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Solvothermal Synthesis and Crystal Structure of Zn(en)_3B_5O_7(OH)_3

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Chemical Research in Chinese Universities 2006年第3期22卷 271-273页

作者： HE Yi chen wei yang Jin XI Chun-yu chen Jie-sheng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

A new polyborate containing ehiral metal-complex Zn（en）3 B5O7（OH）3, where en = ethylenediamine, was synthesizedunder solvothermal conditions and structurally characterized by means of X-ray diffraction analysis. Crystal data： Zn（en）3 B5O7（OH）3, monoclinic, space group P21/c, a =0.8532（72） nm, b =2.3340（5） nm, c = 0.9526（92） nm, β =107. 04（3）°, Z=4, V=1.8140（6） nm^3, Dc =1.694 g/cm^3, p=1.416 mm^-1, F（000） = 960, GOF = 1. 020, R =0. 0276, Rw =0. 0828. There is a chiral Zn（en）3^2＋ complex cation and an isolated B5O7（OH）3^2- group in a Zn（en）3 B5O7（OH）3 molecule. The enantiomer of the chiral complex cation is separated orderly as ,4 and A configurations in the compound and the borate group consists of two B303 cycles linked through a bridging boron atom.

关键词： Solvothermal synthesis Crystal structure Chiral metal-complex Borate compound

Genome-wide transcriptional analysis of maize endosperm in response to ae wx double mutations

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Journal of Genetics and Genomics 2010年第11期37卷 749-762页

作者： Xiang Li Guang Hui chen wei yang Zhang Xiansheng Zhang State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Taian 271018 China

Starch biosynthesis is important during endosperm development. Much has been known for the regulation of gene expression involved in starch synthesis, less information is available on the genome-wide expression profiles as a consequence of impaired starch synthesis. In this study, we examined the transcriptional responses through microarray analysis in an ae wx double-mutant with loss-of-function starch branching enzyme IIb （SBEIIb） and granule-bound starch synthase I （GBSSI）. Through Gene Ontology enrichment analysis, we identified differentially expressed genes （DEGs） involved in chromatin organization and lipid transport. The DEGs also include alcohol dehydrogenase genes and pyruvate decarboxylase genes involved in sugar metabolism. In summary, the ae wx double mutations caused pleiotropic effects and transcriptional changes for a number of genes involved in metabolism, cellular response and organization. Therefore, a block in starch synthesis triggers transcriptional responses to favour the flux of excess carbohydrates into glycolysis, pentose phosphate pathway, and cell wall biosynthesis, but not toward the synthesis of alternative storage compounds.

关键词： transcriptional regulation starch biosynthesis carbohydrate metabolism

Long-term results of small-diameter proximal splenorenal venous shunt:A retrospective study

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World Journal of Gastroenterology 2011年第29期17卷 3453-3458页

作者： Hao chen wei-Ping yang Ji-Qi Yan Qin-Yu Li Di Ma Hong-wei Li Department of Surgery Ruijin HospitalShanghai Jiaotong University School of MedicineShanghai 200025China

AIM:To investigate recurrent variceal hemorrhage and long-term survival rates of patients treated with partial proximal splenorenal venous ***:Patients with variceal hemorrhage who were treated with small-diameter proximal splenorenal venous shunt in Ruijin Hospital between 1996 and 2009 were included in this *** diameter was determined before operation using Duplex Doppler ***-operative and long-term results in term of rehemorrhage,encephalopathy and mortality were followed ***:Ninety-eight patients with Child A and B variceal hemorrhage received small-diameter proximal splenorenal venous shunt with a diameter of 7-10 *** operation,the patients’mean free portal pressure (P<0.01)and the flow rate of main portal vein(P< 0.01)decreased significantly compared with that before *** rates of rebleeding and mortality were 6.12%(6 cases)and 2.04%(2 cases),***-one patients were followed up for 7 mo-14 years (median,48.57 mo).Long-term rates of rehemorrhage and encephalopathy were 4.40%(4 cases)and 3.30% (3 cases),*** patients(14.29%)died mainly due to progressive hepatic *** ten-year survival rates were 82.12%and 71.24%,***:Small-diameter proximal splenorenal venous shunt affords protection against variceal rehemorrhage with a low occurrence of encephalopathy in patients with normal liver function.

关键词： Partial portacaval shunt Hemorrhage Esophageal varices Shunt diameter Encephalopathy

Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1241-1248页

作者： chen Li Wenhui Ma yang Li Kuixian wei Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical *** involves systematic and theoretical engineering technology for utilizing planetary resources in ***,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the *** this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil *** microstructural characteristics of the lunar soil may drastically change its metallurgical *** main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral *** nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar *** ions injected by solar wind may promote the hydrogen reduction *** widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar ***,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar *** is a property that earth samples and tradi-tional simulated lunar soil *** application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil.

关键词： space metallurgy Chang’e-5 lunar soil space weathering metallurgical performance

On optimal streaming kernelization algorithms

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Science China(Information Sciences) 2024年第8期67卷 337-338页

作者： Hao FENG wei yang Jianer chen School of Computer Science Guangzhou University Department of Computer Science and Engineering Texas A&M University

The streaming model has been a popular model in big data computation. Streaming kernelization algorithms can be regarded as data compression processes on streaming data. In this study, we give a general method for developing computational lower bounds for streaming kernelization algorithms that is applicable to a large class of computational problems. As an example, we use the method to prove computational lower bounds for the well-known problem d-Hi TTin GSET.

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The relation between modes of lithologic association and interlayer-gliding structures in coal mine

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Journal of Coal Science & Engineering(China) 2010年第1期16卷 47-52页

作者： LE Qi-lang chen Ping yang wei-min School of Earth Sciences and Environmental Engineering Anhui University of Science and Technology Huainan 232001 China

As a case study of the Panji No.1 Coal Mine in Anhui Province, based on thesite measured and statistical data, summarized the lithologic associations, characteristicsand distribution laws of interlayer-gliding structures and tectonic coal in the No.11-2 *** results show that 9 modes of lithologic association can form *** is more easy for rock slip to occur when the lithologic associations are mainroof + coal seam + immediate floor type, compound roof+immediate roof + coal seam +immediate floor type and immediate roof + coal seam + immediate floor *** of roof and floor are the precondition to the formation of interlayer-glidingstructures.

关键词： coal seam roof and floor modes of lithologic association interlayer-gliding structure Panji No.1 Coal Mine

Discovery of six high-redshift quasars with the Lijiang 2.4 m telescope and the Multiple Mirror Telescope

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Research in Astronomy and Astrophysics 2012年第9期12卷 1185-1190页

作者： Xue-Bing Wu Wen-Wen Zuo Qian yang wei-Min Yi chen-wei yang Wen-Juan Liu Peng Jiang Xin-Wen Shu Hong-Yan Zhou Department of Astronomy Peking University Beijing 100871 China wuxb @*** National Astronomical Observatories / Yunnan Astronomical Observatory Chinese Academy ofSciences Kunming 650011 China Key Laboratory for Research in Galaxies and Cosmology The University of Science andTechnology of China Chinese Academy of Sciences Hefei 230026 China Polar Research Institute of China Shanghai 200136 China

Quasars with redshifts greater than 4 are rare, and can be used to probe the structure and evolution of the early universe. Here we report the discovery of six new quasars with i-band magnitudes brighter than 19.5 and redshifts between 2.4 and 4.6 from spectroscopy with the Yunnan Faint Object Spectrograph and Camera (YFOSC) at the Lijiang 2.4 m telescope in February, 2012. These quasars are in the list of z > 3.6 quasar candidates selected by using our proposed J K/i Y criterion and the photometric redshift estimations from the SDSS optical and UKIDSS near-IR photometric data. Nine candidates were observed by YFOSC, and five among six new quasars were identified as z > 3.6 quasars. One of the other three objects was identified as a star and the other two were unidentified due to the lower signal-to-noise ratio of their spectra. This is the first time that z > 4 quasars have been discovered using a telescope in China. Thanks to the Chinese Telescope Access Program (TAP), the redshift of 4.6 for one of these quasars was confirmed by the Multiple Mirror Telescope (MMT) Red Channel spectroscopy. The continuum and emission line properties of these six quasars, as well as their central black hole masses and Eddington ratios, were obtained.

关键词： quasars: general — quasars: emission lines — galaxies: active — galax- ies: high-redshift

Design of low-frequency circular metastructure isolators with high-load-bearing capacity

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Chinese Journal of Aeronautics 2024年第10期37卷 207-220页

作者： Ning chen Zhichun yang Te yang Yizhou SHEN wei TIAN Yanlong XU School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China National Key Laboratory of Strength and Structural Integrity Xi’an 710065China State Key Laboratory for Strength and Vibration of Mechanical Structures Xi’an 710049China

Traditional vibration isolation structures cannot work effectively for low-frequency vibration under heavy loads,due to the inherent contradiction between the high-static and lowdynamic stiffness of these *** the challenge can be effectively addressed by introducing a negative stiffness mechanism,the existing structures inevitably have complex ***,a class of man-made structures with both extraordinary mechanical properties and simple configurations,provide a new insight for low-frequency vibration isolation *** this paper,circular metastructure isolators consisting of some simple beams are designed for low-frequency vibration,including a single-layer isolator and a double-layer isolator,and their static and dynamic characteristics are studied,*** the static characteristic,the force–displacement and stiffness–displacement curves are obtained by finite element simulation;for the dynamic characteristic,the vibration transmissibility curves are obtained analytically and *** result shows that the circular nonlinear single-layer isolator has excellent lowfrequency isolation performance,and the isolation frequency band will decrease about 20 Hz when the isolated mass is fixed at 1.535 kg,compared with a similar circular linear *** static and dynamic properties are well verified through *** work provides an innovative approach for the low-frequency vibration isolation and has wide potential applications in aeronautics.

关键词： Isolator Low-frequency Curved beam Metastructure Stiffness

Prediction of maximum upward displacement of shield tunnel linings during construction using particle swarm optimization-random forest algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 1-17页

作者： Xiaowei YE Xiaolong ZHANG Yanbo chen Yujun wei yang DING MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou310058China Department of Civil Engineering Zhejiang UniversityHangzhou310058China Zhejiang Engineering Research Center of Intelligent Urban Infrastructure Hangzhou City UniversityHangzhou310015China

During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield *** floating will increase the initial stress on the segments and bolts which is harmful to the service performance of the *** this study we used a random forest(RF)algorithm combined particle swarm optimization(PSO)and 5-fold cross-validation(5-fold CV)to predict the maximum upward displacement of tunnel linings induced by shield tunnel *** mechanism and factors causing upward movement of the tunnel lining are comprehensively *** input variables were selected according to results from analysis of influencing *** prediction performance of two models,PSO-RF and RF(default)were *** Gini value was obtained to represent the relative importance of the influencing factors to the upward displacement of *** PSO-RF model successfully predicted the maximum upward displacement of the tunnel linings with a low error(mean absolute error(MAE)=4.04 mm,root mean square error(RMSE)=5.67 mm)and high correlation(R^(2)=0.915).The thrust and depth of the tunnel were the most important factors in the prediction model influencing the upward displacement of the tunnel linings.

关键词： Random forest(RF) Particle swarm optimization(PSO) Upward displacement of lining Machine learning prediction Shieldtunneling construction