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Study on the two and three-parameter working stability regions of 3.-TZP suspension

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Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2, ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. Department of chemistry, Qingdao university, Qingdao 266071, china 2. Department of chemistry, tsinghua university, beijing 100084, china 3. Department of Physics, Qingdao university, Qingdao 266071, china 1. Department of chemistry Qingdao University Qingdao 266071 China 2. Department of chemistry Tsinghua University Beijing 100084 China 3. Department of Physics Qingdao University Qingdao 266071 China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.

Reconstruct recent multi-population migration history by using identical-by-descent sharing

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Journal of Genetics and Genomics 2024年第6期51卷 642-651页

作者： Wenxiao Zhang Kai Yuan ru Wen Haifang li Xumin Ni School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044China The Stanley Center for Psychiatric Research Broad Institute of MIT and HarvardCambridgeMA 02142USA Baidu Incorporated Beijing 100085China

Identical-by-descent(IBD)is a fundamental genomic characteristic in population genetics and has been widely used for population history ***,limited by the nature of IBD,which could only capture the relationship between two individuals/haplotypes,existing IBD-based history inference is constrained to two *** this study,we propose a framework by leveraging IBD sharing in multipopulation and develop a method,MatrixiBD,to reconstruct recent multi-population migration ***,we employ the structured coalescent theory to precisely model the genealogical process and then estimate the IBD sharing across multiple *** our model,we establish a theoretical connection between migration history and IBD *** method is rigorously evaluated through simulations,revealing its remarkable accuracy and ***,we apply MatrixiBD to Central and South Asia in the Human Genome Diversity Project and successfully reconstruct the recent migration history of three closely related populations in South *** taking into account the IBD sharing across multiple populations simultaneously,MatrixlBD enables us to attain clearer and more comprehensive insights into the history of regions characterized by complex migration dynamics,providing a holistic perspective on intricate patterns embedded within the recent population migration history.

关键词： Population genetics IBD sharing Migration history Structured coalescent theory Gene flow

The effects of various factors on spontaneous imbibition in tight oil reservoirs

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Petroleum Science 2024年第1期21卷 315-326页

作者： Cheng liu Tian-ru Wang Qing You Yue-Chun Du Guang Zhao Cai-li Dai School of Energy Resources China University of GeosciencesBeijing100083PR China School of Petroleum Engineering China University of PetroleumQingdao266580ShandongPR China

Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imbibition within the reservoir. Several variables influence the eventual recovery rate within this procedure, including slickwater composition, formation temperature, degree of reservoir fracture development, and the reservoir characteristics. Nonetheless, the underlying mechanisms governing these influences remain relatively understudied. In this investigation, using the Chang-7 block of the Changqing Oilfield as the study site, we employ EM-3. slickwater fracturing fluid to explore the effects of the drag-reducing agent concentration, imbibition temperature, core permeability, and core fracture development on spontaneous imbibition. An elevated drag-reducing agent concentration is observed to diminish the degree of medium and small pore utilization. Furthermore, higher temperatures and an augmented permeability enhance the fluid flow properties, thereby contributing to an increased utilization rate across all pore sizes. Reduced fracture development results in a lower fluid utilization across diverse pore types. This study deepens our understanding of the pivotal factors affecting spontaneous imbibition in tight reservoirs following fracturing. The findings act as theoretical, technical, and scientific foundations for optimizing fracturing strategies in tight oil reservoir transformations.

关键词： Tight oil reservoir Spontaneous imbibition Nuclear magnetic resonance Slickwater fracturing fluid Fluid utilization degree

Plant-based dietary patterns and risk of esophageal cancer:A prospective cohort study spanning 17 years

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Chinese Journal of Cancer Research 2024年第1期36卷 36-45页

作者： Xiaorui Zhang Feifan He Jiayue li ru Chen Xinqing li li li Fen liu Shaoming Wang Wenqiang Wei Department of Epidemiology and Health Statistics School of Public HealthBeijing Municipal Key Laboratory of Clinical EpidemiologyCapital Medical UniversityBeijing 100069China National Central Cancer Registry office National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Cancer Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Objective: Plant-based diets have multiple health benefits for cancers;however, little is known about the association between plant-based dietary patterns and esophageal cancer(EC).This study presents an investigation of the prospective associations among three predefined indices of plant-based dietary patterns and the risk of ***: We performed endoscopic screening for 15,709 participants aged 40-69 years from two high-risk areas of china from January 2005 to December 2009 and followed the cohort until December 3., 2022. The overall plant-based diet index(PDI), healthful plant-based diet index(h PDI), and unhealthful plant-based diet index(u PDI), were calculated using survey responses to assess dietary patterns. We applied Cox proportional hazard regression to estimate the multivariable hazard ratios(HRs) and 95% confidence intervals(95% CIs) of EC across 3.lant-based diet indices and further stratified the analysis by ***: The final study sample included 15,184 participants in the cohort. During a follow-up of 219,3.5person-years, 176 patients with EC were identified. When the highest quartile was compared with the lowest quartile, the pooled multivariable-adjusted HR of EC was 0.50(95% CI, 0.3.-0.77) for h PDI. In addition, the HR per 10-point increase in the h PDI score was 0.42(95% CI, 0.27-0.66) for ECs. Conversely, u PDI was positively associated with the risk of EC, and the HR was 1.80(95% CI, 1.16-2.82). The HR per 10-point increase in the u PDI score was 1.90(95% CI, 1.26-2.88) for ECs. The associations between these scores and the risk of EC were consistent in most subgroups. These results remained robust in sensitivity ***: A healthy plant-based dietary pattern was associated with a reduced risk of EC. Emphasizing the healthiness and quality of plant-based diets may be important for preventing the development of EC.

关键词： Esophageal cancer diet dietary pattern epidemiology nutrition prospective cohort study

Cretaceous crown male ant reveals the rise of modern lineages

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Zoological Research 2024年第5期45卷 983-989页

作者： Qiong Wu Alexander G.Radchenko Michael S.Engel Xiao-Qin li Hong-ru Yang Xing-ru li Chung-Kun Shih Dong Ren Tai-Ping Gao College of life Sciences Capital Normal UniversityBeijing 100048China I.I.Schmalhausen Institute of Zoology NAS of UkraineKiev 01054Ukraine Division of Invertebrate Zoology American Museum of Natural HistoryNew York 10024-5192USA Facultad de Ciencias Biológicas Universidad Nacional Mayor de San MarcosLima 11-0058Perú Departamento de Entomología Museo de Historia NaturalUniversidad Nacional Mayor de San MarcosLima 15072Perú Department of chemistry Analytical and Testing CenterCapital Normal UniversityBeijing 100048China Department of Paleobiology National Museum of Natural HistorySmithsonian InstitutionWashington DC 20013-7012USA

Most described Mesozoic ants belong to stem groups that existed only during the Cretaceous ***,the earliest known crown ants were dated to the Turonian(Late Cretaceous,ca.94-90 million years ago(Ma))deposits found in the USA,Kazakhstan,and ***,the recent discovery of an alate male ant in Kachin amber from the earliest Cenomanian(ca.99 Ma),representing a new genus and species,Antiquiformica alata,revises the narrative on ant *** can be distinctly differentiated from all known male stem ants by its geniculate antennae with elongated scape,extending far beyond the occipital margin of the head and half the length of the funiculus,as well as its partly reduced forewing ***,the combination of a one-segmented waist with a well-developed node,elongated scape extending beyond the occipital margin,and reduced forewing venation,particularly the completely reduced m-cu and rs-m crossveins and absence of rm and mcu closed cells,firmly places the fossil within the extant subfamily *** transform infrared spectroscopy(FTIR)confirmed that the amber containing Antiquiformica alata originated from the Kachin mines in *** discovery significantly revises our understanding of the early evolution of *** presence of Antiquiformica in Cenomanian amber indicates that the subfamily Formicinae emerged at least by the start of the Late Cretaceous,with crown ants likely originating earlier during the earliest Cretaceous or possibly the Late Jurassic,although paleontological evidence is lacking to support the latter hypothesis.

关键词： Formicidae Formicinae Morphology Taxonomy Antiquiformica alata Paleontology Kachin amber

Coacervate Structures of CdI_2 Thin Film Grown during Phase Transformation

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Journal of Materials Science & Technology 1997年第4期13卷 296-298页

作者： Xiaoyan YE and lili CAO(Dept. of chemistry,{3., beijing 100084, china)Jizhong ZHANG and Hengde li(Dept. of Materials Scieuce & Engineering,{3., beijing 100084, china) Dept. of chemistry Tsinghua University Beijing 100084 China Dept. of Materials Science and Engineering Tsinghua University Beijing 100084 China

The microstructure of CdI2 thin film grown during vapor-phase deposition was investigated by scanning electron microscopy (SEM). The thin film deposited on Si crystal consists of numerous sunflower-like aggregates. These aggregates display well self-assembly characteristics. The size of Sunflower-like aggregates is between 12 and 44 μm. Each sunflower-like aggregate is surrounded with many adjacent wings-'petals'. The structure of central region of the 'sunflower' is obviously difFerent from that of the 'petal'. Electron spectroscopy for chemical analysis (ESCA) was employed in determining the chemical valence of the thin film. Self-organization efFect is used to explain the coring growth process of CdI2 thin film

关键词： Thin Coacervate Structures of CdI2 Thin Film Grown during Phase Transformation

Surface effects of monolayer-protected gold nanoparticles on the redox reactions between ferricyanide and thiosulfate

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Science china chemistry 2005年第5期48卷 424-430页

作者： li Di1, SUN Chunyan1, HUANG Yunjie1, li Jinghong1,2 & CHEN Shaowei3.1. State Key Laboratory of Electroanalytical chemistry, Changchun Institute of Applied chemistry, Chinese Academy of Sciences, Changchun 13.022, china 2. Department of chemistry, tsinghua university, beijing 100084, china 3. Department of chemistry, university of California, Santa C{13.z, Santa C{13.z, CA 95064, USA 1. State Key Laboratory of Electroanalytical chemistry Changchun Institute of Applied chemistry Chinese Academy of Sciences 130022 Changchun China 2. Department of chemistry Tsinghua University 100084 Beijing China 3. Department of chemistry University of California 95064 Santa Cruz Santa Cruz CA USA

Electron transfer through the self-assembled monolayers (SAMs) on gold nanopar-ticles is investigated by using the monolayer protected gold nanoclusters (MPCs) as elec-tron-transfer mediators. 3.Mercaptopropionic acid (MPA) and 11-meraptoundecanoic acid (MUA) MPCs were employed to catalyze the redox reaction between potassium ferricyanide and sodium thiosulfate. The catalytic mechanism was proposed that the MPCs act as diffusing elec-tron-mediators and electron transfers to and from the MPCs surface. Therefore the electron transfer rate through the capping layers would be proportional to the MPCs catalyzed reaction rate, which was monitored by the UV absorbance of ferricyanide. The calculated apparent rate constant was orders of magnitude smaller than that of the maximum of tunneling current, which was attributed to the splited energy level of the nanoscale particles.

关键词： electron transfer, three-dimensional self-assembled monolayers, redox reaction, electron transfer mediator, surface effect.

Progress on immuno-microenvironment and immune-related therapies in patients with pseudomyxoma peritonei

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Cancer Biology & Medicine 2024年第7期21卷 586-605页

作者： Qidi Zhao Tian Wei ru Ma Yubin Fu rui Yang Yandong Su Yang Yu Bing li Yan li School of Clinical Medicine Tsinghua UniversityBeijing 100084China Department of Surgical Oncology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China Department of Peritoneal Cancer Surgery Bejing Shijitan HospitalCapital Medical UniversityBejing 100038China

Pseudomyxoma peritonei(PMP) is an indolent malignant syndrome. The standard treatment for PMP is cytoreductive surgery combined with intraperitoneal hyperthermic chemotherapy(CRS + HIPEC). However, the high recurrence rate and latent clinical symptoms and signs are major obstacles to further improving clinical outcomes. Moreover, patients in advanced stages receive little benefit from CRS + HIPEC due to widespread intraperitoneal metastases. Another challenge in PMP treatment involves the progressive sclerosis of PMP cell-secreted mucus, which is often increased due to activating mutations in the gene coding for guanine nucleotide-binding protein alpha subunit(GNAS). Consequently, the development of other PMP therapies is urgently needed. Several immune-related therapies have shown promise, including the use of bacterium-derived non-specific immunogenic agents, radioimmunotherapeutic agents, and tumor cell-derived neoantigens, but a well-recognized immunotherapy has not been established. In this review the roles of GNAS mutations in the promotion of mucin secretion and disease development are discussed. In addition, the immunologic features of the PMP microenvironment and immune-associated treatments are discussed to summarize the current understanding of key features of the disease and to facilitate the development of immunotherapies.

关键词： Pseudomyxoma peritonei tumor immuno-microenvironment immune-related therapy mucin 2 GNAS mutation

A MESSAGE-DRIVING FORMAliSM FOR MODEliNG AND SIMULATION OF MULTI-AGENT SUPPLY CHAIN SYSTEMS

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Journal of Systems Science and Systems Engineering 2011年第4期20卷 385-399页

作者： Wenzhe TAN1 Yueting CHAI2 Yi liU3.1Department of Automation, tsinghua university, beijing, 100084,{3. 2Department of Automation, tsinghua university, beijing, 100084,{3. 3.epartment of Automation, tsinghua university, beijing, 100084,{3. Department of Automation Tsinghua University Beijing China

To acquire a competitive advantage in the expanding market, manufacturing enterprises should be able to manage their supply chains as effectively as possible. It is now becoming popular to model supply chains as multi-agent systems and use discrete event simulation to learn more about their behaviors or investigate the implications of alternative configurations. In order to enhance the computational efficiency and keep the simulation credibility, this paper proposes a message-driving formalism for the simulation of multi-agent supply chain systems. Through the message-driving formalism, the problem of shared variables is addressed and the parallel operation of agents is implemented. Simulation experiments with a prototype implementation show that the message-driving formalism is able to provide credible results in significantly less simulation time.

关键词： Supply chain multi-agent system modeling and simulation parallel discrete event simulation message-driving formalism