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Cr-catalyzed allylic C(sp^(3))–H addition to aldehydes enabled by photoinduced ligand-to-metal charge transfer

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Science China Chemistry 2024年第5期67卷 1589-1595页

作者： Xianrong Zeng Feng-Hua Zhang Runchen lai Xiaoyu Lin Zhaobin Wang Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Instrumentation and Service Center for Molecular SciencesWestlake UniversityHangzhou 310024China

Photoinduced ligand-to-metal charge transfer(LMCT) has emerged as an effective strategy for synthesizing organic molecules in a sustainable manner. However, the majority of existing reports on selective C(sp^(3))–H bond functionalization via photoinduced LMCT focus on the use of late transition metals or rare-earth metals for radical additions or cross-couplings. In contrast, the utilization of photoinduced LMCT with 3d early transition metals poses a significant challenge. Herein, we describe an unprecedented approach to allylic C(sp^(3))–H addition to aldehydes, employing chromium(Cr) complexes as catalysts through visible-light-induced LMCT. By investigating the reaction pathway through various mechanistic studies, including radical trapping, kinetic isotope effect(KIE) analysis, and transient absorption spectroscopy, valuable insights have been gained. The proposed mechanism suggests the intermediacy of bromine radicals through homolysis of the Cr–Br bond. Notably, this protocol expands our understanding of the photochemical properties of earth-abundant Cr complexes.

关键词： Cr catalysis photoinduced ligand-to-metal charge transfer hydrogen-atom transfer carbonyl addition

Primary hyperparathyroidism-induced acute pancreatitis in pregnancy:A systematic review with a diagnostic-treatment algorithm

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World Journal of Gastroenterology 2024年第32期30卷 3755-3765页

作者： Goran Augustin Quirino lai Maja Cigrovski Berkovic Department of Surgery University Hospital Centre Zagreb and School of Medicine University of ZagrebZagreb 10000Croatia General Surgery and Organ Transplantation Unit Department of SurgerySapienza University of RomeRome 00018Italy Department for Sport and Exercise Medicine Faculty of KinesiologyUniversity of ZagrebZagreb 10000Croatia

BACKGROUND Primary hyperparathyroidism(PHPT)-induced acute pancreatitis(AP)during pregnancy has rarely been *** to this rarity,there are no diagnostic or treatment algorithms for pregnant *** To determine appropriate diagnostic methods,therapeutic options,and factors related to maternal and fetal outcomes for PHPT-induced AP in *** A literature search of articles in English,Japanese,German,Spanish,and Italian was performed using PubMed(1946-2023),PubMed Central(1900-2023),and Google *** Preferred Reporting Items for Systematic reviews and Meta-Analyses(PRISMA)protocol was *** search terms included“pancreatite acuta,”“iperparatiroidismo primario,”“gravidanza,”“travaglio,”“puerperio,”“postpartum,”“akute pankreatitis,”“primärer hyperparathyreoidismus,”“Schwangerschaft,”“Wehen,”“Wochenbett,”“pancreatitis aguda,”“hiperparatiroidismo primario,”“embarazo,”“parto,”“puerperio,”“posparto,”“acute pancreatitis,”“primary hyperparathyroidism,”“pregnancy,”“labor,”“puerperium,”and“postpartum.”Additional studies were identified by reviewing the reference lists of retrieved ***,imaging,surgical,obstetric,and outcome data were *** Fifty-four cases were collected from the 51 *** median maternal age was 29 ***-induced AP starts at the 20th gestational week;higher gestational weeks were seen in mothers who died(mean gestational week 28).Median values of amylase(1399,Q1-Q3=519-2072),lipase(2072,Q1-Q3=893-2804),serum calcium(3.5,Q1-Q3=3.1-3.9),and parathormone(PTH)(384,Q1-Q3=123-910)were *** 46 cases,adenoma was the cause of PHPT,followed by 2 cases of carcinoma and 1 case of *** the remaining 5 cases,the diagnosis was not *** ultrasound was positive in 34 cases,whereas sestamibi was performed in 3 cases,and neck computed tomography or magnetic resonance imaging was performed in 9 cases(the enlarged parathyroid gland was not localized in 3 cases).Surgery was the prefer

关键词： Primary hyperparathyroidism Acute pancreatitis Pregnancy Diagnosis Maternal mortality Fetal mortality Algorithm

带蒂中鼻甲黏膜瓣在鼻内镜修复脑脊液鼻漏手术中的应用

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临床耳鼻咽喉头颈外科杂志 2021年第9期35卷 833-836页

作者：来育斌何星辰王剑许敏陈晓栋中国人民解放军空军军医大学第一附属医院耳鼻咽喉头颈外科西安710032

目的:探讨带蒂中鼻甲黏膜瓣在经鼻内镜修复脑脊液鼻漏手术中的应用及疗效。方法:回顾分析15例脑脊液鼻漏患者,其中单纯脑脊液鼻漏13例(86.7%),脑脊液鼻漏伴脑膜脑膨出2例(13.3%)。术中根据瘘口位置采用经鼻内镜下带蒂中鼻甲黏膜瓣进行修... 详细信息

目的:探讨带蒂中鼻甲黏膜瓣在经鼻内镜修复脑脊液鼻漏手术中的应用及疗效。方法:回顾分析15例脑脊液鼻漏患者,其中单纯脑脊液鼻漏13例(86.7%),脑脊液鼻漏伴脑膜脑膨出2例(13.3%)。术中根据瘘口位置采用经鼻内镜下带蒂中鼻甲黏膜瓣进行修复,其中漏口位于筛顶5例(33.3%),漏口位于筛板8例(53.3%),漏口位于蝶窦外侧隐窝2例(13.3%)。结果:术后随访4~24个月,手术成功率为100%,术区黏膜上皮化良好,未出现脑脊液鼻漏复发及其他并发症。结论:带蒂中鼻甲黏膜瓣修复脑脊液鼻漏手术成功率高,鼻腔损伤小,值得临床推广。

关键词：脑脊液鼻漏中鼻甲内镜外科手术

Dynamical distribution of continuous service time model involving non-Maxwellian collision kernel and value functions

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Chinese Physics B 2024年第9期33卷 340-348页

作者： Minfang Zhao Lingting Kong Miao Liu Shaoyong lai School of Mathematics and Statistics Yili Normal UniversityYining 835000China Institute of Applied Mathematics Yili Normal UniversityYining 835000China School of Mathematics Southwestern University of Finance and EconomicsChengdu 611130China

The distribution of continuous service time in call centers is investigated.A non-Maxwellian collision kernel combining two different value functions in the interaction rule are used to describe the evolution of continuous service time,*** the statistical mechanical and asymptotic limit methods,Fokker–Planck equations are derived from the corresponding Boltzmann-type equations with non-Maxwellian collision *** steady-state solutions of the Fokker–Planck equation are obtained in exact *** experiments are provided to support our results under different parameters.

关键词： kinetic theory service time Fokker–Planck equation value function

Highly reversible Zn anode enabled by anticatalytic carbon layer with suppressed hydrogen evolution

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Rare Metals 2024年第7期43卷 3044-3054页

作者： Wen-Duo Zhang Chuang Sun Yu-Xuan Zhu Feng Gao Chao lai School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou221116China

Aqueous zinc-ion batteries(AZIBs)have emerged as a promising high-efficiency energy storage system due to the high energy density,low-cost and environmental ***,the practical application of AZIBs is severely restricted by the challenges faced by the Zn anode,which include uncontrollable dendrite growth,corrosion and hydrogen evolution ***,a simple and convenient physical vapor deposition(PVD)method is reported for fabricating uniform graphite as a protection layer on the surface of Zn *** high conductivity graphite layer on Zn anode(denoted as Zn@C)not only benefits the uniform distribution of the electric field,but also provides numerous Zn nucleation sites to regulate and navigate Zn-ion stripping/plating ***,the graphite layer with a poor catalytic activity endows the Zn@C anode with a highly suppressed hydrogen ***,a hydrogen and dendrite free anode is achieved with artificial anticatalytic carbon layer on Zn anode,exhibiting a high reversibility and excellent cycling stability over 2600 h at the current density of 5 mA·cm^(-2)with a capacity of 2.5 mAh·cm^(-2)and longtime cycling stability for assembled full *** work strategically designs the properties of the artificial interface layer to effectively address various challenges simultaneously,which presents insights for the future development of high-performance rechargeable AZIBs.

关键词： Zn metal anode Artificial anticatalytic layer Hydrogen suppression Dendrite free

Oils with different degree of saturation:effects on ileal digestibility of fat and corresponding additivity and bacterial community in growing pigs

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1657-1668页

作者： Lu Wang Yifan Chen Yuansen Yang Nuo Xiao Changhua lai State Key Laboratory of Animal Nutrition Ministry of Agriculture and Rural Affairs Feed Industry CentreChina Agricultural UniversityNo.2 Yuanmingyuan West RoadHaidian DistrictBeijing 100193China College of Animal Science and Technology Hebei Agricultural UniversityHebei 071000China

Background Oils are important sources of energy in pig *** combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of oil *** experiment was conducted to evaluate the effects of oils with different degree of saturation on the fat digestibility and corresponding additivity and bacterial community in growing *** Eighteen crossbred(Duroc×Landrace×Yorkshire)barrows(initial body weight:29.3±2.8 kg)were surgically fitted with a T-cannula in the distal *** experimental diets included a fat-free basal diet and 5 oil-added *** 5 oil-added diets were formulated by adding 6%oil with different ratio of unsaturated to saturated fatty acids(U:S)to the basal *** 5 oils were palm oil(U:S=1.2),canola oil(U:S=12.0),and palm oil and canola oil were mixed in different proportions to prepare a combination of U:S of 2.5,3.5 and 4.5,*** The apparent and standardized ileal digestibility(AID and SID)of fat and fatty acids increased linearly(P<0.05)as the U:S of dietary oils increased except for SID of fat and C18:*** AID and SID of fat and fatty acids differed among the dietary treatments(P<0.05)except for SID of unsaturated fatty acids(UFA)and C18:*** one-slope broken-line analyses for the SID of fat,saturated fatty acids(SFA)and UFA indicated that the breakpoint for U:S of oil was 4.14(R^(2)=0.89,P<0.01),2.91(R^(2)=0.98,P<0.01)and 3.84(R^(2)=0.85,P<0.01),*** determined SID of fat,C18:1,C18:2 and UFA in the mixtures was not different from the calculated SID of fat,C18:1,C18:2 and ***,the determined SID of C16:0,C18:0 and SFA in the mixtures were greater than the calculated SID values(P<0.05).The abundance of Romboutsia and Turicibacter in pigs fed diet containing palm oil was greater than that in rapeseed oil treatment group,and the two bacteria were negatively correlated with SID of C16:0,C18:0 and SFA(P<0.05).

关键词： Additivity Bacterial community Fat and fatty acids Growing pigs Ratio of unsaturated to saturated fatty acids Standardized ileal digestibility

On the role of sliding friction effect in nonlinear tri-hybrid vibration-based energy harvesting

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1295-1314页

作者： Jiamei WANG Siukai lai Chen WANG Yiting ZHANG Zhaolin CHEN Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina The Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057Guangdong ProvinceChina Hebei Key Laboratory of Mechanical Reliability for Heavy Equipments and Large Structures Yanshan UniversityQinghuangdao 066000Hebei ProvinceChina School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

This work aims to develop an experimental investigation into the effectiveness of the sliding-mode approach for hybrid vibration-based energy harvesting.A proposed sliding-mode triboelectric-electromagnetic-piezoelectric energy harvesting model involves a cantilever beam with a tip mass exposed to magnetic and frictional *** experimental findings indicate that the system can achieve its peak inter-well oscillation output within a low-frequency range of 4 Hz–6 *** has a lesser impact on the open-circuit voltage output at an excitation acceleration of 1.5g compared with *** distribution of tri-stability changes with the presence of *** model provides a deeper understanding of the influence of the dry friction coefficient(0.2–0.5) on the interactive behaviors of different generator units.

关键词： sliding mode tri-hybrid energy harvesting friction nonlinear behavior

Tetrathiafulvalene esters with high redox potentials and improved solubilities for non-aqueous redox flow battery applications

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Green Energy & Environment 2024年第5期9卷 899-908页

作者： Weikang Hu Jiaqi Xu Nanjie Chen Zongcai Deng Yuekun lai Dongyang Chen College of Materials Science and Engineering Fuzhou UniversityFuzhou350116China College of Chemical Engineering Fuzhou UniversityFuzhou350116China

The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxﬂow ***,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are *** has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester *** battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a speciﬁc capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V ***/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF *** excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory ***,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxﬂow batteries.

关键词： Non-aqueous redox flow batteries Tetrathiofulvarene Redox potential Solubility Substituent effect

Tribological Behaviors of Electroless Nickel-Boron Coating on Titanium Alloy Surface

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 309-320页

作者： Yao Jia Jianping lai Jiaxin Yu Huimin Qi Yafeng Zhang Hongtu He Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education State Key Laboratory of Environment-Friendly Energy MaterialsSouthwest University of Science and TechnologyMianyang 621010China

Titanium alloys are excellent structural materials in engineering fields,but their poor tribological properties limit their further *** plating is an effective method to enhance the tribological performance of alloys,but it is difficult to efficiently apply to titanium alloys,due to titanium alloy’s strong chemical *** this work,the electroless Nickel-Boron(Ni-B)coating was successfully deposited on the surface of titanium alloy(Ti-6AL-4V)via a new pre-treatment ***,linearly reciprocating sliding wear tests were performed to evaluate the tribological behaviors of titanium alloy and its electroless Ni-B *** was found that the Ni-B coatings can decrease the wear rate of the titanium alloy from 19.89×10^(−3)mm^(3)to 0.41×10^(−3)mm^(3),which attributes to the much higher hardness of Ni-B *** heat treatment,the hardness of Ni-B coating further increases corresponding to coating crystallization and hard phase ***,heat treatment does not improve the tribological performance of Ni-B coating,due to the fact that higher brittleness and more severe oxidative wear exacerbate the damage of heat-treated ***,the Ni-B coatings heat-treated both in air and nitrogen almost present the same tribological *** finding of this work on electroless coating would further extend the practical applications of titanium alloys in the engineering fields.

关键词： Electroless coating Titanium alloy Tribology Wear Heat treatment Nanoindentation