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    题名 作者 年代 出处 被引量
1Geological Features and Reservoiring Mode of Shale Gas Reservoirs in Longmaxi Formation of the Jiaoshiba Area显示文摘This study is based on the sedimentation conditions, organic geochemistry, storage spaces, physical properties, lithology and gas content of the shale gas reservoirs in Longmaxi Formation of the Jiaoshiba area and the gas accumulation mode is summarized and then compared with that in northern America. The shale gas reservoirs in the Longmaxi Formation in Jiaoshiba have good geological conditions, great thickness of quality shales, high organic content, high gas content, good physical properties, suitable depth, good preservation conditions and good reservoir types. The quality shales at the bottom of the deep shelf are the main target interval for shale gas exploration and development. Shale gas in the Longmaxi Formation has undergone three main reservoiring stages:the early stage of hydrocarbon generation and compaction when shale gas reservoirs were first formed; the middle stage of deep burial and large-scale hydrocarbon generation, which caused the enrichment of reservoirs with shale gas; the late stage of uplift, erosion and fracture development when shale gas reservoirs were finally formed.GUO Xusheng HU Dongfeng LI Yuping LIU Ruobing WANG Qingbo 2014Acta Geologica Sinica(English Edition)2014,88,6:28
2Chemical weathering intensity and element migration features of the Xiashu loess profile in Zhenjiang, Jiangsu Province显示文摘在 Zhenjiang 的 Xiashu 黄土侧面的化学捱过紧张和元素迁居特征在这篇论文被学习。(1 ) Xiashu 黄土侧面经历了中等化学捱过。看起来降水是更重要的CHEN Yingyong LI Xusheng HAN Zhiyong YANG Shouye WANG Yongbo YANG Dayuan 2008Journal of Geographical Sciences2008,18,3:25
3Cobalt single atom site catalysts with ultrahigh metal loading for enhanced aerobic oxidation of ethylbenzene显示文摘The oxidation of hydrocarbons to produce high value-added compounds(ketones or alcohols)using oxygen in air as the only oxidant is an efficient synthetic strategy from both environmental and economic views.Herein,we successfully synthesized cobalt single atom site catalysts(Co SACs)with high metal loading of 23.58 wt.%supported on carbon nitride(CN),which showed excellent catalytic properties for oxidation of ethylbenzene in air.Moreover,Co SACs show a much higher turn-over frequency(19.6 h^(−1))than other reported non-noble catalysts under the same condition.Comparatively,the as-obtained nanosized or homogenous Co catalysts are inert to this reaction.Co SACs also exhibit high selectivity(97%)and stability(unchanged after five runs)in this reaction.DFT calculations reveal that Co SACs show a low energy barrier in the first elementary step and a high resistance to water,which result in the robust catalytic performance for this reaction.Yu Xiong Wenming Sun Yunhu Han Pingyu Xin Xusheng Zheng Wensheng Yan Juncai Dong Jian Zhang Dingsheng Wang Yadong Li 2021Nano Research2021,14,7:20
4Enhancing both selectivity and coking-resistance of a single-atom Pd1/C3N4 catalyst for acetylene hydrogenation显示文摘选择加氢是在化学升级的一个重要工业催化过程,在因为他们的高加氢活动,基于 Pd 的催化剂广泛地被使用的地方。然而,因为重焦炭形成,差的选择和短催化剂一生是主要担心。在这个工作,原子地驱散 Pd 原子成功地在 graphitic 碳氮化物上被综合(g-C 3 用原子层免职的 N 4) 。没有 Pd nanoparticle (NP ) ,改正错误的高角度的环形的黑暗地的扫描传播电子显微镜学(HAADF 茎) 证实了孤立的 Pd 原子的主导的存在形成。在在过量乙烯的乙炔的选择加氢期间, g-C 3 N 4-supported Pd NP 催化剂比常规 Pd/Al 2 O 3 和 Pd/SiO 2 催化剂。在原处, X 光检查光致核裂变光谱学表明可观的费用从 Pd NP 转到 g-C 3 N 4 多半在催化表演改进起一个重要作用。更给人深刻印象地,单个原子的 Pd 1/C3 N 4 催化剂展出了两种更高的乙烯选择和更高的 coking 抵抗。我们的工作证明单个原子的 Pd 催化剂是在加氢反应改进选择和焦炭抵抗的一个有希望的候选人。Xiaohui Huang Yujia Xia Yuanjie Cao Xusheng Zheng Haibin Pan Junfa Zhu Chao Ma Hengwei Wang Junjie Li Rui You Shiqiang Wei Weixin Huang Junling Lu 2017Nano Research2017,10,4:16
5Theoretical Progress and Key Technologies of Onshore Ultra-Deep Oil/Gas Exploration显示文摘Oil/gas exploration around the world has extended into deep and ultra-deep strata because it is increasingly difficult to find new large-scale oil/gas reservoirs in shallow–middle buried strata. In recent years, China has made remarkable achievements in oil/gas exploration in ultra-deep areas including carbonate and clastic reservoirs. Some (ultra) large-scale oil and gas fields have been discovered. The oil/gas accumulation mechanisms and key technologies of oil/gas reservoir exploration and development are summarized in this study in order to share China’s experiences. Ultra-deep oil/gas originates from numerous sources of hydrocarbons and multiphase charging. Liquid hydrocarbons can form in ultradeep layers due to low geothermal gradients or overpressures, and the natural gas composition in ultra-deep areas is complicated by the reactions between deep hydrocarbons, water, and rock or by the addition of mantle- or crust-sourced gases. These oils/gases are mainly stored in the original highenergy reef/shoal complexes or in sand body sediments. They usually have high original porosity. Secondary pores are often developed by dissolution, dolomitization, and fracturing in the late stage. The early pores have been preserved by retentive diageneses such as the early charging of hydrocarbons. Oil/gas accumulation in ultra-deep areas generally has the characteristics of near-source accumulation and sustained preservation. The effective exploration and development of ultra-deep oil/gas reservoirs depend on the support of key technologies. Use of the latest technologies such as seismic signal acquisition and processing, low porosity and permeability zone prediction, and gas–water identification has enabled the discovery of ultra-deep oil/gas resources. In addition, advanced technologies for drilling, completion, and oil/gas testing have ensured the effective development of these fields.Xusheng Guo Dongfeng Hu Yuping Li Jinbao Duan Xuefeng Zhang Xiaojun Fan Hua Duan Wencheng Li 2019Engineering2019,5,3:15
6Properties of Functionalized Graphene/Room Temperature Vulcanized Silicone Rubber Composites Prepared by an In-situ Reduction Method显示文摘Functionalized graphene oxide (FGO) was prepared by treating graphene oxide with γ-aminopropyl triethoxysilane (KH-550) before the mixture was dispersed into α, ω-dihydroxy polydimethylsiloxane to get room temperature vulcanized (RTV) silicone rubber composites by solution casting. The cured composites were then reduced with hydrazine hydrate to obtain functionalized graphene (FG)/RTV silicone rubber composites. The structures of FGO and the resultant composites were characterized by atomic force microscopy, FT-IR spectra and X-ray diffraction. KH-550 was found to be grafted onto graphene sheets, leading to an increased interlayer spacing. Significant improvements in thermal and mechanical properties were obtained. Both the FGO/RTV silicone rubber composite contain 1.0 wt% of FGO, and its reduced product showed an increase of one-step weight loss temperature with 61 ℃ and 133 ℃ higher than that of pure silicone rubber. Tensile strength and elongation at break of FG/RTV silicone rubber composite (with 0.5 wt% FGO content) increased by 175% and 67%, respectively, compared with those of pure silicone rubber.马文石 LI Ji DENG Bangjun LIN Xiaodan ZHAO Xusheng 2013Journal of Wuhan University of Technology(Materials Science)2013,28,1:14
7Climate and environment reconstruction during the Medieval Warm Period in Lop Nur of Xinjiang, China显示文摘We made multi-proxy analysis of 14C, grain size, microfossils, plant seeds, and geochemical elements on samples from a profile in the central West Lake of Lop Nur. The grain size suggests relatively stable sedimentary environment around the Medieval Warm Period (MWP) with weak storm effect, which is followed by frequent strong storm events. Abundant microfossils and plant seeds in this stage indicate a warm and humid fresh to brackish lake environment. C, N, and stable elements are high in content in the sediments while Rb/Sr, Ba/Sr, and Ti/Sr are in a steady low level. In addition, plenty of red willows lived here prior to about 700 a B.P., indicating a favorable environmental condition. The results indicate that the environment in Lop Nur and its west bank turned to be favorable at about 2200 a B.P., where the Loulan Culture began to thrive. Then the climate and environment came to be in the good condition in the Tang and Song Dynasties, when the storm effect became weaker, rainfall increased and the salty lake water turned to be brackish to fresh lake water. Hence, limnic biomass increased with higher species diversity.MA ChunMei WANG FuBao CAO QiongYing XIA XunCheng LI ShengFeng Li XuSheng 2008Chinese Science Bulletin2008,53,19:13
8Onset of Xiashu loess deposition in southern China by 0.9 Ma and its implications for regional aridification显示文摘The Xiashu loess is a typical Quaternary eolian deposit in southern China and represents an important terrestrial paleoclimate archive in this low-latitude monsoon region. However, the chronological framework of Xiashu loess deposition has yet to be established. Determining the timing of the onset of Xiashu loess deposition will allow researchers to better understand late Quaternary aridification across the Asian continent, the evolution of the East Asian monsoon and regional environmental changes in subtropical regions. Therefore, in this study, a systematic chronological study of the Xiashu loess is conducted to answer this question. For the first time, magnetostratigraphic classification reveals that the Matuyama/Brunhes(M/B) reversal is present in the Xiashu loess at two sites in Jiangsu Province, the Qingshan profile at Yizheng and the Dagang core in Zhenjiang.Based on the results of magnetostratigraphy and optically stimulated luminescence(OSL) dating, the age of the lower boundary of the Xiashu loess is estimated to be approximately 0.9 Ma. Consequently, this Xiashu loess deposit is the oldest reported to date and is comparable in age to the red soil deposit in Xuancheng, Anhui Province. The onset of Xiashu loess deposition by 0.9 Ma represents the further expansion of arid range in Asia in the late Quaternary in response to significant aridification and winter monsoon strengthening in this subtropical region. We suggest that these climate changes were primarily driven by global cooling and an increase in high-latitude ice volume in the Northern Hemisphere and that the initiation of Xiashu loess accumulation was a regional response of southern China to the 0.9 Ma global cooling event.Xusheng LI Zhiyong HAN Huayu LU Yingyong CHEN Yang LI Xiaokang YUAN Yuwen ZHOU Mengyao JIANG Cunjuan LV 2018Science China Earth Sciences2018,61,3:11
9Environmental change inferred from Rb and Sr of lacustrine sediments in Huangqihai Lake,Inner Mongolia显示文摘从侧面 H3 与三不同谷物尺寸部分在沉积基于 geochemical 元素 Rb 和 Sr 在上北湖河边低地在在 1986 的胡昂基海·莱克表面上面的 13 m,纸调查 palaeolakeCHEN Lei SHEN Hongyuan JIA Yulian WU Jinglu LI Xusheng WEI Ling WANG Pengling 2008Journal of Geographical Sciences2008,18,3:11
10Synthesis, mechanical investigation, and application of nitrogen and phosphorus co-doped carbon dots with a high photoluminescent quantum yield显示文摘有高 photoluminescent 量收益(PLQY ) 的做 Heteroatom 的碳点(CD ) 最近在化学传感器,光催化, bioimaging,和药交货中由于他们的应用吸引了注意。氮和磷在到在周期表的碳的靠近的最近并且是关键的在生物医学的成像的地里追踪元素。这二个元素改变 CD 的光、电子的性质并且帮助改进他们的 PLQY 的基本理解。这能也在 photoimaging 和 photothermal 治疗导致多功能的用法。然而,源于做 P 的 CD 的合成的大多数 PLQY 当前低于 50% 。这些 CD 在 bioimaging 和药交货的地里限制了实用性。在这研究,一个单个步的、高效率的热水的方法被使用综合氮和磷药的碳点((N, P ) 有有独立排放的多达 53.8% 的 PLQY 的 -CDs) 行为。而且, CD 在一个大 pH 范围上介绍了高 monodispersity,柔韧的刺激无关的光,和稳定性。分光镜的调查显示 PLQY (N, P ) CD 主要由于 P 的增加和氧化表面的钝化效果。优秀荧光性质(N, P ) CD 能被 Hg 2+ 离子有效地并且有选择地熄灭。如此的系统与一短反应时间在 0-900 nM 集中范围显示出线性回答,显示他们为化学和生物学的领域里的应用程序的潜力。Quan Xu Bofan Li Yingchun Ye Wei Cai Weijun Li Chuanyao Yang Yusheng Chen Meng Xu Neng Li Xusheng Zheng Jason Street Yan Luo Lulu Cai 2018Nano Research2018,11,7:7
11Periodical characteristics of baseflow in the source region of the Yangtze River显示文摘Baseflow,which represents the drainage of groundwater aquifers,is an essential component of runoff in hydrological basins.In the source region of the Yangtze River,the change of baseflow typically reflects the interactions between groundwater system and climatic factors in cold and arid areas.With modified Kalinen separation method,annual baseflow between 1957 and 2009 in this region was estimated and calculated.In comparison with the inner-annual variations of total streamflow,baseflow showed a weaker fluctuation.Before the 1980s,it was in a steady state;and after then,it demonstrated dramatic variations and large amplitudes.Based on the calculation results of baseflow,the real Morlet wavelet method was applied to reveal the periodical characteristics of baseflow as well as the precipitation and air temperature in the study area.It was found that annual baseflow has a 43-year trend as well as a 21-year period and a 7-year period.The 21-year period is most significant,with its wavelet coefficient having the largest fluctuation and amplitude.Summation of wavelet coefficients on these periods exhibits a similar change pattern with respect to that of annual baseflow.The summation curve takes a'W'shape,which means that the baseflow follows a four-stage sequence of descending–ascending–descending–ascending.As analyzed,the relationship among baseflow,precipitation and temperature is implied in the correlation between their normalized wavelet coefficients at different temporal scales.By the significant positive linear correlations both between precipitation and baseflow(correlation coefficient is 0.98)and between temperature and baseflow(correlation coefficient is 0.90)for the 43-year wavelet coefficients,it is suggested that the long-term increasing trends of precipitation and air temperature will lead to an increasing trend of baseflow.For wavelet coefficients of 21-year and 7-year periods,the positive linear correlation between precipitation and baseflow is significant.However,the correlation between air temperature and baseflow is not so evident,especially for the 21-year period.As a conclusion, correlation analysis with normalized wavelet coefficients showed that the change of annual baseflow was contributed mostly by the change of precipitation and secondly by the change of temperature.KaiZhu QIAN Li WAN XuSheng WANG JingJing LV SiHai LIANG 2012Journal of Arid Land2012,4,2:7
12Groundwater contributions in water-salt balances of the lakes in the Badain Jaran Desert,China显示文摘Groundwater-fed lakes are essential for the ecology in arid and semiarid regions.As a typical arid region,the Badain Jaran Desert (BJD) is famous in the world for the presence of a large number of groundwater-fed saline lakes among the mega dunes.Based on the up to date geological surveys and observations,this study analyzed the groundwater contributions in water-salt balances of the lakes in the desert.We found different types of springs,including the sublacustrine springs that indicate an upward flow of groundwater under the lakebed.A simplified water balance model was developed to analyze the seasonal variations of water level in the Sumu Barun Jaran Lake,which revealed an approximately steady groundwater discharge in the lake and explained why the amplitude of seasonal changes in lake level is less than 0.5 m.In addition,a salt balance model was developed to evaluate the salt accumulations in the groundwater-fed lakes.The relative salt accumulation time is 800–7,000 years in typical saline lakes,which were estimated from the concentration of Cl-,indicating a long history evolution for the lakes in the BJD.Further researches are recommended to provide comprehensive investigations on the interactions between the lakes and groundwater in the BJD.GONG Yanping WANG Xusheng HU B Xiao ZHOU Yangxiao HAO Chunbo WAN Li 2016Journal of Arid Land2016,8,5:7
13A naturally occurring CD8^+CD122^+ T-cell subset as a memory-like Treg family显示文摘尽管有 CD4 + CD25 + 规章的 T 房间(Tregs ) 在过去的十年期间,在他们的临床的翻译以后的进步仍然保持停滞。增长证据建议那自然地发生的 CD8 + CD122 + T 房间也是有能力的 Tregs 禁止 T 房间回答并且象 alloimmunity 一样压制 autoimmunity。事实上,他们是像记忆的 Tregs 类似于一个中央记忆 T 房间(T 厘米 ) 显型。位于他们的抑制下面的机制仍然不好被理解,尽管他们可以包括 IL-10 生产。我们最近证明了那个规划 death-1 (PD-1 ) 表达式区分在之间规章并且存储器 CD8 + CD122 + T 房间和那 CD8 + CD122 + Tregs 经历更快的 homeostatic 增长并且比常规 CD4 + CD25 + Tregs。这些调查结果可以为在诊所加速有效 Treg 治疗打开调查的一根新线。在这评论,我们在 CD8 + CD122 + Treg 在诊所研究并且讨论他们的显型,在 autoimmunity 和 alloimmunity 的镇压角色,功能的要求,行动的机制和潜在的应用。Shanshan Li Qingfeng Xie Yuqun Zeng Chuan Zou Xusheng Liu Shouhai Wu Haixia Deng Yang Xu Xian C Li Zhenhua Dai 2014Cellular & Molecular Immunology2014,11,4:6
14Probiotic effect of ferulic acid esterase-producing Lactobacillus plantarum inoculated alfalfa silage on digestion,antioxidant,and immunity status of lactating dairy goats显示文摘A feeding experiment was conducted to determine the effects of inoculating alfalfa silage with a ferulic acid esterase-producing inoculum on feed digestibility,rumen fermentation,antioxidant,and immunity status of lactating dairy goats.Twenty dairy goats were distributed into 2 experimental groups consisting of control diet(Lp MTD/1,including Lactobacillus plantarum MTD/1 inoculated silage)against diet containing silage treated with ferulic acid esterase-producing L.plantarum A1(Lp A1).Alfalfa silage inoculated with a ferulic acid esterase-producing Lp A1 had better fermentation quality than the Lp MTD/1inoculation.The application of Lp A1 improved silage antioxidant capacity as indicated by greater total antioxidant capacity(T-AOC),superoxide dismutase(SOD)and glutathion peroxidase(GSH-Px)activities in Lp A1 treated silage versus Lp MTD/1 treatment.Compared with Lp MTD/1 treated group,inoculation of silage with Lp A1 increased apparent total tract digestibility of dietary dry matter,organic matter and crude protein,and ruminal concentrations of total volatile fatty acids,acetate,propionate and isobutyrate as well.The results of current study also demonstrated improved antioxidant capacity and immune performance of dairy goats with Lp A1 inoculation.Feeding Lp A1-treated silage increased dairy goats’serum antioxidase activity,such as T-AOC,SOD,GSH-Px and catalase,and the serum concentration of immunoglobulin A,while decreased tumor necrosis factor a,interleukin(IL)-2 and IL-6.In addition,compared with Lp MTD/1,diet containing alfalfa silage inoculated with Lp A1 endowed dairy goats’milk with greater fat and protein contents,improved dairy goat milk quality without affecting feed efficiency.Fuhou Li Baibing Zhang Yixin Zhang Xia Zhang Samaila Usman Zitong Ding Lizhuang Hao Xusheng Guo 2022Animal Nutrition2022,,4:6
15In situ trapped high-density single metal atoms within graphene: Iron-containing hybrids as representatives for efficient oxygen reduction显示文摘因为他们为特殊催化作用的效率和 chemoselectivity 比传统的催化剂的那些优异,原子地驱散的催化剂在精力变换应用吸引了注意。然而,他们在支持上由于极其低的装载金属的内容有限制,在在高温度的金属地点和数量以及低稳定性的精确控制的困难。我们经由葡萄糖, dicyandiamide,和无机的金属盐的单个步的热热分解准备了一个高度做的单个金属原子混血儿。高角度的环形的黑暗扫描地的传播电子显微镜学(HAADF 茎) 和 X 光检查吸收罚款结构光谱学(XAFS ) 表明做进 graphene 矩阵的氮原子为由产生 metal-Nx 协作结构的金属原子稳定是枢轴的。由于 graphene 矩阵的强壮的抛锚效果,装载内容的金属是在孤立的原子混血儿的超过 4 wt.%( 磅内容象在做磅的混血儿的 9.26 wt.% 一样高) 。而且,单个做铁的混血儿(做 Fe@N 的 graphene ) 为氧减小反应显示出显著 electrocatalytic 表演。山峰力量密度是 199Daobin Liu Chuanqiang Wu Shuangming Chen Shiqing Ding Yaofeng Xie Changda Wang Tao Wang Yasir A. Haleem Zia ur Rehman Yuan Sang Qin Liu Xusheng Zheng Yu Wang Binghui Ge Hangxun Xu Li Song 2018Nano Research2018,11,4:6
16Effect of biodiesel on the particle size distribution in the exhaust of common-rail diesel engine and the mechanism of nanoparticle formation显示文摘Effect of biodiesel blends on the particle size distribution (PSD) of exhaust aerosol and the mechanism of nanoparticle formation were investigated with a modern common rail light-duty diesel engine. The results showed that PSD of diesel included two modes:nucleation mode (NM) and accumulation mode (CM). The criterion diameter of the two modes is 50 nm. Only CM was observed for all fuels under the condition of 50 N.m,2000 r/min. When the engine torque was higher than 150 N.m,log-modal PSD of diesel shifted to bimodal. At higher loads,if the biodiesel blend ratio was below 60%,the PSD of biodiesel blends still included the two modes. However,no NM particles were found for pure biodiesel. At lower loads,only CM was found in PSD of all fuels. Significant reduction of CM particles was found for biodiesel blends compared with diesel. Discussion on the mechanism of nanoparticle formation indicated that for the light-duty diesel engine with oxidation catalysts,fuel consumption and exhaust temperature increased with increasing the engine loads,and SO2 was converted to SO3 by catalyst which,in its hydrated form,could act as the precursor for biodiesel NM formation. Therefore,sulfur level of biodiesel blends dominates the nanoparticle formation in light-duty diesel engine with oxidation catalysts.ZHANG XuSheng ZHAO Hui HU ZongJie WU ZhiJun LI LiGuang 2009Science China(Technological Sciences)2009,52,9:5
17Surface curvature-confined strategy to ultrasmall nickel-molybdenum sulfide nanoflakes for highly efficient deep hydrodesulfurization显示文摘Size-controlled synthesis of two-dimensional(2D)catalysts with low stacking numbers and small nanoflake lengths is crucial for promoting the catalytic performance in diverse heterogeneous catalysis.Herein,we report a facile and general“surface curvature-confined synthesis”strategy to modulate the slab lengths and stacking numbers of 2D transition metal sulfides by controlling the strain induced by different surface curvature of supports.An efficient NiMo sulfide with shorter slab length(average 3.71 nm),less stacking number(1–2 layers)and more edge active sites is synthesized onto ZSM-5 zeolites with the average size of 100 nm,which shows superior kHDS value of dibenzothiophene(14.05×10^−7 mol/(g·s)),enhanced stability up to 80 h,and high direct desulfurization selectivity(>95%).This design concept is also proved to be generally applicable to modulate the slab lengths and stacking numbers of other 2D catalysts such as MoS2 and WS2 nanoflakes,which shows great potentials for developing more ultrasmall 2D catalysts with controlled sizes and excellent catalytic activities.Xin Kang Jiancong Liu Chungui Tian Dongxu Wang Yaorui Li Hongyan Zhang Xusheng Cheng Aiping Wu Honggang Fu 2020Nano Research2020,13,3:5
18Effect of Bacillus amyloliquefaciens and Bacillus subtilis on fermentation, dynamics of bacterial community and their functional shifts of whole-plant corn silage显示文摘Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during ensiling.If the BA and BS inoculants have positive effects on silages,then they could not only improve fermentation characteristics,but also deliver BA or BS viable cells to ruminants,which would play its probiotic effect.Therefore,the objectives of this study were to investigate the effects of BA and BS on the fermentation,chemical characteristics,bacterial community and their metabolic pathway of whole-plant corn silage.Results:Freshly chopped whole-plant corn was inoculated without or with BA and BS,respectively,and ensiled for1,3,7,14 and 60 d.Results showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control,and BA inoculation decreased acetic acid concentrations,whereas BS inoculation decreased fiber contents and increased crude protein(CP)content.Higher water-soluble carbohydrate contents and lower starch contents were observed in BA-and BS-inoculated silages compared with that in control.The decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage,which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated silage.In addition,it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins,and decreased the relative abundances of drug resistance:antimicrobial pathways.We also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present study.There were no significant differences in bacterial community compositions among the three groups during ensiling.However,BA and BS inoculations decreased the relative abundances of undesirable bacteria such as Acetobacter and Acinetobacter.Conclusion:Our findings suggested that the BS strain was more suitable as silage inoculants than the BA strain in whole-plant corn silage in this study.Jie Bai Marcia Franco Zitong Ding Lin Hao Wencan Ke Musen Wang Dongmei Xie Ziqian Li Yixin Zhang Lin Ai Xusheng Guo 2022Journal of Animal Science and Biotechnology2022,13,3:5
19Permeability Heterogeneity in a Fractured Sandstone-Mudstone Rock Mass in Xiaolangdi Dam Site,Central China显示文摘Heterogeneity of permeability in fractured media is a hot research topic in hydrogeology. Numerous approaches have been proposed to characterize heterogeneity in the last several decades. However,little attention has been paid to correlate permeability heterogeneity with geological information.In the present study,several causes of permeability heterogeneity,that is,lithology, tectonism,and depth,are identified.The unit absorption values(denoted asω),which are results obtained from the packer test,are employed to represent permeability.The variability of permeability in sandstone-mudstone is so significant that the value of unit absorptions span 3-4 orders of magnitude at any depth with several test sections.By declustering,it has been found that under a similar tectonic history,the means of permeability differ greatly at different formations as a result of different mudrock contents.It has also been found that in the same formation,permeability can be significantly increased as a result of faulting.The well-known phenomenon,the decrease in permeability with depth,is found to be caused by the fractures in the rock mass,and the relationship between permeability and depth can be established in the form of logω-logd.After subtracting the trend ofωwith absolute depth,the mean of the residual value at each relative depth can be well correlated with the distribution of mudstone. The methods proposed in this paper can be utilized to research in similar study areas.JIANG Xiaowei WAN Li WANG Xusheng KANG Aibin HUANG Jun HUANG Guoxing 2009Acta Geologica Sinica(English Edition)2009,83,5:4
20An Overview of Bearing Candidates for the Next Generation of Reusable Liquid Rocket Turbopumps显示文摘There is a consensus in the aerospace field that the development of reusable liquid rockets can effectively reduce the launch expense.The pursuit of a long service life and reutilization highly depends on the bearing components.However,the rolling element bearings(REBs)used in the existing rocket turbopumps present obvious and increasing limitations due to their mechanical contacting mode.For REBs,high rotational speed and long service life are two performance indexes that mutually restrict each other.To go beyond the DN value(the product of the bearing bore and rotational speed)limit of REBs,the major space powers have conducted substantial explorations on the use of new types of bearings to replace the REB.This review discusses,first,the crucial role of bearings in rocket turbopumps and the related structural improvements of REBs.Then,with the prospect of application to the next generation of reusable liquid rocket turbopumps,the bearing candidates investigated by major space powers are summarized comprehensively.These promising alternatives to REBs include fluid-film,foil,and magnetic bearings,together with the novel superconducting compound bearings recently proposed by our team.Our more than ten years of relevant research on fluid-film and magnetic bearings are also introduced.This review is meaningful for the development of long-life and highly reliable bearings to be used in future reusable rocket turbopumps.Jimin Xu Changhuan Li Xusheng Miao Cuiping Zhang Xiaoyang Yuan 2020Chinese Journal of Mechanical Engineering2020,33,2:4
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