Search Results

You are looking at 1 - 10 of 56 items for

  • Author: Xu Zhang x
Clear All Modify Search
Open access

Hailun Zhang and Sheng Xu

Abstract

The research measures the driving force of innovation in economic structure transition. In order to change the pattern of economic development, China is implementing a strategy of innovation-driven development. China’s capacity of innovation has been increasing, especially since 2012, and China’s innovations have taken a leap-forward development. Nowadays, innovation has become a main driving force in China’s economic development and hi-tech industries particularly make a great contribution. Although China’s tertiary industry has been dominant and its share in three industrial sectors has been exceeding 50% since 2015, a problem still exists in China’s economy that the proportions of primary and secondary industries are relatively higher compared with developed countries. In this paper we use PLSR model to measure the impact of innovation on China’s economic structure transition. It is found that innovation can expand the tertiary industry through shrinking the proportions of primary and secondary industries, transforming China’s economic structure into a more advanced pattern. Additionally, China is also devoting itself to the “Belt and Road Initiative”, which should be combined with China’s domestic innovation-driven development and realize sustainable development of economy worldwide.

Open access

Li Cong, Zhang Li, Zhang Guanqun, Xu Jianguo and Zhang Long

Abstract

The dissolution of corn stover in alkaline solvent system composed of NaOH-H2O2 was reported and the separation of its ingredients combined with acid precipitation, ethanol extraction was proposed. It is proven that the residual after alkali solvent was cellulose, the filtrate by the acid precipitation of the liquor was lignin, the solid by the ethanol extraction of the liquor was hemicellulose. The optimum dissolution conditions were determined by single-factor experiment as follows: the concentration of H2O2 5.0%, pH 11.5, dissolution temperature 60°C, dissolution time 3.0 h, the ratio of liquid to solid 30 mL/g. And chemical analysis were employed to determine the purity of the components separated. The structure of the components separated were identifi ed by FT-IR, SEM, XRD and NMR. The cellulose recovery yield can achieve to 84.2% and lignin recovery yield is 86.6%, the hemicellulose recovery yield is 96.7%. After recycling the solvent 3 times, the recovery yield of cellulose, lignin and hemicellulose were 82.7, 87.6 and 97.4%, and the purity of cellulose, lignin and hemicellulose were 98.0, 96.5 and 98.7%, respectively.

Open access

Yue-qiu Zhang, Shao-xia Xu, Sai-nan Bian, Li-fan Zhang, Yao Zhang, Wei-hong Zhang, Ying-chun Xu and Xiao-qing Liu

Abstract

Objective To investigate the infection rate of hepatitis C virus among the ambulatory patients and in-patients of a tertiary teaching hospital, and study the demographic factors related to the prevalence of hepatitis C virus infection.

Methods All patients tested for hepatitis C virus antibody from July 2008 to July 2009 in Peking Union Medical College Hospital were enrolled in this cross-sectional analysis. The prevalence of hepatitis C virus infection was compared according to age, gender, and departments, respectively. Among patients with positive serology hepatitis C virus marker, the positivity of hepatitis C virus RNA was analysed.

Results Among 29 896 subjects included, the hepatitis C virus antibody of 494 patients were positive (1.7%). When patients were divided into 9 age groups, the age specific prevalence of hepatitis C virus antibody were 0.2%, 1.7%, 1.2%, 1.1%, 1.5%, 1.9%,2.6%, 2.4% and 2%, respectively. The prevalence of hepatitis C virus antibody in non-surgical department and surgical department was 3% and 1%, respectively. The prevalence of hepatitis C virus antibody of males was higher than that of the females. Total of 194 patients with positive hepatitis C virus antibody were tested for hepatitis C virus RNA, the RNA level of 113 patients (58.2%) were higher than the low detection limit.

Conclusions The prevalence of hepatitis C virus antibody was relatively high among patients of general tertiary hospital. Age group of 60-69, males and patients in non-surgical departments were factors associated with high rate of hepatitis C virus infection.

Open access

Yuan Zhang, Michael Danikas, Xu Zhao and Yonghong Cheng

Preliminary Experimental Work on Nanocomposite Polymers: Small Partial Discharges at Inception Voltage, The Existence of Possible Charging Mechanisms Below Inception Voltage and the Problem of Definitions

In this paper, some results are presented from experiments concerning partial discharge (PD) behaviour of epoxy resin samples having 3 wt% nano- and 3 wt% micro-fillers, as well as epoxy samples having 3 wt%and1 wt% nanoparticles. The nano- and micro-fillers were TiO2 (titania). The main idea is to see whether a sample with PD at its inception voltage, still presents some tendency to charging effects below inception. An effort is being made to relate the present work with previous publications on the same main idea, as well as to previous research performed recently at Xian Jiaotong University, State Key Laboratory of Electrical Insulation and Power Equipment. It is indicated that with the samples investigated, although on some occasions random charging phenomena were observed below the inception voltage, it was not noted the same behaviour as with pure epoxy samples. Finally, a discussion ensues as to the definitions of the phenomena taking place below inception voltage.

Open access

Qijie Xu, Lei Zhang, Wenzhong Shi and Yuanchen Cui

Catalytic performances of cross-linking humic acids supported Pd/Ni bimetallic catalyst for heck reaction

The cross-linking humic acids (CL-HAs), epichlorohydrin as the cross-linking reagent and the supported Pd/Ni bimetallic catalysts (CL-HAs-Pd/Ni) were prepared and characterized by IR, AAS, XPS, TEM. The effects of reaction time, temperature, base, solvent and the amount of catalyst on the properties of the catalyst were studied. These catalysts could catalyze the Heck reaction of aryl halides and substituted aryl halides with acrylic acids or styrene successfully; the yields were all above 95%.

Open access

Qiuhong Sun, Junhai Zhang and Xinhang Xu

Abstract

This paper studies the characteristics of marine water quality monitoring data monitored by photoelectric sensor network, mines the potential information from the massive data. on account of the continuous accumulation of monitoring data, this paper focuses on the study of database with numerical attribute and proposes a rule updating algorithm for solving the rule maintenance issues caused by changes in the database. according to the rule, the algorithm forms a new database from part of the original data and the new data, and searches the new database by random search, thus can avoid creating a large number of redundant rules and can quickly mine effective rules at the same time. experimental results show that this method not only can avoid mining in the whole original massive data, but also can improve work efficiency, and can quickly and effectively find new data and find useful rules in the data with high practicability.

Open access

Linyu Gao, Yi Zhang, Liu Hong, Bingyang Xu, Yaoshuo Sang, Zhengyu Xu, Mingjian Zhang, Songjin Zheng, Xue Yun, Wenqi Li, Xiaoling Tang and Bin Li

Summary

In order to investigate the main factors behind hot coal fallout during cigarette smoking, an in-use behavior survey among smokers was conducted in three locations (Guiyang, Shijiazhuang and Nanchang) in China. In addition, a measuring device was designed to record whether a flicking or tapping force was exerted to remove ash and to record the force applied as well as their characteristic parameters. We found that there was no significant difference among the behavior characteristic parameters of the users in the three locations. The proportion of consumers who applied flicking was higher than the proportion of consumers tapping. There were some differences in the in-use behavior when smoking King Size and Superslim cigarettes. The work could help to develop a suitable hot coal fallout test method.

Open access

Qianqian Song, Wei Zhang, Fen Wu, Ningying Xu, Jinzhi Zhang, Mingshu Xu, Haihong Li, Zhujun Han and Haixia Gao

Abstract

The coding sequences (CDS) of TFAM and TFB2M genes from Jiaxing Black Pig (JBP) were first time obtained by RT-PCR and DNA-seq in the present study. Sequence analyses showed that the TFAM gene contains a 741-bp CDS region encoding 246 amino acids sharing a 100% homology with the sequence on NCBI, while TFB2M gene contains a CDS region of 1176 bp encoding 391 amino acids with two missense mutations. The results of quantitative Real-Time PCR for TFAM and TFB2M revealed that transcripts of the genes were both presented at highest levels in spleen tissue followed by liver tissue, while least levels in longissimus dorsi muscle (LDM), and obviously higher levels in two adipose tissues than those in LDM tissue(P<0.01). Meantime, a total of forty-two JBPs were employed in this experiment to investigate the effect of these two genes on the carcass, meat quality traits and flavor substances such as fatty acids, intramuscular fat (IMF) in LDM. With expectation, some strong correlations of gene expression abundance of TFAM and TFB2M mRNA in particular tissues such as liver and LDM with carcass and meat quality traits including marbling score, as well as the content of saturated fatty acid (SFA), in JBP were found.