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Guadalupian(Middle Permian)δ^13Corg changes in the Lower Yangtze,South China

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Acta Geochimica 2020年第6期39卷 988-1001页

作者： Hengye wei Ziao Geng xuan Zhang School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China School of Earth Science East China University of TechnologyNanchang 330013China

The Middle Permian Guadalupian witnessed significant environmental changes in the Phanerozoic such as large-scale sea-level drop,supercontinent Pangaea assembly,and transition from Early Permian glaciation to Late Permian non-glacial *** tracers can provide insights for these environmental ***δ^13C studies of the entire Guadalupian epoch are rare,and most of them has focused on near the end of Guadalupian and carb on isotopes of ino ***,we present carbon isotopic compositions of organic matters in the Guadalupian from two sections(Chaohu and Xiaolao)in the Lower Yangtze *** *** results show that 313Corg profiles in the Guadalupian show a peak in the Roadian and a gradual negative shift from the Roadian to the middle *** trends can be matched by(δ^13C changes of carbonate rocks or organic matter in South China and other places in the world,representi ng a global carb on cycle *** Roadian positive peak was probably due to high productivity which was caused by upwelling during cooling *** gradual negative shift of(δ^13C was caused mainly by a decrease of organic matter burial on land and in the ocean,resulting from global sea-level drop and anoxia-caused benthos decline,*** less important causes for the gradualδ^13C negative shift are volcanic-gases releasing,decreased mountain belts,and the resultant reduced silicate weathering-consumption of *** gradual negative shift ofδ^13C coincides with the gradual extinction in the ***,global sea-level drop and marine reducing conditions may be the main causes of the gradual extinction in the Guadalupian.

关键词： Organic-carbon isotope Carbon cycle Mass extinction Kuhfeng Formation Chaohu Xiaolao

The incidence and predictors of high-degree atrioventricular block in patients with bicuspid aortic valve receiving selfexpandable transcatheter aortic valve implantation

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Journal of Geriatric Cardiology 2021年第10期18卷 825-835页

作者： Yuan-weixiang OU jing-jing HE xuan ZHOU Guo-Yong LI Yan-Biao LIAO Xin wei Yong PENG Yuan FENG Mao CHEN Department of Cardiac Catheterization Laboratory West China HospitalSichuan UniversitySichuanChina Department of Cardiology West China HospitalSichuan UniversitySichuanChina Department of Radiology West China HospitalSichuan UniversitySichuanChina

BACKGROUND The high-degree atrioventricular block(HAVB)in patients with bicuspid aortic valve(BAV)treated with transcatheter aortic valve implantation(TAVI)remains *** study aims to explore this poorly understood subject of mech-anisms and predictors for HAVB in BAV self-expandable TAVI *** We retrospectively included 181 BAV patients for *** computed tomography data,the curvature of ascending aorta(AAo)was quantified by the angle(AAo angle)between annulus and the cross-section at 35 mm above annulus(where the stent interacts with AAo the most).The valvular anatomy and leaflet calcification were also *** The 30-day HAVB rate was 16.0%(median time to HAVB was three days).Type-1 morphology was found in 79 pat-ients(43.6%)(left-and right-coronary cusps fusion comprised 79.7%).Besides implantation below membrane septum,large AAo angle[odds ratio(OR)=1.08,P=0.016]and type-1 morphology(OR=4.97,P=0.001)were found as the independent predictors for *** with baseline right bundle branch block,these predictors showed strong predictability for HAVB with area under the cure of 0.84(sensitivity=62.1%,specificity=92.8%).Bent AAo and calcified raphe had a synergistic effect in facilita-ting high implantation,though the former is associated with at-risk deployment(device implanted above annulus+prothesis pop-out,versus straight AAo:9.9%vs.2.2%,P=0.031).CONCLUSIONS AAo curvature and type-1 morphology are novel predictors for HAVB in BAV patients following self-expandable *** patients with bent AAo or calcified raphe,a progressive approach to implant the device above the lower edge of membrane septum is favored,though should be done cautiously to avoid pop-out.

关键词： patients anatomy implantation

Higher alcohols synthesis from syngas over lanthanum-promoted CuZnAl catalyst

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Journal of Energy Chemistry 2018年第1期27卷 319-325页

作者： xuan Deng Yong-Jun Liu wei Huang Key Laboratory of Coal Sdence and Technology of Ministry of Education and Shanxi Province Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Center of Information Management and Development Taiyuan University of TechnologyTaiyuan 030024ShanxiChina

CuZnAl catalysts with different La loadings were prepared by a complete liquid phase method and tested for higher alcohols（C_（2＋）OH） synthesis from syngas at the conditions of 250–290 ℃, 4.5 MPa, feed low rate = 150 mL/min and H_2/CO = 2. The catalysts were characterized by XRD, H_2-TPR, NH_3-TPD, N_2 adsorption, XPS, and TEM techniques. Characterization results showed that the incorporation of La into CuZnAl catalysts resulted in the decrease of crystallite size of Cu^0 and a strong interaction among copper and zinc or aluminum oxides. Especially, the incorporation of La increased the amount of weak acid and the Cu content on catalyst surface, which was speculated to contribute the formation of higher alcohols. Among these La-promoted CuZnAl catalysts, the La0.1 catalyst exhibited the best catalytic performance and the selectivity to higher alcohols reached above 60% when the reaction temperature was 290 ℃.

关键词： Syngas C2+OH CuZnAl La promoter Slurry bed reactor

The population structure and sex ratios of Bursaphelenchus xylophilus under a-pinene stress

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Journal of Forestry Research 2020年第3期31卷 921-926页

作者： jing Cui Yong-Xia Li wei Zhang xuan Wang Long Pan Yu-Qian Feng Xing-Yao Zhang Research Institute of Forestry New Technology Chinese Academy of ForestryBeijing 100091People’s Republic of China Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing 210037People’s Republic of China

Pine wood nematode(PWN), Bursaphelenchus xylophilus, is a serious pathogen of pines throughout the world. Previous work indicated that different concentrations of a-pinene could affect nematode reproduction,however the mechanism of that influence is not clear. In order to examine the reproductive strategies of PWN in response to the stress of the volatile material a-pinene, we investigated different aspects of population changes of *** under two concentrations of a-pinene. The results show that a high concentration(214.5 mg ml-1)promoted population growth while a low concentration(56.33 mg ml-1) decreased the population. Population structure was analyzed and it was found that a high concentration of a-pinene decreased the percentage of adults but increased the percentages of larvae and ***, from the results of an evaluation of sex ratios(female/male), it was determined that a high concentration could elevate sex ratios but a low concentration decreased ratios sharply. These results suggest that the PWN could regulate its population by changing sex ratios under stress of a-pinene. This study has provided a theoretical basis for the prevention and control of pine wilt disease caused by the pine wood nematode.

关键词： Pine wood nematode α-Pinene Population structure Sex ratios

Intrinsic polarization coupling in 2Dα‐In_(2)Se_(3)toward artificial synapse with multimode operations

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SmartMat 2021年第1期2卷 88-98页

作者： jing Gao Yue Zheng wei Yu Yanan Wang Tengyu Jin xuan Pan Kian Ping Loh wei Chen Department of Physics National University of SingaporeSingaporeSingapore Department of Chemistry National University of SingaporeSingaporeSingapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhouChina National University of Singapore(Suzhou)Research Institute SuzhouChina

Emulation of advanced synaptic functions of the human brain with electronic devices contributes an important step toward constructing high‐efficiency neuromorphic *** materials are promising candidates as synaptic weight elements in neural network hardware due to their controllable polarization ***,the increased depolarization field at the na-noscale and the complex fabrication process of the traditional ferroelectric materials hamper the development of high‐density,low‐power,and highly sensitive synaptic ***,we report the implementation of two‐dimensional(2D)ferroelectricα‐In_(2)Se_(3)as an active channel material to emulate typical synaptic ***α‐In_(2)Se_(3)‐based synaptic device fea-tures multimode operations,enabled by the coupled ferroelectric polarization under various voltage pulses applied at both drain and gate ***,the energy consumption can be reduced to~1 pJ by using high‐κdielectric(Al2O3).The successful control of ferroelectric polarizations inα‐In_(2)Se_(3)and its application in artificial synapses are expected to inspire the implementation of 2D ferroelectric materials for future neuromorphic systems.

关键词： 2D ferroelectrics artificial synapse high‐κdielectric multimode operations α‐In_(2)Se_(3)

Stabilization of Cu/ZnO Based Catalysts by Nickel Additive in Methanol Decomposition

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Chemical Research in Chinese Universities 2001年第4期17卷 420-425页

作者： XI jing-yu WANG Zhi-fei LU Gong-xuan State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsThe Chinese Academy of SciencesLanzhou 730000P.R.China

A series of Cu/Zn based catalysts with and without Ni, prepared by the co-precipitation method, has been studied for methanol decomposition. CO and H2 are the major products. The Cu/Zn catalysts show a low initial activity and a poor stability. The formation of the CuZn alloys was observed in the deactivated Cu/Zn catalysts which were used for methanol decomposition at 250 . When small amounts of Ni were added in the catalyst, the Cu/Zn/Ni(molar ratio 5/4/ x) catalysts showed a high activity at a low temperature. The activity and the stability of the catalyst depend on the nickel content. The activity of the Cu/Zn/Ni catalysts was maintained at a. relatively stable value of 78% conversion of methanol with 95% selectivity of H2, 93% selectivity of CO, and a more than 70% yield of hydrogen was obtained at 250 C when x >1. The stability of the Cu/Zn/Ni (molar ratio 5/4/x) catalysts showed the maximum (ca 88%) when x=1. The stabilization effect of nickel on the Cu/Zn based catalysts may lead to the increasing of the dispersion of active Cu species and the prevention of CuZn alloys formation.

关键词： Nickel Cu/Zn catalysts Stabilization Methanol Decomposition

A mechanically robust egg white hydrogel scaffold with excellent biocompatibility by three-step green processing

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Science China(Technological Sciences) 2022年第7期65卷 1599-1612页

作者： wei Zhen-Zhen DONG xuan ZHANG Yu-Qing School of Biology and Basic Medical Sciences Medical CollegeSoochow UniversitySuzhou 215123China College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

Egg white(EW) is one of the most common and high-quality nutritional proteins. A novel three-step green processing technology is constructed to process homogeneous EW into a mechanically robust EW hydrogel scaffold(EWHS) with excellent biocompatibility. The homogeneous EW is first treated with stream to form a hydrogel, then slowly dehydrated to form a fragile and almost transparent EW glass, and finally annealed into an EWHS. The EWHS is water-insoluble, wet soft and translucent and has a porous network structure, and its pore size distribution is between 0.1–1.0 μm. The tensile strength in wet state is as high as 5.0 MPa, the elongation at break is about 93%, and the swelling rate is about 85%. The order of the enzymatically residual rate of these EWHSs is pepsin > neutral protease > papain> trypsin > alkaline protease. Mouse L929 cells can adhere,proliferate, and grow well on the EWHSs. After EWHS was implanted in rats for three weeks, the levels of IL-6, TNF-α, and NF-κB inflammatory factors did not change significantly in comparison with the pseudo-operated and normal groups. This novel EW hydrogel biomaterial has potential applications in medical 3 D tissue engineering materials, such as tendons, soft tissues, and in vivo implants.

关键词： egg white hydrogel scaffolds dehydration heat treatment mechanical properties swelling rate

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Synthesis and Anti-HIV Activity of Triazolo-fused 3 ＇,4＇-Cyclic and 4＇-Spiro Nucleoside Analogues

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Chemical Research in Chinese Universities 2013年第3期29卷 473-476页

作者： SUN jing-bo LIU Rong-wang xuan Li-li LENG wei-chun WU Jin-chang College of Chemistry Jilin University Changchun 130012 P. R. China China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China

Triazolo-fused 3＇,4＇-cyclic nucleoside 4＇-spiro nucleoside analogues were synthesized by an intramolecular 1,3-dipolar cycloaddition of 4＇-azido nucleoside derived azido-alkynes in a regio- and stereo-specific manner. The thy- mine nucleoside base in these target compounds was transformed into the corresponding 5-methyl cytosine component. The synthesized compounds were examined in an MAGI（multinuclear-activation galactosidase indicator） assay for exploring the anti-HIV activity and in a H9 T（human T lymphocytes Hg） assay for measuring the cell toxicity.

关键词： 4'-Spiro nucleoside 3',4'-fused nucleoside Biological activity 1,3-Dipolar cycloaddition

Chinese Word Segmentation via BiLSTM+Semi-CRF with Relay Node

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Journal of Computer Science & Technology 2020年第5期35卷 1115-1126页

作者： Nuo Qun Hang Yan Xi-Peng Qiu xuan-jing Huang School of Computer Science Fudan UniversityShanghai 200433China Shanghai Key Laboratory of Intelligent Information

Semi-Markov conditional random fields(Semi-CRFs)have been successfully utilized in many segmentation problems,including Chinese word segmentation(CWS).The advantage of Semi-CRF lies in its inherent ability to exploit properties of segments instead of individual elements of *** its theoretical advantage,Semi-CRF is still not the best choice for CWS because its computation complexity is quadratic to the sentenced *** this paper,we propose a simple yet effective framework to help Semi-CRF achieve comparable performance with CRF-based models under similar computation ***,we first adopt a bi-directional long short-term memory(BiLSTM)on character level to model the context information,and then use simple but effective fusion layer to represent the segment ***,to model arbitrarily long segments within linear time complexity,we also propose a new model named *** direct modeling of segments makes the combination with word features easy and the CWS performance can be enhanced merely by adding publicly available pre-trained word *** on four popular CWS datasets show the effectiveness of our proposed *** source codes and pre-trained embeddings of this paper are available on https://***/fastnlp/fastNLP/.

关键词： Semi-Markov conditional random field(Semi-CRF) Chinese word segmentation bi-directional long short-term memory deep learning