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A plate-type port valve with rubber valve plate in a miniature diaphragm pump is presented. To investigate the dynamic characteristics of this type of discharge valve, a two-way fluid structure interaction model is proposed. The interaction between the dynamic behavior of the fluid and rubber is considered in the fluid structure interaction model. Based on the fluid structure interaction model, the internal flow of the pump, the deflection of the diaphragm and discharge valve plate is calculated. To verify the validity of the numerical model, a prototype pump is fabricated and tested. The experimental pressures in the working chamber of the pump show the same overall trends with the numerical results. The deviations between the numerical and experimental flowrates are less than 7.2%. The experimental results prove that the numerical model is effective in predicting a complete discharge process of the pump. There is a big difference between the deflection of the center of the valve plate and the edge of the valve plate. The oscillation period of the pressure in the working chamber of the pump is approximately double that of the discharge valve plate. When the pump speed is lower than 2500 r/min, it has little influence on the lag angles of the discharge valve under rated pressure. The lag angles at rated pump speed increase when the backpressures increase. The stress of the discharge valve plate reaches a peak when the valve plate impact on the valve limiter or valve seat. [ABSTRACT FROM AUTHOR]

5.2 HT ht 13 HT ht Based on Eq. (1), the maximum sin I i SB I b i sb can be obtained when HT ht . 15 HT ht. [Extracted from the article]

Selective catalytic reduction is the main technology to reduce oxides of nitrogen of diesel exhaust. As an important part of the selective catalytic reduction system, the air-assisted urea dosing system regulates the flow rate by adjusting the pump speed, and the flow rate and its metering accuracy directly affect the efficiency of oxides of nitrogen conversion. A mathematical model coupled with the air-assisted urea dosing system and the suction pipeline was built, and the influences of the discharge pressure, pump speed, suction pipeline length, and diameter on the flow characteristics and metering accuracy of the air-assisted urea dosing system were analyzed. The flow rate and metering accuracy of a prototype of the air-assisted urea dosing system were tested under different conditions on a test rig. Results show that the flow stability and metering accuracy of the prototype elevate with increasing the discharge pressure when the prototype has no overfeeding, and it gets down under any discharge pressure when the prototype occurs overfeeding. The flow stability and metering accuracy of the prototype improve with increasing the pump speed, and increase significantly when the suction pipeline length becomes shorter and the diameter gets larger. The metering accuracy of the prototype can achieve to ±2% by optimizing the suction pipeline parameters. The experimental results prove that the proposed mathematical model is effective. [ABSTRACT FROM AUTHOR]

Unless the targeted mesh is developable, metric distortion is inevitable during the process of surface mesh parameterization, thus one important objective of all involved parametric studies is to reduce the metric distortion. In order to further reduce area and angle distortion, a novel method of boundary-free mesh parameterization is presented in the paper. Firstly, the initial boundary-fixed conformal parameterization from 3D surface mesh patch to a plane is performed in the method. Then, based on the initial parameterization, the iterations of boundary-free quasi-harmonic parameterization are developed, where the tensor field is updated in each iterative step and the principal curvature direction is utilized to terminate the iteration. The solution of the novel method is convenient to calculate since it involves a series of linear systems. In our novel parameterization method, lower metric distortion and considerable efficiency have been obtained in experiments. [ABSTRACT FROM AUTHOR]

Fabrication of non‐noble metal‐based heterogeneous catalysts by a facile and cost‐effective strategy for ecofriendly catalytic transfer hydrogenation (CTH) is of great significance for organic transformations. A cobalt@nitrogen‐doped carbon (Co@NC) catalyst was prepared from renewable biomass‐derived sucrose, harmless melamine, and earth‐abundant Co(AcO)2 as the precursor materials by hydrothermal treatment and carbonization. Co nanoparticles (NPs) were coated with NC shells and uniformly embedded in the NC framework. The as‐obtained Co@NC‐600 (carbonized at 600 °C) catalyst exhibited excellent catalytic efficiency for CTH of various functionalized nitroarenes with formic acid (FA) as hydrogen donor in aqueous solution. The uniformly incorporated N atoms in the C matrix and the encapsulated Co NPs showed synergistic effects in the CTH reactions. A mechanistic analysis indicated that the protons from FA were activated by Co sites after being captured by N atoms, and then reacted with nitroarenes adsorbed on the surface of the catalysts to generate the corresponding aromatic amines. Moreover, the catalyst showed excellent durability and reusability without obvious decrease in activity even after five reaction cycles. Thus, the study reported herein provides a cost‐effective, sustainable strategy for fabrication of biomass‐derived non‐noble metal‐based catalysts for green and efficient catalytic transformations. Give it some sugar: A cobalt nanoparticles@nitrogen‐doped carbon (Co@NC) catalyst is prepared from biomass‐derived sucrose, ecofriendly melamine, and earth‐abundant Co(AcO)2. The Co@NC catalyst exhibits excellent catalytic efficiency for catalytic transfer hydrogenation (CTH) of various functionalized nitroarenes with formic acid as hydrogen donor in aqueous solution [ABSTRACT FROM AUTHOR]

Essential proteins as a vital part of maintaining the cells’ life play an important role in the study of biology and drug design. With the generation of large amounts of biological data related to essential proteins, an increasing number of computational methods have been proposed. Different from the methods which adopt a single machine learning method or an ensemble machine learning method, this paper proposes a predicting framework named by XGBFEMF for identifying essential proteins, which includes a SUB-EXPAND-SHRINK method for constructing the composite features with original features and obtaining the better subset of features for essential protein prediction, and also includes a model fusion method for getting a more effective prediction model. We carry out experiments on Yeast data to assess the performance of the XGBFEMF with ROC analysis, accuracy analysis, and top analysis. Meanwhile, we set up experiments on E. coli data for the validation of performance. The test results show that the XGBFEMF framework can effectively improve many essential indicators. In addition, we analyze each step in the XGBFEMF framework; our results show that both each step of the SUB-EXPAND-SHRINK method as well as the step of multi-model fusion can improve prediction performance. [ABSTRACT FROM AUTHOR]

This article investigates the impact of trade liberalization on trade patterns, firm markups, and firm locations in a two-factor monopolistic competition model that features variable elasticity of substitution by a general additively separable utility. We find that, depending on the relative export hurdles, either direction of one-way trade may occur when trade opens up. Its direction determines the responses of firm-level markups and various home market effects to falling trade costs. Our results show that some important findings in the literature are robust only with particular classes of preferences. We provide a possible rationale for some well-known conflicting empirical facts. [ABSTRACT FROM AUTHOR]

Despite recent legislation and regulations to protect homeowners’ rights in the process of urbanization, forced eviction remains one of the most prevalent causes of violence in contemporary China. This article examines the capacity of residents of Chinese cities to protect their property rights using new media to produce alternative discourses on law in the urbanization process. Fieldwork conducted in Beijing from 2007 to 2008, a period during which the national capital underwent massive development schemes for the 2008 Summer Olympic Games, shows that homeowners create virtual precedents, backed not by the authority of the court, but by that of the media. Evictees of so-called dingzihu (nail-houses) facing chaiqian (demolition and relocation) develop arguments based on the 2007 case of Wu Ping, the first new media superstar in (post-)socialist China. The article, following post-structuralist formulations, develops a theory of ‘legal surrealism’ characteristic of the position of law in reform-era China. Whereas social media is equated with revolution elsewhere, in China, the lesson of the role of new media in effecting social change may be one of limitation. While digital mass communication technologies may assist individual ‘victories’, challenges to eviction face both intrinsic and extrinsic obstacles for collective action. [ABSTRACT FROM PUBLISHER]

To further open up China's banking, insurance, securities and auto financing markets was one of the commitments China made on accession to the World Trade Organization in December 2001. By examining China's implementation of these commitments in the past few years and the reform of China's law and regulations in banking, insurance, securities and auto financing, this article attempts to explore, first, some of the issues raised in the WTO annual transitional reviews of China's implementation, second, the economic impacts that the reform of China's financial services law and regulations has brought about, and third, future reforms of China's financial services law and regulations. The discussion includes different views from scholars and commentators and covers the approach taken by the Chinese government and financial regulators. The article points out that future reform of China's financial services law and regulations depends upon, on the one hand, China's continuous implementation of its WTO commitments and, on the other, the reforms in such other areas as foreign exchange, taxation, and the personal credit information network. [ABSTRACT FROM AUTHOR]

Some inflammatory biomarkers are associated with the post-surgical prognosis in cancer patients. However, their clinical importance in gallbladder cancer has rarely been explored. The aim of this study is to assess the efficacy of surgical intervention and the effectiveness of preoperative test on neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and monocyte-to-lymphocyte ratio (MLR) for predicting the prognosis in gallbladder cancer patients. In this study, a total of 255 gallbladder cancer patients were retrospectively selected. For each patient, we recorded his/her treatment algorithm (with or without surgery) and their preoperative inflammatory biomarkers, as well as their detailed survival information for 5 years. A total of 216 patients received surgical intervention and the other 39 chose conservative treatment. The median survival time was 4.6 months for non-surgical group (P < 0.001), and 12.2 months for surgical intervention group. Among the surgical group, ROC analysis showed the AUC of NLR, PLR and MLR were 0.675 (95% CI: 0.600 to 0.751, P < 0.001), 0.599 (95% CI: 0.520 to 0.677, P = 0.017) and 0.607 (95% CI: 0.529 to 0.686, P = 0.009), respectively. In conclusion, surgical intervention did improve the overall survival, and elevated NLR and MLR before surgery are associated with shorter OS of GBC patients. [ABSTRACT FROM AUTHOR]

The safety of vascular closure devices (VCDs) is still debated. The emergence of more related randomized controlled trials (RCTs) and newer VCDs makes it necessary to further evaluate the safety of VCDs. Relevant RCTs were identified by searching PubMed, EMBASE, Google Scholar and the Cochrane Central Register of Controlled Trials electronic databases updated in December 2014. Traditional and network meta-analyses were conducted to evaluate the rate of combined adverse vascular events (CAVEs) and haematomas by calculating the risk ratios and 95% confidence intervals. Forty RCTs including 16868 patients were included. Traditional meta-analysis demonstrated that there was no significant difference in the rate of CAVEs between all the VCDs and manual compression (MC). Subgroup analysis showed that FemoSeal and VCDs reported after the year 2005 reduced CAVEs. Moreover, the use of VCDs reduced the risk of haematomas compared with MC. Network meta-analysis showed that AngioSeal, which might be the best VCD among all the included VCDs, was associated with reduced rates of both CAVE and haematomas compared with MC. In conclusion, the use of VCDs is associated with a decreased risk of haematomas, and FemoSeal and AngioSeal appears to be better than MC for reducing the rate of CAVEs. [ABSTRACT FROM AUTHOR]