检索结果-南通市图书馆

干湿循环下地聚合物固化黄土强度劣化机制与模型研究

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

岩土力学 2022年第5期43卷 1164-1174页

作者：陈锐张星郝若愚包卫星长安大学公路学院陕西西安710064

采用地聚合物对黄土进行固化处理,通过三轴试验研究了干湿循环下不同掺量地聚合物固化黄土抗剪强度的劣化规律,提出了固化土强度劣化的经验公式。结合X射线衍射(X-ray diffraction,简称XRD)、电镜扫描(scanning electron microscopy,简... 详细信息

采用地聚合物对黄土进行固化处理,通过三轴试验研究了干湿循环下不同掺量地聚合物固化黄土抗剪强度的劣化规律,提出了固化土强度劣化的经验公式。结合X射线衍射(X-ray diffraction,简称XRD)、电镜扫描(scanning electron microscopy,简称SEM)和压汞(mercury intrusion porosimetry,简称MIP)试验,分析了水化产物、固化土微观形貌演化与孔隙分布,探讨了地聚合物固化黄土的劣化机制。三轴试验结果表明:相较于素土,固化土的抗剪强度随地聚合物掺量增加而显著提高,黏聚力及内摩擦角最高提升260%和43%;固化土抗剪强度与孔隙率η对地聚合物体积含量G_(v)的比值η/G_(v)呈幂函数关系;地聚合物可有效提高固化土的抗干湿耐久性,在9次干湿循环后10%和15%的地聚合物固化土抗剪强度仍保持初始强度的75%以上,但5%的地聚合物固化土在干湿作用下劣化明显,经历9次干湿循环后其强度接近素土;干湿循环对固化土峰值偏应力与黏聚力影响较大,对内摩擦角影响较小。综合考虑地聚合物掺量、围压及干湿循环次数的影响,提出了地聚合物固化土强度劣化经验公式并验证了其准确性。XRD、SEM和MIP试验结果表明:地聚合物的主要水化产物是水化硅酸钙(calcium silicate hydrate,简称CSH)和水化硅铝酸钙(calcium aluminosilicate hydrate,简称CASH),其胶结和充填作用增强土体黏聚力并使土体形成致密的微观结构,从而提高固化土的强度;干湿循环使得土体孔隙扩张并产生新裂隙,导致土颗粒间的胶结破坏,进而劣化固化土宏观强度。

关键词：黄土地聚合物干湿循环强度劣化固化机制预测模型

Simultaneous determination of tyrosine and dopamine in urine samples using excitation-emission matrix fluorescence coupled with second-order calibration

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2013年第3期24卷 239-242页

作者： Shan-Shan Li hai-Long Wu Ya-Juan Liu Hui-Wen Gu Ru-Qin yu State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan University

A ＂green＂ and quick analytical method for complex compounds was developed for simultaneous determination of tyrosine （Tyr） and dopamine （DA） in urine samples in this paper. The three-way responsive data recorded by excitation-emission matrix fluorescence （EEM） spectrometer was analyzed using second-order calibration methods based on both parallel factor analysis （PARAFAC） and self- weighted alternating trilinear decomposition （SWATLD） algorithms. The EEM spectra of the analytes were overlapped with the background in urine samples. However the second-order advantage of both PARAFAC and SWATLD methods was exploited, even in the presence of unknown interferences and the satisfactory results can be obtained. Furthermore, the linear ranges of Tyr and DA were determined to be 0.042-6.42 p.g/mL and 0.18-4.43/ug]mL, respectively, and the accuracies of both methods were validated by the analytical figures of merit （FOM）.

关键词： Second-order calibrationPARAFACSWATLDTyrosineDopamine

Identification and Genetic Analysis of a Novel Rice Spotted-Leaf Mutant with Broad-Spectrum Resistance to Xanthomonas oryzae pv. oryzae

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2014年第4期13卷 713-721页

作者： SHEN hai-chao SHI Yong-feng FENG bao-hua WANG Hui-mei XU Xia HUANG Qi-na Lü Xiang-guang WU Jian-li State Key Laboratory of Rice Biology China National Rice Research Institute

A spotted-leaf mutant of rice HM143 was isolated from an EMS-induced IR64 mutant bank. Brown lesions randomly distributed on leaf blades were observed about 3 wk after sowing. The symptom lasted for the whole plant growth duration. Histochemical analysis indicated that cell death occurred in and around the site of necrotic lesions accompanied with accumulation of hydrogen hyperoxide. Agronomic traits were largely similar to the wild type IR64 except seed setting rate and 1 000-grain weight which were significantly decreased in the mutant. Disease resistance of the mutant to multiple races of Xanthomonas oryzae pv. oryzae was significantly enhanced. Genetic analysis showed that the mutation was controlled by a single recessive gene, tentatively termed splHM143. In addition, using molecular markers and 1023 mutant type individuals from an F2 segregating population derived from the cross HM143/R9308, the spotted-leaf gene was finally delimited to an interval of 149 kb between markers XX25 and ID40 on the long arm of chromosome 4. splHM143 is likely a novel rice spotted-leaf gene since no other similar genes have been identified near the chromosomal region.

关键词： rice spotted-leaf mutant hypersensitive response-like bacterial blight resistance molecular marker

Regulation of Migration, Phagocytosis and Apoptosis of Human Neutrophils by Recombinant Human Intestinal Alkaline Phosphatase

在线全文

学校读者我要写书评

暂无评论

Journal of Northeast Agricultural University(English Edition) 2022年第4期29卷 50-61页

作者： Hui Mi-zhou Cong Zhen-yu Jia Xiao-xiao Guo Tian-tian Wu Shu-yin Shuang bao School of Life Sciences Northeast Agricultural UniversityHarbin 150030China School of Animal Technology Sciences Qingdao Agricultural UniversityQingdao 266109China School of Food Sciences Northeast Agricultural UniversityHarbin 150030China

The purpose of this study was to explore the effects of recombinant human intestinal alkaline phosphatase(recIAP) on human neutrophils in vitro, and the migration, phagocytosis, apoptosis in presence and absence of LPS. In this study, freshly extracted human neutrophils were used to establish an inflammatory cell model, and the control group, recIAP group, LPS group and recIAP +LPS group were set up to stimulate the model. The migration of neutrophils was detected by agarose gel drop method. Fluorescent particles and fluorescent probes were added to different treatment groups, and the phagocytic rate of neutrophils and the release of reactive oxygen species(ROS) from neutrophils were detected by flow cytometry. The apoptosis rate of neutrophils was detected by flow cytometry according to Annexin V-FITC apoptosis detection kit. The results showed that regardless of the presence or absence of LPS, recIAP could inhibit the migration of neutrophils, phagocytosis and the release of ROS. In addition, recIAP could weaken the inhibitory effect of LPS on neutrophils apoptosis.

关键词： alkaline phosphatase migration phagocytosis apoptosis reactive oxygen species(ROS)

Analysis of Gram-positive bacterial infection in patients following liver transplantation

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2012年第14期125卷 2417-2421页

作者： LI Hong yu De-lei REN lei ZHONG Lin PENG Zhi-hai TENG Mu-jian Department of Hepatobiliary Surgery Qianfoshan HospitalAffiliated to Shandong University Jinan Shandong 250014 China Shandong University School of Medicine Jinan Shandong250061 China Department of Hepatobiliary Surgery Affiliated First People'sHospital Shanghai Jiao Tong University Shanghai 200080 China

Background Liver transplantation is the most effective treatment for patients with end-stage liver failure, however infection after transplantation is a serious clinical complication. The purpose of this research was to investigate the molecular epidemiology and the influence of multidrug-resistant Gram-positive infection in patients, following liver transplantation, to provide reference for clinical treatment and prevention of Gram-positive bacterial infection. Methods We isolated and detected bacteria from phlegm, throat swabs, urine, wound or wound secretions, blood, and fecal samples from 221 liver transplant patients in our hospital from January 2007 to April 2010. All isolated bacterial strains were identified and tested by minimal inhibitory concentration （MIC） drug-sensitive detection using the BioMerieux ATB bacterial identification instrument and repetitive extragenic palindromic-polymerase chain reaction （REP-PCR） detection of bacterial homology. Risk factors were calculated by multivariate Logistic regression analysis. Results We collected 250 specimens from 221 patients hospitalized following liver transplantation surgery, of which 29 patients developed multiple infections. Sixty-five Gram-positive bacterial strains were isolated from different specimens from 53 infectious patients. We detected 29 multidrug-resistant Gram-positive strains from 29 patients （44.62%）, including 20 Staphylococcus aureus （S. aureus） strains （68.97%） and nine Enterococcus strains （31.03%）. All 20 S. aureus strains were highly resistant to aminoglycosides （gentamicin）, cephalosporins （cefoxitin）, quinolones （ciprofloxacin and levofloxacin）, lincomycins （clindamycin）, penicillin, and erythromycin. The resistance rate reached 100% in some cases. The S. aureus strains were highly sensitive to vancomycin and oxazolidinone （linezolid）, with MIC50 〈2 pg/ml for both. The nine Enterococci strains were also highly resistant to aminoglycosides, quinolones, and penicillins, and highly se

关键词： Gram-positive bacillus,liver transplantation, molecular epidemiology risk factors

Role of coxsackievirus and adenovirus receptor in the pathogenesis of dilated cardiomyopathy and its influencing factor

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2008年第15期121卷 1445-1449页

作者： ZHANG Shuo JIA hai-bo GONG Bin-sheng ZHANG Shao-jun LI Xia yu Bo Department of Cardiology Second Affiliated Hospital Harbin Medical University Harbin Heilongjiang 150086 China College of Bioinformatics Science and Technology and Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State Harbin Medical University Harbin Heilongjiang 150081 China

Background Although clinical treatment for heart failure and sudden death has been improved over the last few decades, the morbidity and mortality of dilated cardiomyopathy （DCM） have increased. So a better understanding of the underlying molecular events leading to DCM is urgent. Persistent viral infection （especially coxsackievirus group B3） of the myocardium in viral myocarditis and DCM has never been neglected by experts. Recent data indicate that the up-regulation of coxsackievirus and adenovirus receptor （CAR） in viral cardiomyopathy contributes to viral infection as a key factor in the pathogenesis of this disease. This study aimed to investigate the role and regulatory mechanism of CAR in DCM by the bioinformatic method. Methods We identified the clusters of genes co-expressed with CAR by clustering algorithm based on the public available microarray dataset of DCM （Kittleson, et al. 2005）, and mapped these genes into the protein-protein interaction networks to investigate the interaction relationship to each other at the protein level after confirming that the samples are characterized by the cluster of genes in correctly partitioning. Results The gene cluster GENESET 11 containing 33 genes including CAR with similar expression pattern was identified by cluster algorithm, of which 19 genes were found to have interaction information of the protein encoded by them in the current human protein interaction database. Especially, 12 genes present as critical nodes （called HUB node） at the protein level are involved in energy metabolism, signal transduction, viral infection, immuno-response, cell apoptosis, cell proliferation, tissue repair, etc. Conclusions The genes in GENESET 11 together with CAR may play a pathogenic role in the development of DCM, mainly involved in the mechanism of energy metabolism, signal transduction, viral infection, immuno-response, cell apoptosis and tissue repair.

关键词： dilated cardiomyopathy viral receptor protein interaction gene cluster bicluster

Preparation and characterization of conducting polymer-coated thermally expandable microspheres

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2017年第3期28卷 658-662页

作者： Shu-Ying Chen Zhi-Cheng Sun Lu-hai Li Yong-Hao Xiao Yan-Min yu Beijing Engineering Research Center of Printed Electronics School of Printing and Packaging Engineering Beijing Institute of Graphic Communication College of Environmental & Energy Engineering Beijing University of Technology

The thermally expandable microspheres（TEMs） were prepared via suspension polymerization with acrylonitrile（AN）, methyl methacrylate（MMA） and methyl acrylate（MA） as monomers and n-hexane as the blowing agent. Meanwhile, a novel type of functional and conductive thermal expandable microsphere was obtained through strongly covering the surface of microsphere by conductive polymers with the mass loading of 1.5%. The optimal conditions to prepare high foaming ratio and equally distributed microcapsules were investigated with AN-MMA-MA in the proportion of 70%/20%/10%（m/m/m）, and 25 wt% of n-hexane in oil phase. The further investigation results showed that the unexpanded TEMs were about 30 μm in diameter and the maximum expansion ratio was nearly 125 times of original volume. The polypyrrole（PPy） was smoothly coated on the surface of the TEMs and the expansion property of PPy-coated TEMs was almost the same as the uncoated TEMs. Moreover, the structure and expanding performance of TEMs and PPy-coated TEMs were characterized by scanning electron microscopy（SEM）, laser particle size analyzer and dilatometer（DIL）.

关键词： Thermally expandable microspheres Suspension polymerization Conducting polymer Preparation Characterization Particle size

Inhibition of Nogo expression to promote repair after spinal cord injury

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2012年第22期125卷 4044-4048页

作者： SUN Hong-hui GAO Feng LIU Bin yu hai-tao KONG Ning LIU Guo-min Jilin Univ Hosp 2 Dept Orthoped Changchun 130041 Jinlin Peoples R China Jilin Univ Hosp 2 Dept Gen Surg Changchun 130041 Jinlin Peoples R China Jilin Univ Coll Pharm Dept Regenerat Med Changchun 130041 Jinlin Peoples R China

Background One of the reasons for poor neuroregeneration after central nervous system injury is the presence of inhibitory factors such as Nogo. Here, we tested the inhibition of Nogo by RNA interference both in vitro and in vivo, using recombinant adenovirus-mediated transfection of short hairpin RNAs, to explore a new method of treatment for spinal cord injury. Methods We designed and cloned two Nogo-specific short hairpin RNAs and an unrelated short hairpin RNA, packaged the clones into adenovirus, and amplified the recombinant virus in 293 cells. We then tested the inhibition of Nogo expression both in vitro in adenovirus-transfected oligodendrocytes and in vivo in spinal cord tissue from adenovirus-transfected spinal cord injury model rats. We tested Nogo expression at the mRNA level by reverse-transcription PCR and at the protein level by Western blotting and immunohistochemistry. Results In vitro, the two specific Nogo short hairpin RNAs decreased Nogo mRNA expression by 51% and 49%, respectively, compared with Nogo expression in cells transfected with the unrelated control small hairpin RNA （P 〈0.005）. Similarly, Nogo protein expression decreased by 50% and 48%, respectively （P 〈0.005）. In vivo, in spinal cord injury model rats, the two specific Nogo short hairpin RNAs decreased Nogo mRNA expression by 45% and 40%, respectively, compared with Nogo expression in spinal cord injury model rats transfected with the unrelated control short hairpin RNA （P 〈0.005）. The Nogo protein level was similarly decreased. Conclusions We were successful in specifically downregulating Nogo at the mRNA and protein levels by adenovirus-mediated delivery of short hairpin RNAs, both in vitro and in vivo. This confirms the effectiveness of RNA interference for the inhibition of Nogo gene expression and the efficiency of using adenovirus for delivery. Thus gene therapy may be an effective treatment for spinal cord injury.

关键词： spinal cord injury axonal regeneration RNA interference short hairpin RNA

THE DISTRIBUTION OF THE ORDER PARAMETER IN JOSEPHSON TUNNELLING JUNCTION

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1985年第4期2卷 181-184页

作者： ZHANG yu-heng LIU Hong-bao CHEN Geng-hua Department of Physics University of Science and Technology of ChinaHefei Institute of Physics Academia SinicaBeijing

The distribution of the order parameter in a Josephson junction has been investigated *** are upper and lower critical thicknesses d_(c) and d_(m) in a Josephson *** tunnelling junction is a normal superconductor when... 详细信息

关键词： junction. Josephson superconductor