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N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： yi Zhang Hui cai Xiuhai Gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

Interplay between Microscopic Structures and Macroscopic Viscoelastic Properties of Polyampholyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1360-1367,I0008页

作者： You-cai Xue yi-Ming Yang Di Jia Beijing National Laboratory for Molecular Sciences Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

Polyampholyte gels,which have hierarchical structures,exhibit excellent self-healing properties and have great promise for biomaterials and *** investigated the relationship between microscopic structures and macroscopic viscoelastic properties of polyampholyte gels and found three factors influencing their viscoelastic properties,including the chemical crosslinking bonds,topological entanglements controlled by monomer concentration,and the ionic *** strength plays a major role on the strength of ionic bonds.A crossover point of elastic modulus and loss modulus was observed in the dynamic frequency sweeps at low monomer concentration or low chemical crosslinking density for gels with intermediate strength of ionic *** solid-liquid transition signaled by the crossover point is a typical feature of dynamic associated gels,representing the dynamical association-dissociation of the ionic bonds and full relaxation of the topological entanglements in the gel *** the crossover point disappears when the ionic bonds are too weak or too strong to form“permanent”***,in the non-linear yielding measurement,gels with intermediate strength of the ionic bonds are ductile and yield at very large shear strain due to the self-healing properties and the dynamic association-dissociation of the ionic *** the self-healing properties disappear when the ionic bond strength is too weak or too *** work reveals the mechanism of how the dynamic association-dissociation of ionic bonds influences both the linear and non-linear viscoelastic properties of the polyampholyte gels.

关键词： Polyampholyte gel Ionic bond Topological entanglement Self-healing Hierarchical structure

Heterogeneous engineering of MnSe@NC@ReS_(2) core-shell nanowires for advanced sodium-/potassium-ion batteries

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Rare Metals 2024年第8期43卷 3713-3723页

作者： Sheng-Jun Lu Jin-yi Lin cai-Hong Wang Yu-Fei Zhang yi Zhang Hao-Sen Fan College of Materials Science and Metallurgy Engineering Guizhou University Guiyang 550025China School of Energy Science and Engineering Nanjing Tech UniversityNanjing 211816China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China

Sodium-ion batteries(SIBs) and potassium-ion batteries(PIBs) have been attracting great attentions and widely been exploited due to the abundant sodium/potassium ***,the preparation of high-powered anode materials for SIBs/PIBs plays a decisive role for the commercial applications of SIBs/PIBs in the *** selenides are a class of potential anode materials for SIBs/PIBs because of their small band gap and high electrical *** this work,MnSe and ReS_(2) core-shell nanowires connecting by polydopamine derived carbon nanotube(MnSe@NC@ReS_(2)) have been successfully synthesized from growing ReS_(2) nanosheets array on the surface of MnSe@NC nano wires,which present excellent Na^(+)/K^(+) storage *** applied as SIBs anode,the specific capacity of 3.0 mAh·g^(-1) was maintwined after 400 cycles at the current density of 1.0 A·g^(-1).Besides,it could also keep 120 mAh·g^(-1) specific capacity after 900 cycles at 1.0 A·g^(-1) for the anode of *** heterogeneous engineering and one-dimensional-two-dimensional(1D-2D) hybrid strategies could provide an ideal strategy for the synthesis of new hetero-structured anode materials with outstanding battery performance for SIBs and PIBs.

关键词： Heterogeneous engineering Core-shell nanowires MnSe@NC@ReS_(2)nanowires Na^(+)batteries K^(+)batteries

Visualisation and Heat Transfer Performance of Mini-Channel Flat Heat Pipe with a Binary Mixture

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Journal of Thermal Science 2024年第5期33卷 1712-1725页

作者： FAN Gaoting TANG Aikun cai Tao SHAN Chunxian PAN Jun JIN yi School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China Jiangsu Jinhe Energy Technology Co.Ltd Zhenjiang 212400China

To unravel the intricacies of two-phase gas-liquid flow characteristics and heat transfer behavior,an array mini-channel gravity plate heat pipe(AMGPHP)is proposed in this work,which allows for observing the internal changes in the state of the working *** flow patterns such as pool flow,columnar flow,and slug flow,are experimentally explored and analyzed in *** is found that the optimal volume fill ratio is 20%by utilizing start-up time and thermal resistance as performance evaluation *** this fill ratio,a medium optimization strategy by blending ethanol within R141b is proposed and *** comparison to pure working fluids,the heat transfer performance of AMGFHP in the binary fluid has been significantly augmented due to temperature and concentration shifts resulting from disparate boiling *** the 10%volume fraction ethanol blending condition,the equivalent thermal conductivity of the heat pipe is dramatically elevated,with a value of 3.10 W/(m·℃),along with the reduction of the minimum start-up power to 4 *** general,applying such a medium to heat pipes has considerable potential in practical applications.

关键词： flat heat pipe mini-channel visualisation two-phase flow binary mixtures thermal performance

Different lymph node staging systems for predicting the prognosis of colorectal neuroendocrine neoplasms

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1745-1755页

作者： Yuan-yi Zhang Yue-Wei cai Xia Zhang Department of Pathology Zhaoqing Medical CollegeZhaoqing 526020Guangdong ProvinceChina Department of Emergency Zhaoqing Second People’s HospitalZhaoqing 526020Guangdong ProvinceChina Department of Pathology and Physiology Zhaoqing Medical CollegeZhaoqing 526020Guangdong ProvinceChina

BACKGROUND Colorectal neuroendocrine neoplasms(NENs)are a rare malignancy that primarily arises from the diffuse distribution of neuroendocrine cells in the colon and *** studies have pointed out that the status of lymph node may be used to predict the *** To investigate the predictive values of lymph node ratio(LNR),positive lymph node(PLN),and log odds of PLNs(LODDS)staging systems on the prognosis of colorectal NENs treated surgically,and compare their predictive *** This cohort study included 895 patients with colorectal NENs treated surgically from the Surveillance,Epidemiology,and End Results *** endpoint was mortality of patients with colorectal NENs treated surgically.X-tile software was utilized to identify most suitable thresholds for categorizing the LNR,PLN,and *** were selected in a random manner to form training and testing *** prognosis of surgically treating colorectal NENs was examined using multivariate cox analysis to assess the associations of LNR,PLN,and LODDS with the prognosis of colorectal NENs.C-index was used for assessing the predictive *** conducted a subgroup analysis to explore the different lymph node staging systems’predictive *** After adjusting all confounding factors,PLN,LNR and LODDS staging systems were linked with mortality in patients with colorectal NENs treated surgically(P3.,4-,5-and 6-year follow-up *** LNR,PLN,and LODDS were found to significantly predict the prognosis of patients with colorectal NENs treated surgically.

关键词： Positive lymph node Lymph node ratio Log odds of positive lymph nodes Prognosis Colorectal neuroendocrine neoplasms

Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 139-146页

作者： Guan-Wen Yuan Lei Lei Yuan-Zhu Wang Bo Wang yi-ying Wang Chao Chen Zhao-Qiang Shen yi-Fu {3. yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope(JWST),which were unexpected to form at such an early time within the standard Big Bang *** this work,we propose that this puzzle can be explained by the presence of some primordial black holes(PBHs)with a mass of~1000M_(⊙).These PBHs act as seeds for early galaxy formation with masses of~10^(8)-10^(10)M_(⊙)at high redshift,hence accounting for the JWST *** use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models,and find that the Lognormal model with the M_(c)~750M_(⊙)is preferred over other *** rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects,similar to those recently discovered by *** we focused on PBHs in this work,the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

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Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study

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Food Science and Human Wellness 2024年第1期13卷 254-264页

作者： Huijuan Ruan Yajie Zhang Qingya Tang Xuan Zhao Xuelin Zhao yi Xiang Wei Geng yi Feng Wei cai Department of Clinical Nutrition Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition Shanghai Institute of Pediatric ResearchShanghai 200092China Department of Pediatric Surgery Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China

Objective:Postpartum weight retention(PPWR)is a common problem among women after *** main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and ***:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(3. mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary *** the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body *** body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and ***:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)*** 12-17 months postpartum,the PPWR was(0.98±4.06)*** was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months *** addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in *** leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any *** results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or ***:Breastfeeding mothers may retain considerable weight gai

关键词： Human milk Milk composition Body weight Body mass index(BMI) Weight gain Postpartum weight retention

FSS: algorithm and neural network accelerator for style transfer

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Science China(Information Sciences) 2024年第2期67卷 253-266页

作者： yi LING Yujie HUANG Yujie cai Zhaojie LI Mingyu WANG Wenhong LI Xiaoyang ZENG State Key Laboratory of ASIC & System Fudan University Shanghai Explore X Technology Co. Ltd.

Neural networks(NNs), owing to their impressive performance, have gradually begun to dominate multimedia processing. For resource-constrained and energy-sensitive mobile devices, an efficient NN accelerator is necessary. Style transfer is an important multimedia application. However, existing arbitrary style transfer networks are complex and not well supported by current NN accelerators, limiting their application on mobile devices. Moreover, the quality of style transfer needs improvement. Thus, we design the Fast Style system(FSS), where a novel algorithm and an NN accelerator are proposed for style transfer. In FSS, we first propose a novel arbitrary style transfer algorithm, Fast Style. We propose a light network that contributes to high quality and low computational complexity and a prior mechanism to avoid retraining when the style changes. Then, we redesign an NN accelerator for Fast Style by applying two improvements to the basic NVIDIA deep learning accelerator(NVDLA) architecture. First, a flexible dat FSM and wt FSM are redesigned to enable the original data path to perform other operations(including the GRAM operation)by software programming. Moreover, statistics and judgment logic are designed to utilize the continuity of a video stream and remove the data dependency in the instance normalization, which improves the accelerator performance by 18.6%. The experimental results demonstrate that the proposed Fast Style can achieve higher quality with a lower computational cost, making it more suitable for mobile devices. The proposed NN accelerator is implemented on the Xilinx VCU118 FPGA under a 180-MHz clock. Experimental results show that the accelerator can stylize 512×512-pixel video with 20 FPS, and the measured performance reaches up to 3.6.07 GOPS. The ASIC implementation in TSMC 28 nm achieves about 22 FPS in the case of a 720-p video.

关键词： neural network accelerator style transfer neural network deep learning

Well-controlled Organocatalytic Ring-opening Polymerization of Seven-membered Cyclic Carbonates with Cyclohexyl Fusion

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CHEMICAL RESEARCH IN CHINESE UNIVERSITIES 2024年第5期40卷 856-862页

作者： Zhang, Wei Shan, Si-yi Dai, Jiang cai, Zhongzheng Zhu, Jian-Bo Tianjin Univ Sci & Technol Coll Chem Engn & Mat Sci Tianjin Key Lab Brine Chem Engn & Resource Ecoutil Tianjin 300457 Peoples R China Sichuan Univ Coll Chem Natl Engn Lab Ecofriendly Polymer Mat Sichuan Chengdu 610064 Peoples R China

Developing green and well-controlled polymerization methods is of great significance for the preparation of biomedical polymer materials. In this contribution, an efficient organocatalytic ring-opening polymerization (ROP) of a class of seven-membered cyclic carbonates (T6DO, T6HDO, C6DO, C6HDO) containing cis- or trans-cyclohexane structure was established. Organic catalyst 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) promoted living polymerization of these cyclic carbonates to deliver polycarbonate and block copolymer products with predictable molecular weights and narrow dispersity. The robust TBD-mediated ROP at 90 degrees C showcased turnover frequency (TOF) up to 10(3. h(-1). The resulting amorphous polycarbonates displayed good thermal stability.

关键词： CO2 Organic catalyst Living ring-opening polymerization Aliphatic polycarbonate KINETIC RESOLUTION POLYMERIZATION RAC-LACTIDE