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A Novel β-1,4-N, 6-O-Diacetylmuramidase from Streptomyces griseus and its Chemical Modification

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Chinese Chemical Letters 2006年第11期17卷 1469-1472页

作者： Chang Kui SUN yu zhen zhang Ming CHEN State Key Laboratory of Microbial Technology Shandong University Ji＇nan 250100

A novel lysozyme named β-1, 4-N, 6-O-diacetylmuramidase R2 was purified and characterized from Streptomyces griseus. The molecular weight of the enzyme was determined by MALDI-TOF-MS as 23.5 kDa. The N-terminal amino acid sequence was DTSGVQGIDVSHWQG. Chemical modification of β-1, 4-N, 6-O-diacetylmuramidase R2 indicated that sulfhydryl group and carbamidine of arginine residues are not essential for the activity of the enzyme, but lysine residues and imidazole of histidine residues are essential for the activity. The number of essential tryptophan and carboxyl groups was found that only one tryptophan residue and three carboxyl groups in the active site.

关键词： Chemical modification β-1 4-N 6-O-diacetylmuramidase lysozyme.

Development of a PC-based Open Architecture Software-CNC System

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Chinese Journal of Aeronautics 2007年第3期20卷 272-281页

作者： MA Xiong-bo HAN zhen-yu WANG Yong-zhang FU Hong-ya School of Electromechanical Engineering Harbin Institute of Technology Harbin 150001 China

As a key te..hnology in the field of advanced manufacturing, an open architecture controller is studied. In order to develop an open architecture software-CNC system on personal computer （PC） according to open modular architecture controllers （OMAC）. First, the software and hardware platform is chosen and software realization methodology for the CNC system is determined. Second, static modeling methods of an open architecture controller inclusive of object-oriented （OO） programming technology, dynamic link library （DLL） technology and system modules partition are investigated. Third, the dynamical behavioral modeling and the data flow representation of open architecture controller are discussed, which are both described in hierarchy fmite state machine （FSM） model. Fourth, a reusable software module model is established to develop software function module library. Finally, a 3-axis milling machine tool test-bed, named for HIT-CNC, is successfully designed by means of the constructed software function module library and the system configuring method. The experimental results show that, besides increasing the degree of reusability and openness, application of above-mentioned method- ology leads to significant decrease of development time as well as maintenance cost.

关键词： open architecture controller PC soflware-CNC behavioral model OMAC machine tool

Highly efficient photo-thermal synergistic catalysis of CO_(2)methanation over La_(1-x)Ce_(x)NiO_(3)perovskite-catalyst

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Nano Research 2024年第9期17卷 7945-7956页

作者： Ting Li zhen-yu zhang De-Cun Luo Bo-yu Xu Rong-Jiang zhang Ji-Long Yao Dan Li Tao Xie Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases ***,designing advanced photo-thermal catalysts remains a research challenge for CO_(2)methanation *** this work,a series of ABO3(A=lanthanide,B=transition metal)perovskite catalysts with Ce-substituted LaNiO3(La_(1-x)Ce_(x)NiO_(3),x=0,0.2,0.5,0.8,1)were synthesized for CO_(2)*** La_(0.2)Ce_(0.8)NiO_(3) exhibited the highest CH_(4) formation rate of 258.9 mmol·g^(-1)·hcat-1,CO_(2)conversion of 55.4%and 97.2%CH_(4) selectivity at 300℃with the light intensity of 2.9 W·cm^(-2).Then the catalysts were thoroughly analyzed by physicochemical structure and optical properties *** partial substitution of the A-site provided more active sites for the adsorption and activation of CO_(2)/H_(2).The sources of the active sites were considered to be the oxygen vacancies(O_(v))created by lattice distortions due to different species of ions(La^(3+),Ce^(4+),Ce^(3+))and exsolved Ni0 by H_(2)*** catalysts have excellent light absorption absorbance and low electron-hole(e^(-)/h^(+))recombination rate,which greatly contribute to the excellent performance in photo-thermal synergistic catalysis(PTC)CO_(2)*** results of in situ irradiated electron paramagnetic resonance spectrometer(ISI-EPR)and ISI-X-ray photoelectron spectroscopy(XPS)indicated that the aggregation of unpaired electrons near the defects and Ni metal(from La and Ce ions to Ov and Ni0)accelerated adsorption and activation of CO_(2)/H_(2).At last,the catalyst properties and structure were correlated with the proposed reaction mechanism from the in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)*** in situ precipitation of the B-site enhanced the dispersion of Ni,while its enriched photoelectrons upon illumination further promote hydrogen *** H^(*)spillover accelerated t

关键词： photo-thermal catalysis CO_(2)methanation perovskite A-site substitution in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)

Analysis of long non-coding RNA expression profiles in gastric cancer

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World Journal of Gastroenterology 2013年第23期19卷 3658-3664页

作者： Wei-Jun Cao Hai-Lu Wu Bang-Shun He yu-Shu zhang zhen-yu zhang Department of Gastroenterology Nanjing First Hospital Nanjing Medical University Central Laboratory Nanjing First HospitalNanjing Medical University

AIM: To investigate the expression patterns of long non-coding RNAs (lncRNAs) in gastric cancer. METHODS: Two publicly available human exon arrays for gastric cancer and data for the corresponding normal tissue were downloaded from the Gene Expression Omnibus (GEO). We re-annotated the probes of the human exon arrays and retained the probes uniquely mapping to lncRNAs at the gene level. LncRNA expression profiles were generated by using robust multi-array average method in affymetrix power tools. The normalized data were then analyzed with a Bioconductor package linear models for microarray data and genes with adjusted P -values below 0.01 were considered differentially expressed. An independent data set was used to validate the results. RESULTS: With the computational pipeline established to re-annotate over 6.5 million probes of the Affymetrix Human Exon 1.0 ST array, we identified 136053 probes uniquely mapping to lncRNAs at the gene level. These probes correspond to 9294 lncRNAs, covering nearly 76% of the GENCODE lncRNA data set. By analyzing GSE27342 consisting of 80 paired gastric cancer and normal adjacent tissue samples, we identified 88 lncRNAs that were differentially expressed in gastric cancer, some of which have been reported to play a role in cancer, such as LINC00152, taurine upregulated 1, urothelial cancer associated 1, Pvt1 oncogene, small nucleolar RNA host gene 1 and LINC00261. In the validation data set GSE33335, 59% of these differentially expressed lncRNAs showed significant expression changes (adjusted P -value < 0.01) with the same direction. CONCLUSION: We identified a set of lncRNAs differentially expressed in gastric cancer, providing useful information for discovery of new biomarkers and therapeutic targets in gastric cancer.

关键词： Long non-coding RNA Gastric cancer Microarray analysis Data mining

Indirect Spectrophotometric Determination of Sulphide with the Complex of Cd(Ⅱ)-5-Br-PADAP-CPB

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Chinese Chemical Letters 1997年第11期8卷 983-984页

作者： zhen yu zhang Wei An Liang(Department of Chemistry, Shandong University, Jinan 250100) Department of Chemistry Shandong University Jinan 250100 China

By the use of CPB, Cd(Ⅲ) forms a highly sensitive complex with 5-Br-PADAP in aqueous solution, molar absorptivity εis 1. 21 ×105 1. mol-1. *** amount of sulphide can be determined from its effect on the complex of Cd (Ⅲ)-5-Br-PADAP-CPB, sulphide in the range 0~3. 2 ×10-6mol dm-3 causes a decrease in absorption, that is a linear function of the concentration, For 13ng cm-3 sulphide, common metal ions such as Na+, K+, Ca2+, Mg2+, Al3+ and anions such as CO (24μg cm-3). S2O (22μg cm-3). PO (20μg cm-3) etc. do not interfere. A method for the indirect determination of sulphide in beer and in dustrial waste water with good selectivity and accuracy is described.

关键词： CPB Br-PADAP-CPB Indirect Spectrophotometric Determination of Sulphide with the Complex of Cd

Stabilizing and reinforcing effects of different fibers on asphalt mortar performance

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Petroleum Science 2015年第1期12卷 189-196页

作者： Meng-Meng Wu Rui Li yu-zhen zhang Liang Fan yu-Chao Lv Jian-Ming Wei State Key Laboratory of Heavy Oil Processing China University of Petroleum (East China)

Physical properties of different fibers （mineral, cellulose, or carbon fiber） and their stabilizing and reinforcing effects on asphalt mortar performance were studied. Scanning electron microscopy was used to study the effect of fiber＇s microstructure on asphalt mortar＇s performance. Laboratory tests of mesh-basket draindown and oven heating were designed and performed to evaluate the fibers＇ asphalt absorption and thermostability. A cone penetration test was used to study the flow resistance of fiber-modified asphalt mortar. Results showed that fiber can form a three-dimensional network structure in asphalt, and this network can be retained at high temperature. This network of fibers favors the formation of a thick coating of mastic without asphalt draining down. Cellulose fiber possessed a greater effect on asphalt absorption and sta- bilization than did the other fibers （mineral and carbon fiber）. A dynamic shear rheometer was used to evaluate their rheological properties and rut resistance. Results indicated that fiber can effectively improve the rut and flow resistance of asphalt mortar. However, the bending beam rheometer results demonstrated that the addition of fiber had negative effects on the creep stiffness and creep rate of asphalt mortar.

关键词： Fiber Asphalt mortar SEM Rheology Mechanical properties

Biochemical, molecular, and morphological variations of flight muscles before and after dispersal flight in a eusocial termite, Reticulitermes chinensis

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Insect Science 2021年第1期28卷 77-92页

作者： zhen-yu zhang Jing Ren Fei Chu Jun-Xia Guan Guang-yu Yang yu-Tong Liu Xin-Ying zhang Si-Qin Ge Qiu-Ying Huang Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina

Swarming behavior facilitates pair formation,and therefore mating,in many eusocial ***,the physiological adjustments and morphological transformations of the flight muscles involved in flying and flightless insect forms are still ***,we found that the dispersal flight of the eusocial termite Reticulitermes chinensis Snyder led to a gradual decrease in adenosine triphosphate supply from oxidative phospho・rylation,as well as a reduction in the activities of critical mitochondrial respiratory enzymes from preflight to ***,using three-dimensional reconstruction and transmission electron microscopy(TEM),the flight muscles were found to be gradually deteriorated during this *** particular,two tergo-pleural muscles(IItpm5 and IIItpm5)necessary to adjust the rotation of wings for wing shedding behavior were present only in flying *** findings suggest that flight muscle systems vary in function and morphology to facilitate the swarming flight procedure,which sheds light on the important role of swarming in successful extension and fecundity of eusocial termites.

关键词： dispersal flight eusocial termite flight muscle mitochondrial oxidative phosphorylation swarming behavior three-dimensional reconstruction

Enhanced CT and CT virtual endoscopy in diagnosis of heterotopic pancreas

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World Journal of Gastroenterology 2011年第33期17卷 3850-3855页

作者： Dan Wang Xiao-Er Wei Lei Yan yu-zhen zhang Wen-Bin Li Institute of Diagnostic and Interventional Radiology The Sixth Affiliated People＇s HospitalShanghai Jiao Tong UniversityShanghai 200233China

AIM:To improve the diagnosis of heterotopic pancreas by the use of contrastenhanced computed tomography(CT)imaging and CT virtual endoscopy(CTVE).METHODS:A total of six patients with heterotopic pancreas,as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University,Shanghai,China,were *** CT and enhanced CT scanning were performed,and the resulting images were reviewed and analyzed using threedimensional postprocessing software,including ***:Four males and two females were *** heterotopic pancreas sites were involved;three occurred in the stomach,including the gastric antrum(n =2)and lesser curvature(n=1),and two were in the duodenal *** one case of heterotopic pancreas lesion occurred in the *** cases had a solid yet soft tissue density that had a homogeneous pattern when viewed by enhanced ***,their CT values were similar to that of the *** ducts of the heterotopic pancreas tissue,one of the characteristic CT features of heterotopic pancreas tissue,were detected in the CT images of two *** images showed normal mucosa around the tissue,which is also an important indicator of a heterotopic ***,none of the CTVE images showed the typical signs of central dimpling or ***:CT,enhanced CT and CTVE techniques provide useful information about the location,growth pattern,vascularity,and condition of the gastrointestinal wall around heterotopic pancreatic tissue.

关键词： Heterotopic pancreas Computed tomography Contrast enhancement Computed tomography virtual endoscopy

Numerical and analytical investigations for the SOI LDMOS with alternated high-k dielectric and step doped silicon pillars

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Chinese Physics B 2020年第3期29卷 460-467页

作者： Jia-Fei Yao yu-Feng Guo zhen-yu zhang Ke-Meng Yang Mao-Lin zhang Tian Xia College of Electronic and Optical Engineering&College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210023China National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing 210023China School of Electrical Engineering University of VermontBurlingtonVT 05405USA

This paper presents a new silicon-on-insulator(SOI) lateral-double-diffused metal-oxide-semiconductor transistor(LDMOST) device with alternated high-k dielectric and step doped silicon pillars(HKSD device). Due to the modulation of step doping technology and high-k dielectric on the electric field and doped profile of each zone, the HKSD device shows a greater performance. The analytical models of the potential, electric field, optimal breakdown voltage, and optimal doped profile are derived. The analytical results and the simulated results are basically consistent, which confirms the proposed model suitable for the HKSD device. The potential and electric field modulation mechanism are investigated based on the simulation and analytical models. Furthermore, the influence of the parameters on the breakdown voltage(BV) and specific on-resistance(R_(on,sp)) are obtained. The results indicate that the HKSD device has a higher BV and lower R_(on,sp) compared to the SD device and HK device.

关键词： high-k dielectric step doped silicon pillar model breakdown voltage