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Community Dynamics of Seed Rain in Mixed Evergreen Broad-leaved and Deciduous Forests in a Subtropical Mountain of Central China

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Journal of Integrative Plant Biology 2007年第9期49卷 1294-1303页

作者： ze-Hao Shen yuan-yuan Tang Nan Lü Jun Zhao Dao-Xing Li Gong-Fang wang Department of Ecology College of Environmental Sciences the Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 China National Dalaoling Forest Park Yichang 435000 China

Seed dispersal is a key process within community dynamics. The spatial and temporal variations of seed dispersal and the interspecific differences are crucial for understanding species coexistence and community dynamics. This might also hold for the mixed evergreen broadleaved and deciduous forests in the mountains of subtropical China, but until now little existing knowledge is available for this question. In 2001, we chose to monitor the seed rain process of our mixed evergreen broad-leaved and deciduous forest communities in Mount Dalaoling National Forest Park, Yichang, Hubei Province, China. The preliminary analyses show obvious variations in seed rain density, species compositions and timing of seed rain among four communities. The average seed rain densities of the four communities are 2.43 ± 5.15, 54.13 ±182.75, 10.05 ±19.30 and 24.91 ± 58.86 inds/m^2, respectively; about one tenth the values in other studies in subtropical forests of China. in each community, the seed production is dominated by a limited number of species, and the contributions from the others are generally minor. Fecundity of evergreen broadleaved tree species is weaker than deciduous species. The seed rain of four communities begins earlier than September, and stops before December, peaking from early September to late October. The beginning date, ending date and peak times of seed rain are extensively varied among the species, indicating different types of dispersal strategies. According to the existing data, the timing of seed rain is not determined by the climate conditions in the same period, while the density of seed rain may be affected by the disturbances of weather variations at a finer temporal resolution.

关键词： interspecific difference Mount Dalaoling mountain mixed evergreen broad-leaved and deciduous forests seed rain species composition weather effect.

Small Solutions of Quadratic Equations with Prime Variables in Arithmetic Progressions

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Acta Mathematica Sinica,English Series 2009年第2期25卷 299-320页

作者： Tian ze wang School of Mathematics and Information Sciences He'nan University Kaifeng 475001 P. R. China School of Mathematics and Information Sciences North China University of Water Conservancy and Electric Power Zhengzhou 450011 P. R. China

A necessary and sufficient solvable condition for diagonal quadratic equation with prime variables in arithmetic progressions is given, and the best qualitative bound for small solutions of the equation is obtained,

关键词： quadratic equation prime variable small solution arithmetic progression

A catalyst-free novel synthesis of diethyl carbonate from ethyl carbamate in supercritical ethanol

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Chinese Chemical Letters 2014年第10期25卷 1395-1398页

作者： Li-Cai Zhao Zhi-Qiang Hou Chun-ze Liu yuan-yuan wang Li-Yi Dai Department of Chemistry East China Normal University

Diethyl carbonate has been synthesized via the alcoholysis of ethyl carbamate in supercritical ethanol under catalyst-free *** influences of various parameters such as reaction temperature,reaction time,reaction pressure,ethanol/ethyl molar ratios and reaction loading volume on the yield of DEC were studied *** experimental results indicated that the alcoholysis of ethyl carbamate was greatly improved in supercritical *** optimal reaction conditions were as follows：a reaction temperature of 573 K,a reaction time of 30 min,a reaction pressure of 13.2 MPa,an ethanol/ethyl carbamate molar ratio of 10 and a reactor loading volume of 285 μL *** optimal yield of DEC was 22.9%.

关键词： Supercritical ethanol Diethyl carbonate Ethyl carbamate Alcoholysis

Response of partitioning to cooling rate for different solutes in aluminum alloys

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Journal of Materials Science & Technology 2024年第18期185卷 155-164页

作者： Jiang You Cheng wang Dong Qiu Si-Yu Chen ze-Tian Liu Hui-yuan wang National Key Laboratory of Automotive Chassis Integration and Bionics Jilin UniversityChangchun 130025China Key Laboratory of Automobile Materials of Ministry of Education&School of Materials Science and Engineering Jilin UniversityChangchun 130025China State Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Material Science and EngineeringHebei University of TechnologyTianjin 300130China Center for Additive Manufacturing School of EngineeringRMIT UniversityMelbourneVIC 3001Australia

It is commonly recognized that the cooling rate has a substantial effect on solute partitioning and its resultant microsegregation during *** classical dendrite tip undercooling theory clarifies the mitigation of microsegregation by increasing the cooling ***,most of the studies focused on binary alloys,leaving an open question as to whether the microsegregation of different solutes in a multi-component alloy system exhibits a relieving degree similar to increasing cooling *** a widely used 6022-type Al alloy(Al-0.76Mg-0.93Si-0.2Fe)as a model alloy,the current study reveals that the microsegregation of Mg gets alleviated to the greatest extent,followed by those of Si and Fe when the cooling rate increases from 5 to 128 K/*** phenomenon is attributed to the solute-based difference in response to partitioning to cooling rate(denoted as Rk).We propose a theoretical equation to quantify Rk,and the R_(k)values of solute Mg,Si,and Fe successfully explain the rank of solute partitioning in ***,a broad range of R_(k)values of other commonly used alloying elements in Al alloys were calculated and ranked,delivering a handy tool to predict the microsegregation behavior and sol-ubility of different solute elements upon sub-rapid solidification,which is consistent with experimental *** framework can also be extended to other multi-component alloy systems.

关键词： Solidification Cooling rate Microsegregation Aluminum alloys Solute partitioning

Interplay between creeping fat and gut microbiota: A brand-new perspective on fecal microbiota transplantation in Crohn's disease

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World Journal of Gastroenterology 2025年第2期31卷 138-143页

作者： Ying wang Jie Liu Department of Life Sciences and Medicine South District of Endoscopic CenterThe First Affiliated Hospital of University of Science and Technology of ChinaUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Gastroenterology The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230001Anhui ProvinceChina

Inflammatory bowel disease,particularly Crohn's disease(CD),has been linked to modifications in mesenteric adipose tissue(MAT)and the phenomenon known as"creeping fat"(CrF).The presence of CrF is believed to serve as a predictor for early clinical recurrence following surgical intervention in patients with ***,the incorporation of the mesentery during ileocolic resection for CD has been correlated with a decrease in surgical recurrence,indicating the significant role of MAT in the pathogenesis of *** numerous studies have indicated that dysbiosis of the gut microbiota is a critical factor in the development of CD,the functional implications of translocated microbiota within the MAT of CD patients remain *** manuscript commentary discusses a recent basic research conducted by Wu et *** their study,intestinal bacteria from individuals were transplanted into CD model mice,revealing that fecal microbiota trans-plantation(FMT)from healthy donors alleviated CD symptoms,whereas FMT from CD patients exacerbated these ***,FMT was found to affect intestinal permeability,barrier function,and the levels of proinflammatory factors and ***,these findings suggest that targeting MAT and CrF may hold therapeutic potential for patients with ***,the study did not evaluate the composition of the intestinal microbiota of the donors or the subsequent alterations in the gut ***,the gut microbiota plays a crucial role in the histopathology of CD,and thus,targeting MAT and CrF may represent a promising avenue for treatment in this patient population.

关键词： Crohn's disease Mesenteric adipose tissue Creeping fat Fecal microbiota transplantation Gut microbiota

Artemordins A-S, Cadinane-Type Sesquiterpenoid Dimers from Artemisia ordosica and Their Antihepatoma Activities

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Chinese Journal of Chemistry 2024年第13期42卷 1493-1508页

作者： yuan wang Tian-ze Li Yun-Bao Ma Chang-An Geng Yong-Cui wang Ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Nineteen new cadinane-involving sesquiterpenoid dimers,artemordins A-S(1-—19),together with 13 known SDs(20-32)were isolated from Artemisia *** structures and absolute configurations were established by comprehensive spectral analyses,X-ray single crystal diffraction,theoretical ECD,and NMR ***,artemordins A-F(1—6)were the first examples of two cadinane units constructed by unprecedented C-3−C-15′or C-3−C-13′single bond with an oxido-rearranged 6/5/6/6 fused ring system;artemordins G-K(7-11)were biogenetically connected by[4+2]cycloaddition reaction and artemordins G-J(7-10)possessed a novel 5/6/6/6/6/6/5-heptacyclic fused ring *** L-S(12-19)were formed by esterification,which involved three different types of *** assay suggested that the most active compounds,artemordins B and H(2 and 8),exhibited inhibitory activities on three hepatoma cell lines with IC50 values of 26.9 and 25.1μmol/L(HepG2),29.5 and 18.3μmol/L(Huh7),19.7 and 15.7μmol/L(SK-Hep-1).

关键词： Artemisia ordosica Artemordins A-s Cadinane-type sesquiterpenoid dimers Antihepatoma activities Terpenoids Natural products Cytotoxicity

Austenite Grain Growth in Heat Affected Zone of Zr-Ti Bearing Microalloyed Steel

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Journal of Iron and Steel Research International 2012年第2期19卷 73-78页

作者： ZHENG Lei yuan ze-xi SONG Shen-hua XI Tian-hui wang Qian Department of Materials Science and Engineering Shenzhen Graduate School Harbin Institute of TechnologyShenzhen 518055 Guangdong China School of Materials and Metallurgy Wuhan University of Science andTechnology Wuhan 430081 Hubei China Research and Development Center Wuhan Iron and SteelCorporation Wuhan 430080 Hubei China

Austenite grain sizes in the heat affected zone （HAZ） of a high heat input welded Zr-Ti bearing microal- loyed steel are measured under different welding conditions simulated by a Gleeble-1500 thermal-mechanical simulator. The austenite grain growth is divided into two regimes in terms of temperature. When the temperature is lower than 1 250℃ where the pinning effect of precipitates is strong, the austenite grain size increases slowly with increas- ing peak temperature, but it increases drastically when the temperature is higher than 1 250 ~C where the pinning effect of precipitates is weak. Based on the experimental measurements, an analytical model for predicting the aus- tenite grain size in the heat affected zone is derived. Model predictions indicate that the initial grain size has little effect on the final one, and the grain growth depends mainly on heat input and peak temperature as well as growth activation energy and exponent. With the use of the model, the width of coarse grained heat affected zone （CGHAZ） for a thick plate is predicted.

关键词： welding high heat input microstructure

Radiation dose effects on the morphological development of M_(1) generation pea(Pisum sativum)

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Nuclear Science and Techniques 2021年第11期32卷 63-76页

作者： Da-Peng Xu Hu-yuan Feng Jian-Bin Pan ze-En Yao Jun-Run wang School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Life Sciences Lanzhou UniversityLanzhou 730000China Engineering Research Center for Neutron Application Technology Ministry of EducationLanzhou UniversityLanzhou 730000China

We irradiated pea seeds with neutrons from a ^(252)Cf source and studied the radiation dose effects on various morphological development parameters during the growth of M_(1) generation *** found that in the dose range of 0.51-9.27 Gy,with the increase in neutron-absorbed dose,the morphological development parameters of M_(1) generation peas at the initial seedling stage showed an obvious trend with three *** the development of pea,this trend gradually *** analysis and verification showed that the main trend in the M_(1) generation of pea seeds was an inhibitory effect induced by neutron irradiation and there was a good linear correlation between the inhibitory effect and neutron absorption dose We successfully demonstrated the background removal of mutant plants and defined morphological developmen parameters for peas that match the overall development of *** results will positively impact neutron mutation breeding and automatic agriculture.

关键词： Neutron irradiation Pea(Pisum sativum) ^(252)Cf source Radiation does effects Absorbed dose Morphological development

Direct identification of monolayer rhenium diselenide by an individual diffraction pattern

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Nano Research 2017年第7期10卷 2535-2544页

作者： Zhen Fei Bo wang Ching-Hwa Ho Fang Lin Jun yuan ze Zhang Chuanhong Jin State Key Laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang University Hangzhou 310027 China School of Physical Science and Technology Lanzhou University Lanzhou 730000 China Graduate Institute of Applied Science and Technology Taiwan University of Science and Technology Taipei 106 Taiwan China College of Electronic Engineering South China Agricultural University Guangzhou 510642 China Department of Physics University of York Heslington York YO 10 5DD UK

In the current extensive studies of layered two-dimensional （2D） materials, compared to hexagonal structures such as graphene, hBN, and MoS2, low- symmetry 2D materials have shown great potential for applications in anisotropic devices. Rhenium diselenide （ReSe2） possesses the bulk space group P1 and belongs to the triclinic crystal system with a deformed cadmium-iodide-type structure. Here, we propose an electron diffraction-based method to distinguish the monolayer ReSe2 membrane from multilayer ReSe2 and its two different vertical orientations. Our method is also applicable to other low-symmetry crystal systems, including both triclinic and monoclinic lattices, as long as their third unit-cell basis vectors are not perpendicular to the basal plane. Our experimental results are well explained by kinematical electron diffraction theory and the corresponding simulations. Generalization of our method to other 2D materials, such as ~：raphene, is also discussed.

关键词： rhenium diselenide electron diffraction monolayer reciprocal rel-rod