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Acta Metallurgica Sinica(English Letters) 2001年第5期14卷 341-346页

作者： K.F. Yao, P. Yu, J. Wang, W. fang and M.X. Zheng department of Mechanical Engineering, tsinghua university, beijing 100084, china Dept. of Mech. Eng. Tsinghua Univ. Beijing 100084 China

The influence of high-density pulsing current on the work-hardening behaviour of H0Cr17Ni6Mn3 and 1Cr18Ni9 stainless steels in wire-drawing deformation processes has been studied. It was found that the drawing stress and the work-hardening rate of wires were significantly reduced by applying current pulses in drawing process. The work-hardening behavior of the multi-courses drawing deformation can be well described by Hollomon formula σ=κΕn. With the application of current pulses in drawing deformation, the work-hardening exponents of H0Cr17Ni6Mn3 steel wires and 1Cr18Ni9 stainless steel wires were reduced by 33% and 45%, respectively, and their work-hardening coefficients were reduced by 41% and 47%, respectively. It was also found that the work-hardening coefficient of wires was reduced with the increment of the frequency of current pulses, while the work-hardening exponents of both steels were insensitive to the pulsing frequency.

关键词： Deformation Electric currents Pulsatile flow Strain hardening Wire drawing

RNA Cleavage by N-Phosphoryl Serine in Histidine buffer

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Chinese Chemical Letters 1997年第1期8卷 53-56页

作者： Xiang Hong LI Yuan MA yi CHEN Yu Fen ZHAO(Bio-organic Phosophorus Chemistry Laboratory, department of Chemistry,tsinghua university, beijing, 100084Institute of Chemistry, Chinese Academy sciences, beijing, 100080) TSING HUA UNIV DEPT CHEMBIOORGAN PHOSPHORUS CHEM LABBEIJING 100084PEOPLES R CHINA CHINESE ACAD SCI INST CHEMBEIJING 100080PEOPLES R CHINA

In the presence of histidine, N-(O,O-diisopropyl)phosphoryl serine could catalyze the cleavage of RNA in aqueous solution at neutral pH. The results were detected by sub-marine agarose gel electrophoresis and capillary zone electrophoresis. It was found that at high concentration histidine could cleave the RNA slightly. While the participation of DIPP-Ser could significantly accelerate the cleavage reaction. N-phosphodipeptide---N-(O,O-diisopropyl) Ser-His are proposed to be involved in the mechanism.

关键词： RNA Cleavage by N-Phosphoryl Serine in Histidine buffer Res

Reusable Component Technology in the Development of Agile Supply Chain Management System

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厦门大学学报（自然科学版） 2002年第S1期41卷 264-265页

作者： LAI Guo-ming, CHAI Yue-ting, HE Kang-kang, LIU yi (department of Automation, tsinghua university, beijing 100084, china)

Agile Supply Chain Management (ASCM) is one of the ke y techniques, which support dynamic enterprise alliance and realize agile manufa cturing. but the optimal run of ASCS depends on a good-constructed Agile Supply Chain Management System (ASCMS), so that the materials flow, information flow a nd funding flow in the supply chain are used with high efficiency. The requireme nts of ASCMS are constantly changeable, which requires that ASCMS has dynamical reuse, integration and open interface. Reusable components theory is one of the most important directions of software engineering. It’s a feasible approach to solve software crisis and to increase software productivity and quality. ASCMS d eveloped with reusable components can easily be re-constructed, and has good op en interfaces. It will also sharply shorten the development life circle of syste m, and avoid unnecessary errors that result from the process of re-developing t hose components. In order to develop ASCMS based on reusable components quickly, the first thing we need to do is to construct the framework for ASCMS called system architecture . The framework referred in this context is not only a reference system of ASCMS , but also the operation system (including run-time library and communication p rotocols), which the ASCMS determined. So we can abstract logic units of the sys tem (they are the logic base of the ASCMS components), and the relationships amo ng them. And the operation system and communication protocols provide these comp onents with a running platform. Of course, the most important thing is to constr uct an abundant components depository. Components in the depository should h ave some properties such as: (1) Components should be built upon a specific oper ation system (e.g., windows) and standard communication protocols (e.g., IIOP in CORBA’s specification); (2)Self-containment, that shows it’s unnecessary to include other components when some component is reused since that component cont ains

关键词： supply chain ASCMS reusable component CORBA

Recovery of functions via their irregular sampling values

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Chinese Science bulletin 1998年第4期43卷 268-271页

作者： fang Gensun department of Mathematics, beijing Normal university, beijing 100875, china department of Mathematics Lkijing Normal University Beijing China

It is proved that if a function can be completely reconstructed by tempered splines which satisfy the real Kiesz basis condition as the degree of spline goes to infinity, then the function is band limited.

关键词： band limited function cardinal splines irregular sampling.

Differentiation Effect of Pentacoordinate Phosphorus on Carbohydrate Reaction

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Chinese Chemical Letters 1999年第5期10卷 387-388页

作者： Yong JU yi CHEN Yu Fen ZHAO (Bioorganic Phosphorus Chemistry Laboratory. department of Chemistry.tsinghua university. beijing 100084) Tsing Hua Univ Dept Chem Bioorgan Phosphorus Chem Lab Beijing 100084 Peoples R China

The reaction between D-glucose, D-ribose and 2, 2,2-trimethoxy-4, 5-diphenyl-2, 2-dihydro-1, 3, 2-dioxaphospholene were investigates by P-31 NMR and FAB-MS. The results showed that there were a lot of differences in the reactions via pentacoordinate phosphorus compound, and it should give it significant clue to the metabolism of carbohydrate phosphate in nature.

关键词： carbohydrate pentacoordinate oxyphosphorane biomimic mechanism

Studies on Human Immunoglobulin G from GBS Patient (Ⅲ)-The Determination of Molecular Weight of Human Immunoglobulin G by Capillary SDS Gel Electrophoresis

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Chinese Chemical Letters 1999年第1期10卷 55-58页

作者： Qin Hua RU yi Ming WANG Guo An LUO(department of Chemistry. School of Life Science and Engineering,tsinghua university. beijing, 100084) department of Chemistry Sch. of Life Science and Engineering Tsinghua University Beijing 100084 China

Guillain-Barre syndrome (GBS) is considered to be an autoimmune disorder of peripheralnervous system. In this paper. capillary SDS gel electrophoresis was performed on neutral coatedfused-silica capillary to determine... 详细信息

关键词： Immunoglobulin G Guillain-Barre syndrome Capillary SDS gel electrophoresis Molecular weight of protein

Fault Detection of Networked Control Systems with Uncertain Time-Varying Delay and Quantization Error

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Journal of Shanghai Jiaotong university(Science) 2011年第5期16卷 513-518页

作者：李斌万一鸣叶昊 department of Automation Tsinghua University

Problems related to fault detection of networked control systems (NCSs) with both uncertain time-varying delay and quantization error are studied in this paper. A novel model with the form of polytopic uncertainty is given to represent the influences of both the time-varying delay and the quantization error, and then the reference model based method is used to design the residual generator that is robust to both unknown network-induced delay and unknown inputs. A numerical example is also given to illustrate the merits of the presented method. The proposed method can be regarded as an extension of the authors' former work, which can only deal with time-varying delay.

关键词： fault detection networked control systems (NCSs) delay quantization error polytopic uncertainty

More than just aligning the teeth:Clear aligners with multifunctional prowess

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Nano Research 2024年第8期17卷 7665-7674页

作者： Yang Chen Lei-Ming Cao Nian-Nian Zhong Zi-Zhan Li Lin-Lin bu fang-yi Huo Hong He State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool and Hospital of StomatologyWuhan UniversityWuhan 430079China department of Oral and Maxillofacial-Head Neck Oncology School and Hospital of StomatologyWuhan UniversityWuhan 430079China department of Zhuankou Clinical Branches School and Hospital of StomatologyWuhan UniversityWuhan 430000China department of Orthodontics School and Hospital of StomatologyWuhan UniversityWuhan 430079China

With the increasing demand for beauty and health,clear aligners(CAs)have been widely applied among patients with ***,patients treated with CAs also face some potential complications,such as demineralization,dental caries,and periodontal *** addition,some patients have additional needs to improve their quality of life,such as bleaching *** order to prevent or solve these problems,the modification of CAs is a promising method because their extensive long-term contact with tooth surfaces makes them ideal devices for implementing adjuvant medical *** this review,we discuss various advanced CAs with medical functions based on the clinical needs of *** far as we know,the additional functions of CAs mainly include antibacterial,remineralization,whitening,and accelerating tooth *** functions are achieved by two major pathways,the combination of CAs with drugs/biomaterials and increasing the capacity or affinity of *** addition,we discuss the current limitations of in vitro experiments which are designed to explore the effectiveness and properties of novel CAs,and the challenges of bringing a multifunctional appliance from proposal to clinical *** the end of this review,we provide insights into the broader prospects for the improvement of CAs.

关键词： advanced clear aligners medical device modification drug delivery system personalized medicine

Effects of chebulinic acid on differentiation of human leukemia K562 cells

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Acta Pharmacologica Sinica 2004年第2期 105-112页

作者： Zong-chun yi, Zhao WANG2, Hai-xia LI, Ming-jie LIU, Rong-cong WU, Xiao-hui WANG department of Biological sciences and Biotechnology, tsinghua university, beijing 100084, china

AIM: To study effects of chebulinic acid on erythroid and megakaryocytic differentiation in K562 cells. METHODS: The benzidine staining method was used to evaluate hemoglobin synthesis; the expression of erythroid specific glycophorin A (GPA) protein and megakaryocytic surface marker CD61 was determined by flow cytometry using fluorescence labeled antibodies; erythroid and megakaryocytic mRNA expression was analyzed by RT-PCR. RESULTS: During erythroid differentiation induced by butyric acid (BA) or hemin, chebulinic acid not only inhib- ited the hemoglobin synthesis of BA- and hemin-treated K562 cells in concentration-dependant manner with IC50 of 4 μmol/L and 40 μmol/L respectively, but also inhibited another erythroid differentiation marker acetylcholinesterase at the concentration of 50 μmol/L in the cells either treated or untreated with each erythroid differentiation inducers, whereas chebulinic acid 50 μmol/L did not change GPA protein expression in these cells significantly. When K562 cells were treated with TPA 50 μg/L for 72 h to induce megakaryocytic differentiation, the presence of chebulinic acid 50 μmol/L slightly provoked the decrease of GPA protein expression induced by TPA. Chebulinic acid did not change the TPA-induced CD61 expression at the same concentration. Chebulinic acid also reduced the mRNA levels of erythroid relative genes including γ-globin, PBGD, NF-E2, and GATA-1 genes in K562 cells either treated or untreated with BA, whereas chebulinic acid upregulated the mRNA levels of GATA-2 transcription factor in these cells. CONCLUSION: Chebulinic acid had inhibitory effect on erythroid differentiation likely through changing transcriptional activation of differentiation relative genes, which suggests that chebulinic acid or other tannins might influence the efficiency of some anti-tumor drugs-induced differentiation or the hematopoiesis processes.

关键词： K562cells chebulinic acid butyrates hemin glycophorin CD61 antigen gene expression regulation celldifferentiation

Studies on repairing of hemisected thoracic spinal cord of adult rats by using a chitosan tube filled with alginate fibers

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Progress in Natural Science:Materials International 2006年第10期16卷 1051-1055页

作者： LI Xiaoguang, YANG Zhaoyang and YANG yi ( beijing Center for Neural Regeneration and Repairing, Capital university of Medical sciences, beijing 100054, china.department of Bioengineering, beijing university of Aeronautics and Astronautics, beijing 100083, china National Center of Biomedical Analysis, beijing 100850, china) [a]beijing Center for Neural Regeneration and Repairing Capital University of Medical Sciences Beijing China [b]department of Bioengineering Beijing University of Aeronautics and Astronautics Beijing China [c]National Center of Biomedical Analysis Beijing China

A chitosan tube filled with alginate fibers was implanted into the injured spinal cord of a rat for repairing the damaged tissue. Twelve months after the operation, the morphological observation demonstrated that this chitosan tube could induce regeneration of myelinated and non-myelinated axons and blood vessels. The Basso-Beattie-Bresnahan (BBB) behavioral evaluation confirmed that the implants played a key role in the long-term restoration of rats motor functions. It is a promising start in the treatment of the patients with the injury of the spinal cord.

关键词： spinal cord injury regeneration function recovery chitosan alginate behavioral evaluation.