shu Gao Department of Radiation Oncology Peking University First Hospital Beijing 100034 P. R. China

Esophageal carcinoma is one of the most common malignant tumors, especially in China which is the high incidence area. As a result of mild symptoms of early-stage esophageal cancer, the majority of patients cannot be diagnosed until they develop to advanced cancer, and the treatment outcome of surgery or chemoradiotherapy is still unsatisfactory at present. The guidelines of esophageal cancer issued by National Comprehensive Cancer Network (NCCN) are regarded as important reference tools by clinical oncologists, and provide uniform criteria for the diagnosis and treatment of esophageal carcinoma. However, the guidelines are not always suitable for Chinese patients because the data come from European and American population which have significant ethnical difference from Chinese. We retrospectively analyzed the changes of treatment strategy of esophageal cancer in NCCN guidelines and the advance of treatment for esophageal carcinoma in China, aiming to provide our oncologists with new research ideas. We also hope to set up clinical cancer cooperation organizations, and release our own cancer guidelines to serve Chinese patients and oncologists.

关键词：治疗效果食管癌标准化癌症患者恶性肿瘤民族差异合作组织肿瘤学