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Rotational Isomeric State Model of Poly(vinylidene chloride) Based Upon ab Initio Electronic Structure Calculations

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Chemical Research in Chinese Universities 2009年第1期25卷 108-111页

作者： ZHANG zhi-jie liu yu-hua Lü Zhong-yuan LI Ze-sheng Institute of Theoretical Chemistry State Key Laboratory of Theoretical and Computational Chemistry Jilin University Changchun 130021 P. R. China

The rotational isomeric state（RIS） model was constructed for poly（vinylidene chloride）（PVDC） based on quantum chemistry calculations. The statistical weighted parameters were obtained from RIS representations and ab initio energies of conformers for model molecules 2,2,4,4-tetrachloropentane（TCP） and 2,2,4,4,6, 6-hexachloroheptane（HCH）. By employing the RIS method, the characteristic ratio C∞ was calculated for PVDC. The calculated characteristic ratio for PVDC is in good agreement with experiment result. Additionally, we studied the influence of the statistical weighted parameters on C∞ by calculating δC∞/δlnw. According to the values of δC∞/δlnw, the effects of second-order Cl-CH2 pentane type interaction and C1--C1 long range interaction on C∞ were found to be important. In contrast, first-order interaction is unimportant.

关键词： Ab initio calculations Characteristic ratio Poly(vinylidene chloride)

Immunohistochemical analysis of PD-L1 and tumor-infiltrating immune cells expression in the tumor microenvironment of primary signet ring cell carcinoma of the prostate

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Asian Journal of Andrology 2022年第5期24卷 525-532页

作者： Qi-Liang Teng Xin-Rui Yang Shuang Wen zhi-Hong Dai Hong-Long Wang Tian-Qing liu Liang Wang Bo Fan zhi-yu liu Department of Urology Second Affiliated Hospital of Dalian Medical UniversityDalian 116023China Department of Clinical Imaging Second Affiliated Hospital of Dalian Medical UniversityDalian 116023China Department of Pathology Dalian Friendship HospitalDalian 116001China

Primary signet ring cell carcinoma(SRCC)of the prostate is a rare ***,its potential tumorigenic mechanism,clinicopathological features,and prognostic outcome have not been systematically *** determine the pathogenic mechanism,we detected distributions of programmed cell death-ligand 1(PD-L1),programmed death 1(PD-1),and cellular components in the tumor microenvironment,including tumor-infiltrating lymphocytes(CD4 and CD8),tumor-associated macrophages(TAMs;CD163 and CD68),and tumor-associated fibroblasts(vimentin and alpha-smooth muscle actin[α-SMA]),in tumor tissues from four patients with primary prostatic SRCC compared with corresponding adjacent tissues and tumor tissues from 30 patients with prostate adenocarcinoma(PCa)by immunohistochemical *** found higher expression of PD-L1,CD163,and CD68 in primary SRCC specimens than that in both corresponding adjacent nontumor specimens and PCa specimens with different Gleason scores,indicating that TAMs may participate in the malignant biological behavior of primary SRCC of the *** further analysis,we searched electronic journal databases and Surveillance,Epidemiology,and End Results(SEER)to identify 200 eligible patients including our four *** to Kaplan–Meier survival curve analysis,patients<68 years old,with radical prostatectomy(RP),Gleason score of 7–8,and lower clinical stage had longer overall survival(OS).Moreover,Cox multivariate analysis indicated that race(hazard ratio[HR]=1.422),surgical approach(HR=1.654),and Gleason score(HR=2.162)were independent prognostic factors for ***,primary SRCC of the prostate represents a distinct and aggressive subtype of prostate cancer associated with a higher distribution of PD-L1 and TAMs,which warrants further clinical investigation.

关键词： clinical features immunohistochemistry infiltrating immune cells primary signet ring cell carcinoma of the prostate tumor microenvironment

Use of packed-fiber solid-phase extraction for sample clean-up and preconcentration of vitamin B_(12) before determination

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Chinese Chemical Letters 2009年第12期20卷 1491-1494页

作者： Fang Fang Xue Jun Kang zhi Yong liu yu Qin Ma Zhong Ze GU State Key Laboratory of Bioelectronics Southeast University Nanjing 210096 China

A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitamin functional drink. The analysis used a reversed-phase C18 column, with a photo-diode array detector at 220 nm. The samples were preconcentrated with packed-fiber solid-phase extraction columns. Good linearity was observed in vitamin functional drink. The repeatability of extraction performance, expressed as relative standard deviations, was from 3.5% to 4.3%. The limit of detection （LOD） is 5 ng mL^-1 （S/N = 3）. Finally, the method had been applied for the determination of vitamin B12 in vitamin functional drink.

关键词： Vitamin B12 Nanofibers Packed-fiber solid-phase extraction Preconcentration

TURBULENT MIXING AND EVOLUTION IN A STABLY STRATIFIED FLOW WITH A TEMPERATURE STEP

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Journal of Hydrodynamics 2009年第1期21卷 84-92页

作者： QIU Xiang ZHANG Dao-xiang LU zhi-ming liu yu-lu Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Department of Mathematics Shanghai University Shanghai 200444 China

Large-Eddy Simulation （LES） is applied to examine the turbulent mixing and evolution in a stably stratified flow with a thermally sharp interface. Turbulent velocity intensities and turbulent kinetic energy are analyzed by considering the mean shear and stratification effects. The evolution of turbulent mixing layer and turbulent structures are mainly investigated. The results show that the streamwise intensities are much larger than the vertical intensities, and vertical fluctuations decay more rapidly at the presence of stratification. The qualitatively computational results suggest that the mixing layer, defined by the mean temperature, inclines to the side with small inlet velocity. The evolution of the half-width of the mixing layer shows two different slopes. The turbulent structure with high vorticity is restricted in the mixing layer especially in strong stratified cases.

关键词： stratified turbulence turbulent mixing turbulent structure Large-Eddy Simulation (LES)

A nested case-control study of maternal-neonatal transmission of hepatitis B virus in a Chinese population

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World Journal of Gastroenterology 2011年第31期17卷 3640-3644页

作者： Li-Zhang Chen Wen-Qi Zhou Shu-Shan Zhao zhi-yu liu Shi-Wu Wen School of Public Health Central South UniversityChangsha 410078Hunan ProvinceChina Eight-Year Program Xiangya School of MedicineCentral South University410008 ChangshaHunan ProvinceChina Maternal and Child Health Hospital of Hunan Province Changsha 410008Hunan ProvinceChina The OMNI Research Group Department of Obstetrics and GynecologyUniversity of Ottawa501 Smyth RoadBox 241Ottawa K1H 8L6Canada Ottawa Health Research Institute Clinical Epidemiology Program Canada Department of Epidemiology and Community Medicine University of OttawaK1H 8L6Canada

AIM:To examine the determinants of maternal-neonatal transmission of hepatitis B virus(HBV) METHODS:A nested case-control study was conducted in Changsha,Hunan,People's Republic of China from January 1,2005 to September 31,2006 To avoid potential maternal blood contamination,we collected vein blood of newborns immediately after birth and before initial hepatitis B vaccination to determine the HBV infection status of the newborn For each HBsAg-positive infant,one HBsAg-negative infant born to an HBsAg-positive mother was matched by hospital at birth(same),gender(same),and date of birth(within 1 mo) A faceto-face interview was conducted to collect clinical and epidemiological data Conditional logistic regression analysis was used to estimate the independent effects of various determinants on maternal-neonatal transmission of HBV RESULTS:A total of 141 HBsAg-positive infants and 141 individually matched HBsAg-negative infants were included in the final analysis Maternal first-degree family history of HBV infection,intrahepatic cholestasis,and premature rupture of membranes were risk factors for perinatal transmission of HBV,whereas systematic treatment and HBV immunoglobulin injections for mothers with HBV infection were protective factors for maternal-neonatal transmission of HBV,after adjustment for potential confounding factors CONCLUSION:For HBsAg-positive mothers,systematic treatment,HBV immunoglobulin administration,and controlling intrahepatic cholestasis and pregnancy complications may reduce the incidence of perinatal transmission of HBV.

关键词： HBsAg-positive Hepatitis B virus Perinatal transmission:Nested case-control study

The enhancement of performance and imbibition effect of slickwater-based fracturing fluid by using MoS_(2)nanosheets

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Petroleum Science 2023年第4期20卷 2187-2201页

作者： Hang Xu yuan Li Guo-Lin yu Sa-Sa Yang Bo-Jun Li Fu-Jian Zhou Er-Dong Yao Hao Bai zhi-yu liu Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing102249China National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Slickwater-based fracturing fluid has recently garnered significant attention as the major fluid for volumetric fracturing;however,lots of challenges and limitations such as low viscosity,poor salt tolerance,and possible formation damage hinder the application of the conventional simple slickwater-based fracturing *** addition,nanomaterials have proven to be potential solutions or improvements to a number of challenges associated with the *** this paper,molybdenum disulfide(MoS_(2))nanosheets were chemically synthesized by hydrothermal method and applied to improve the performance of conventional slickwater-based fracturing ***,the microstructure characteristics and crystal type of the MoS_(2)nanosheets were analyzed by SEM,EDS,TEM,XPS,and Raman spectroscopy ***,a series of evaluation experiments were carried out to compare the performance of MoS_(2)nanosheet-modified slickwater with the conventional slickwater,including rheology,drag reduction,and sand ***,the enhanced imbibition capacity and potential mechanism of the nanosheet-modified slickwater were systematically *** results showed that the self-synthesized MoS_(2)nanosheets displayed a distinct ultrathin flake-like morphology and a lateral size in the range of tens of *** the nano-composites,each MoS_(2)nanosheet plays the role of cross-linking point,so as to make the spatial structure of the entire system more ***,nanosheet-modified slickwater demonstrates more excellent properties in rheology,drag reduction,and sand *** nanosheet-modified slickwater has a higher apparent viscosity after shearing 120 min under 90℃ and 170 s^(−1).The maximum drag reduction rate achieved 76.3%at 20℃,and the sand settling time of proppants with different mesh in the nano-composites was *** imbibition experiments showed that the gel-breaking fluid of nanosheet-modified slickwater exhibited excellent capability of

关键词： Slickwater-based fracturing fluid MoS_(2)nanosheet Performance evaluation spontaneous imbibition Climbing film

Emodin ameliorates lipopolysaccharides-induced corneal inflammation in rats

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International Journal of Ophthalmology(English edition) 2015年第4期8卷 665-669页

作者： Guo-Ling Chen Jing-Jing Zhang Xin Kao Lu-Wan Wei zhi-yu liu Department of Ophthalmology the Second Hospital of Shandong University Department of Ophthalmology the Third People's Hospital of Jinan Department of Anatomy Shandong Univeristy School of Medicine

· AIM: To investigate the effect of emodin on pseudomonas aeruginosa lipopolysaccharides(LPS)-induced corneal inflammation in rats.· METHODS: Corneal infection was induced by pseudomonas aeruginosa LPS in Wistar rats. The inflammation induced by LPS were examined by slit lamp microscope and cytological checkup of aqueous *** tissue structure was observed by hematoxylin and eosin(HE) staining. The activation of nuclear factor kappa B(NF-κB) was determined by Western *** ribonucleic acid(m RNA) of tumor necrosis factor-α(TNF-α) and intercellular adhesion molecule-1(ICAM-1) in LPS-challenged rat corneas were measured with reverse transcription-polymerase chain reaction(RT-PCR).· RESULTS: Typical manifestations of acute corneal inflammation were observed in LPS-induce rat model,and the corneal inflammatory response and structure were improved in rats pretreated with emodin. Treatment with emodin could improve corneal structure, reduce corneal injure by reducing corneal inflammatory response. Emodin could inhibit the decreasing lever of inhibitor of kappa B alpha(IкBα) express, and the m RNA expression of TNF-α and ICAM-1 in corneal tissues was also inhibited by emodin. The differences were statistically significant between groups treated with emodin and those without treatment(P <0.01).·CONCLUSION: Emodin could ameliorate LPS-induced corneal inflammation, which might via inhibiting the activation of NF-κB.

关键词： nuclear factor kappa B inhibitor alpha therapy inflammation

NATURAL PRODUCTS SYNTHESIS BY RETRO-DIELS-ALDER REACTION Ⅱ~1 ASYMMETRIC SYNTHESIS OF (+) AND (-) 5-OXO-ENDO-TRICYCLO [5.2.1.0.^(2, 6)] DECA-3, 8-DIENE 1 BY ENZYME-CATALYZED REACTION

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Chinese Chemical Letters 1992年第10期3卷 787-788页

作者： Lian ZHANG Ji Ying YANG zhi yu liu Shanghai Institute of Oganic Chemistry Chinese Academy of sciences345 Lingling LuShanghai 200032

Asymmetric syntheses of both enantiomerically pure (+) and (-) 5-oxo-endo-tricyclo [5.***.1.0.^(2,6)] deca-3, 8-diene 1 was described. The key step is the use of enzyme-catalyzed hydrolysis of meso-diacetate 5.

关键词： OXO-ENDO-TRICYCLO NATURAL PRODUCTS SYNTHESIS BY RETRO-DIELS-ALDER REACTION ASYMMETRIC SYNTHESIS OF DECA-3 DIENE 1 BY ENZYME-CATALYZED REACTION AND

The structural elucidation of two new artificial steroidal saponins

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Chinese Chemical Letters 2012年第3期23卷 332-334页

作者： Bin Wu zhi yu liu Ming Song Fan Zhao Lin Sun Wei Xin Jiang Cheng Gang Huang Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203China Harbin University of Commerce Harbin 150076China

Two novel steroidal saponins（timosaponin BⅢ-a,timosaponin BⅢ-b） together with a known steroidal saponin（timosaponin BⅡ-b） were prepared by the dilute acid hydrolysis of timosaponin BⅢ.Their structures were elu... 详细信息

关键词： Rhizoma anemarrhenae Steroidal saponin Timosaponin BⅢ Acid hydrolysis NMR