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A new method for the synthesis of molybdovanadophosphoric heteropoly acids and their catalytic activities

ZHANG Fumin, GUO Maiping, GE Hanqing, WANG Jun

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 296-299 doi: 10.1007/s11705-007-0054-0

摘要： An environmentally benign method for the synthesis of heteropoly acids HPMoVO·HO (PMoV, = 1−3) was developed by the reaction of an aqueous slurry which contained stoichiometric amounts of MoO, VO and HPO. Characterization of the as-synthesized catalysts with inductively coupled plasma (ICP) elemental analysis, thermogravimetry (TG), X-ray diffraction (XRD) and infrared (IR) spectroscopy indicated that V ions substituted for Mo ions in Keggin-type phosphomolybdic acid. The as-synthesized samples were found to be an efficient catalyst for the hydroxylation of benzene which was carried out in a mixed solvent of acetonitrile and acetic acid with aqueous hydrogen peroxide as oxidant. PMoV exhibi ted the highest benzene conversion of 34.5% with phenol selectivity of 100%.

关键词： conversion     heteropoly     Characterization     efficient catalyst     Keggin-type phosphomolybdic    

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Design and analysis of the gripper mechanism based on generalized parallel mechanisms with configurable moving platform

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 765-781 doi: 10.1007/s11465-021-0655-1

摘要： Generalized parallel mechanisms with a configurable moving platform have become popular in the research field of parallel mechanism. This type of gripper mechanism can be applied to grasp large or heavy objects in different environments that are dangerous and complex for humans. This study proposes a family of novel (5 + 1) degrees of freedom (three translations and two rotations plus an additional grasping motion) gripper mechanisms based on the generalized parallel mechanisms with a configurable moving platform. First, the configurable moving platform, which is a closed loop, is designed for grasping manipulation. The hybrid topological arrangement is determined to improve the stiffness of the manipulator and realize high load-to-weight ratios. A sufficient rule based on Lie group theory is proposed to synthesize the mechanism. The hybrid limb structure is also enumerated. A family of novel gripper mechanisms can be assembled through the hybrid limbs by satisfying the rule. Two examples of the gripper mechanisms with and without parallelogram pairs are shown in this study. A kinematic analysis of the example mechanism is presented. The workspace shows that the mechanism possesses high rotational capability. In addition, a stiffness analysis is performed.

关键词： generalized parallel mechanism     configurable moving platform     gripper mechanism     type synthesis     kinematic analysis    

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单自由度平面闭链机构构型方法的研究

张美麟,张晔,杨治义

《中国工程科学》 2002年 第4卷 第6期   页码 5-8

摘要：

提出了一种关于自由度平面闭链机构的构型方法，即“平面图形构造方法”。利用这种方法进行机构结构综合的主要过程是：先根据机械功能确定运动链的组成成分；再按这些成分构造平面图；最后在平面图上进行机构的构型和变异，并将其中结构最优者转换为机构简图。

关键词： 机构     运动链     平面图    

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New practice in semaglutide on type-2 diabetes and obesity: clinical evidence and expectation

《医学前沿（英文）》 2022年 第16卷 第1期   页码 17-24 doi: 10.1007/s11684-021-0873-2

摘要： Obesity is an important risk factor of type 2 diabetes (T2D), which has become an important factor threatening human health. However, no perfect drug choice for obesity exists. Semaglutide is a kind of human glucagon-like peptide-1 (GLP-1) analog that promotes insulin secretion while inhibiting glucagon secretion through a glucose concentration-dependent mechanism. GLP-1 can also delay stomach emptying and suppress appetite to help lose weight. This review summarizes clinical evidence of the semaglutide effect on T2D and obesity and establishes expectations on future clinical trials for obesity treatment.

关键词： semaglutide     type 2 diabetes     obesity    

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Personalized medicine of type 2 diabetes

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《医学前沿（英文）》 2013年 第7卷 第1期   页码 1-3 doi: 10.1007/s11684-013-0241-y

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Immunological and virological characteristics of human immunodeficiency virus type 1 superinfection:

null

《医学前沿（英文）》 2017年 第11卷 第4期   页码 480-489 doi: 10.1007/s11684-017-0594-8

摘要：

Superinfection is frequently detected among individuals infected by human immunodeficiency virus type I (HIV-1). Superinfection occurs at similar frequencies at acute and chronic infection stages but less frequently than primary infection. This observation indicates that the immune responses elicited by natural HIV-1 infection may play a role in curb of superinfection; however, these responses are not sufficiently strong to completely prevent superinfection. Thus, a successful HIV-1 vaccine likely needs to induce more potent and broader immune responses than those elicited by primary infection. On the other hand, potent and broad neutralization responses are more often detected after superinfection than during monoinfection. This suggests that broadly neutralizing antibodies are more likely induced by sequential immunization of multiple different immunogens than with only one form of envelope glycoprotein immunogens. Understanding why the protection from superinfection by immunity induced by primary infection is insufficient and if superinfection can lead to cross-reactive immune responses will be highly informative for HIV-1 vaccine design.

关键词： human immunodeficiency virus type I     superinfection     incidence     immune response    

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Automated synthesis of steady-state continuous processes using reinforcement learning

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 288-302 doi: 10.1007/s11705-021-2055-9

摘要： Automated flowsheet synthesis is an important field in computer-aided process engineering. The present work demonstrates how reinforcement learning can be used for automated flowsheet synthesis without any heuristics or prior knowledge of conceptual design. The environment consists of a steady-state flowsheet simulator that contains all physical knowledge. An agent is trained to take discrete actions and sequentially build up flowsheets that solve a given process problem. A novel method named SynGameZero is developed to ensure good exploration schemes in the complex problem. Therein, flowsheet synthesis is modelled as a game of two competing players. The agent plays this game against itself during training and consists of an artificial neural network and a tree search for forward planning. The method is applied successfully to a reaction-distillation process in a quaternary system.

关键词： automated process synthesis     flowsheet synthesis     artificial intelligence     machine learning     reinforcement learning    

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Metabolomics in human type 2 diabetes research

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《医学前沿（英文）》 2013年 第7卷 第1期   页码 4-13 doi: 10.1007/s11684-013-0248-4

摘要：

The high prevalence of diabetes and diabetic complications has caused a huge burden on the modern society. Although scientific advances have led to effective strategies for preventing and treating diabetes over the past several decades, little progress has been made toward curing the disease or even getting it under control, from a public health and overall societal standpoint. There is still a lack of reliable biomarkers indicative of metabolic alterations associated with diabetes and different drug responses, highlighting the need for the development of early diagnostic and prognostic markers for diabetes and diabetic complications. The emergence of metabolomics has allowed researchers to systemically measure the small molecule metabolites, which are sensitive to the changes of both environmental and genetic factors and therefore, could be regarded as the link between genotypes and phenotypes. During the last decade, the progression made in metabolomics has provided insightful information on disease development and disease onset prediction. Recent studies using metabolomics approach coupled with statistical tools to predict incident diabetes revealed a number of metabolites that are significantly altered, including branched-chain and aromatic amino acids, such as isoleucine, leucine, valine, tyrosine and phenylalanine, as diagnostic or highly-significant predictors of future diabetes. This review summarizes the current findings of metabolomic studies in human investigations with the most common form of diabetes, type 2 diabetes.

关键词： metabolomics     type 2 diabetes     metabolic pathway     mass spectrometry     nuclear magnetic resonance (NMR)    

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Correction to: Effect of wood dust type on mechanical properties, wear behavior, biodegradability, and

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 1071-1071 doi: 10.1007/s11709-021-0736-6

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The mechanisms linking adiposopathy to type 2 diabetes

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《医学前沿（英文）》 2013年 第7卷 第4期   页码 433-444 doi: 10.1007/s11684-013-0288-9

摘要：

Obesity is defined as excessive accumulation of body fat in proportion to body size. When obesity occurs, the functions of adipose tissue may be deregulated, which is termed as adiposopathy. Adiposopathy is an independent risk factor for many diseases, including diabetes and cardiovascular diseases. In overweight or obese subjects with adiposopathy, hyperlipidemia exerts lipotoxicity in pancreatic islet and liver and induces pancreatic β cell dysfunction and liver insulin resistance, which are the decisive factors causing type 2 diabetes. Moreover, adipokines have been shown to play important roles in the regulation of glucose homeostasis. When adiposopathy occurs, abnormal changes in the serum adipokine profile correlate with the development and progression of pancreatic β cell dysfunction and insulin resistance in peripheral tissue. The current paper briefly discusses the latest findings regarding the effects of adiposopathy-related lipotoxicity and cytokine toxicity on the development of type 2 diabetes.

关键词： obesity     adiposopathy     lipotoxicity     adipokines     diabetes    

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Mechanical performance analysis and stiffness test of a new type of suspension bridge

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1160-1180 doi: 10.1007/s11709-021-0760-6

摘要： A new type of suspension bridge is proposed based on the gravity stiffness principle. Compared with a conventional suspension bridge, the proposed bridge adds rigid webs and cross braces. The rigid webs connect the main cable and main girder to form a truss that can improve the bending stiffness of the bridge. The cross braces connect the main cables to form a closed space truss structure that can improve the torsional stiffness of the bridge. The rigid webs and cross braces are installed after the construction of a conventional suspension bridge is completed to resist different loads with different structural forms. A new type of railway suspension bridge with a span of 340 m and a highway suspension bridge with a span of 1020 m were designed and analysed using the finite element method. The stress, deflection of the girders, unbalanced forces of the main towers, and natural frequencies were compared with those of conventional suspension bridges. A stiffness test was carried out on the new type of suspension bridge with a small span, and the results were compared with those for a conventional bridge. The results showed that the new suspension bridge had a better performance than the conventional suspension bridge.

关键词： new type of suspension bridge     stiffness test     mechanical performance     railway bridge     space truss    

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Targeted therapy of desmoid-type fibromatosis: mechanism, current situation, and future prospects

Zhen Wang, Jianhui Wu, Xiuyun Tian, Chunyi Hao

《医学前沿（英文）》 2019年 第13卷 第4期   页码 427-437 doi: 10.1007/s11684-018-0672-6

摘要： Desmoid-type fibromatosis (DF) is a rare monoclonal fibroblastic proliferation that is characterized by locally infiltrative but rarely metastatic lesions. Tyrosine kinase and γ-secretase inhibitors are primarily used in the targeted therapy of DF. The use of these drugs, however, is mainly based on the recommendations of retrospective studies with small sample sizes. Previous studies that focused on the mechanism, efficacy, and safety of targeted therapy for DF were reviewed to provide references for clinical applications and research. The efficacy and safety of targeted therapy were compared with those of other systemic therapy options. Targeted therapy does not provide considerable advantages in efficacy and safety over other medical treatments and is usually applied after the failure of antihormonal therapies, nonsteroidal anti-inflammatory drugs, and chemotherapy. Further studies are required to explore the mechanism, indications, and appropriate drug dosage of the targeted therapy of DF.

关键词： targeted therapy     desmoid-type fibromatosis     tyrosine kinase inhibitor     γ-secretase inhibitor    

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Development of an axial-type fan with an optimization method

Chong-hyun CHO, Soo-yong CHO, Chaesil KIM,

《能源前沿（英文）》 2009年 第3卷 第4期   页码 414-422 doi: 10.1007/s11708-009-0038-5

摘要： An axial-type fan that operates at a relative total pressure of 671Pa and a static pressure of 560Pa with a flowrate of 416.6m/min is developed using an optimization technique based on the gradient method. Prior to the optimization of the fan blade, a three-dimensional axial-type fan blade is designed based on the free-vortex method along the radial direction. Twelve design variables are applied to the optimization of the rotor blade, and one design variable is selected for optimizing a stator which is located behind the rotor to support a fan-driving motor. The total and static pressure are applied to the restriction condition with the operating flowrate on the design point, and the efficiency is chosen as the response variable to be maximized. Through these procedures, an initial axial-fan blade designed by the free vortex method is modified to increase the efficiency with a satisfactory operating condition. The optimized fan is tested and compared with the performance obtained with the same class fan to figure out the optimization effect. The test results show that the optimized fan not only satisfies the restriction conditions but also operates at the same efficiency even though the tip clearance of the optimized fan is greater than 30%. The experimental and numerical tests show that this optimization method can improve the efficiency and operating pressures on axial-type fans.

关键词： axial-type fan     gradient method     free-vortex method     design variable     total pressure     static pressure     operating flowrate    

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Low-temperature CO oxidation over Au-doped 13X-type zeolite catalysts: preparation and catalytic activity

Qing YE, Donghui LI, Jun ZHAO, Jiansheng ZHAO, Tianfang KANG, Shuiyuan CHENG

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 497-504 doi: 10.1007/s11783-011-0256-z

摘要： Au-supported 13X-type zeolite (Au/13X) was synthesized using a common deposition–precipitation (DP) method with a solution of sodium carbonate as a precipitate agent. Further testing was conducted to test for catalytic oxidation of CO. A study was conducted on the effects of different preparation conditions (i.e., chloroauric acid concentration, solution temperature, pH of solution, and calcinations temperature) on Au/13X for CO oxidation. In respect to the catalytic activity, the relationship between different the preparation conditions and gold particles in 13X zeolite was analyzed using X-ray diffraction, TEM and XPS. The activity of Au/13X catalysts in CO oxidation was dependent on the chloroauric acid concentration. From XRD results, a higher chloroauric acid concentration induced larger gold nanoparticles, which resulted in lower catalytic activity. Results revealed that higher temperatures induced higher Au loading, homogeneous deposit, and smaller gold clusters on the support of 13X, resulting in higher CO activity. Furthermore, a pH of 5 or 6 generated greater amounts of Au loading and smaller Au particles on 13X than at a pH of 8 or 9. This may be a result of an effective exchange between and Au(OH) Cl on specific surface sites of zeolite under the pH’s 5 and 6. The sample calcined at 300°C showed the highest activity, which may be due to the sample’s calcined at 200°C inability to decompose completely to metallic gold while the sample calcined at 400°C had larger particles of gold deposited on the support. It can be concluded from this study that Au/13X prepared from a gold solution with an initial chloroauric acid solution concentration of 1.5 × 10 mol·L gold solution pH of 6, solution temperature of around 90°C, and a calcination temperature of 300°C provides optimum catalytic activity for CO oxidation.

关键词： 13X-type zeolite     CO oxidation     gold solution     pH     calcination temperature    

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Chemotactic effect of urokinase-type plasminogen activator on mouse spermatozoa

DING Xiaofang, LI Honggang, XIONG Chengliang

《医学前沿（英文）》 2008年 第2卷 第2期   页码 195-199 doi: 10.1007/s11684-008-0037-7

摘要： The aim of this study is to investigate the chemotactic effect of urokinase-type plasminogen activator (uPA) on mouse spermatozoa. Capillary assays were applied to study the chemotactic activity of ascending and descending gradients of uPA. Firstly, the chemotactic effect of an ascending gradient of uPA on mouse spermatozoa was observed by counting the number of spermatozoa that migrated into the capillary after incubation with uPA for 5, 10, 20, and 30 min, respectively, compared with that after incubation with F10. Twenty minutes was a suitable incubation time to obtain a plateau of sperm accumulation. Meanwhile, to confirm the specific effect of uPA on mouse sperm chemotaxis, uPA inhibitor (PAI-1) and anti-uPAR rabbit IgG were added to the test solution containing 20 U/mL uPA, respectively. To exclude the possibility that PAI-1 and anti-uPAR rabbit IgG may affect sperm accumulation nonspecifically, PAI-1 and anti-uPAR rabbit IgG were added to F10, respectively. It was found that the chemotactic effect of uPA was neutralized completely by PAI-1 and anti-uPAR rabbit IgG. PAI-1 and anti-uPAR rabbit IgG had no neutralizing effect on the sperm chemotactic effect. Lastly, the sperm chemotaxis response to a descending gradient of uPA was also observed. Taken together, the results suggest that uPA can induce sperm chemotaxis by binding to its receptor on the sperm membrane and may act as a chemoattractant in precontacting sperm-egg communication thereby increasing the chance encounter of spermatozoa and eggs.

关键词： chemotactic activity     receptor     uPA inhibitor     F10     chemoattractant    

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标题 作者 时间 类型 操作

A new method for the synthesis of molybdovanadophosphoric heteropoly acids and their catalytic activities

ZHANG Fumin, GUO Maiping, GE Hanqing, WANG Jun

期刊论文

Design and analysis of the gripper mechanism based on generalized parallel mechanisms with configurable moving platform

期刊论文

单自由度平面闭链机构构型方法的研究

张美麟,张晔,杨治义

期刊论文

New practice in semaglutide on type-2 diabetes and obesity: clinical evidence and expectation

期刊论文

Personalized medicine of type 2 diabetes

null

期刊论文

Immunological and virological characteristics of human immunodeficiency virus type 1 superinfection:

null

期刊论文

Automated synthesis of steady-state continuous processes using reinforcement learning

期刊论文

Metabolomics in human type 2 diabetes research

null

期刊论文

Correction to: Effect of wood dust type on mechanical properties, wear behavior, biodegradability, and

期刊论文

The mechanisms linking adiposopathy to type 2 diabetes

null

期刊论文

Mechanical performance analysis and stiffness test of a new type of suspension bridge

期刊论文

Targeted therapy of desmoid-type fibromatosis: mechanism, current situation, and future prospects

Zhen Wang, Jianhui Wu, Xiuyun Tian, Chunyi Hao

期刊论文

Development of an axial-type fan with an optimization method

Chong-hyun CHO, Soo-yong CHO, Chaesil KIM,

期刊论文

Low-temperature CO oxidation over Au-doped 13X-type zeolite catalysts: preparation and catalytic activity

Qing YE, Donghui LI, Jun ZHAO, Jiansheng ZHAO, Tianfang KANG, Shuiyuan CHENG

期刊论文

Chemotactic effect of urokinase-type plasminogen activator on mouse spermatozoa

DING Xiaofang, LI Honggang, XIONG Chengliang

期刊论文