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Chinese Journal of Polymer Science 2023年第11期41卷 1714-1724,I0006页

作者： Chang-Tong Song xian-hong zhang Dong Chen Yu-hong Ma Wan-Tai Yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Without any type of su rfactant or dispersing agent,precipitation polymerization has great superiorities in both polymer synthesis and *** the present work,the polymerization of vinyl chloride(VC),n-butyl acrylate(BA),and vinyl acetate(VAc)are conducted in the precipitation polymerization system and series of their random terpolymers poly(vinyl chloride-co-n-butyl acrylate-co-vinyl acetate)(PCBV)are synthesized *** effects of various polymerization conditions,including solvent polarity,temperature,initiator concentration,and monomer feed ratios on the polymerization kinetics,number-average molecular weight(M_(n)),and terpolymer composition are investigated *** solvent and the monomer feed ratio are crucial factors not only for the polymer morphology,but also for the reaction *** the non-polar solvent such as n-hexane,the PCBV displays particle morphology when the composition of BA ratio lower than 10 wt%.Otherwise,the PCBV forms a uniform polymer phase and precipitates out from the *** the polar solvent,e.g.,dimethyl carbonate(DMC)and ethanol,the PCBV polymer maintains a slurry state either in low or in high monomer feed ***,VC based ternary copolymer that obtained in n-hexane has much lower M_(n)(40 wt%)compared with emulsion and suspension ***,the terpolymer can be easily sepa rated by simple centrifugation.

关键词： Precipitation polymerization Copolymerization Vinyl chloride Low molecular weight

Preparation of Ultralow Molecular Weight Poly(vinyl chloride) with Submicrometer Particles via Precipitation Polymerization

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Chinese Journal of Polymer Science 2019年第7期37卷 646-653页

作者： Peng Cui Chang-Tong Song xian-hong zhang Dong Chen Yu-hong Ma Wan-Tai Yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Poly(vinyl chloride), with ultralow molecular weight, produced by free radical polymerization either at high temperature or in the presence of chain transfer agents, is widely used as special resins and polymer process additives. This paper reports a new process, called self-stabilized precipitation polymerization, in which the polymerization of vinyl chloride monomer (VCM) is conducted in hydrocarbon diluents without addition of any suspending agent or emulsifier. The merits of this novel strategy include:(1) PVC resins with ultra-low number-average molecular weight (Mn) from 4000 to 15000, which is much lower than Mn of those prepared by conventional suspension and emulsion polymerizations,(2) sub-micrometer PVC particles with near spherical morphology, and (3) the very simple post-polymerization separation process. Under mild stirring, polymerization proceeds stably and smoothly. The influences of main process factors, such as solvents, initiator and monomer concentrations, polymerization time, and temperature on both particle morphology and Mn of the polymer products are investigated systematically. The molar ratio of-CH2-CHCl-/-CH=CH-CH2CHCl, a good indicator of structural defects, is about 1000/0.1 which means the low molecular weights do not result from chain transfer to the monomers. Then the mechanism of this polymerization is proposed. In summary, this novel polymerization technology provides a straightforward method for preparing PVC particulate products with low Mn.

关键词： Precipitation polymerization Vinyl chloride Ultralow molecular weight Pure product

A Rapid Solid-phase Synthesis to Soluble Oligothiophene Molecular Wires

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Chinese Chemical Letters 2006年第4期17卷 437-440页

作者： hong Ming zhang xian hong WANG Xiao Jiang ZHAO Ji LI Fo Song WANG Polymer Material Engineering Lab Changchun Institute of Applied Chemistry CAS Changchun 130022

A novel method for the preparation of oligothiophene molecular wires is described via a bi-directional solid-phase synthesis. Using an alternating sequence of bromination and Stille coupling reactions, oligomers were ... 详细信息

关键词： Solid-phase synthesis molecular wires oligothiophene.

Regulation of anti-Mullerian hormone(AMH)in males and the associations of serum AMH with the disorders of male fertility

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Asian Journal of Andrology 2019年第2期21卷 109-114页

作者： Hui-Yu Xu hong-xian zhang Zhen Xiao Jie Qiao Rong Li Center for Reproductive Medicine Department of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China Key Laboratory of Assisted Reproduction Ministry of EducationBeijing 100191China National Clinical Research Center for Obstetrics and Gynecology Beijing 100191China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing 100191China Department of Urology Peking University Third HospitalBeijing 100191China Department of Reproductive Endocrinology Zhejiang Provincial People's HospitalHangzhou Medical CollegeHangzhou 310014China

Anti-Mullerian hormone(AMH)is a functional marker of fetal Sertoli *** germ cell number in adults depends on the number of Sertoli cells produced duri ng peri natal *** ntly,AMH has received increasi ng attenti on in research of disorders related to male *** paper reviews and summarizes the articles on the regulation of AMH in males and the serum levels of AMH in male fertility-related *** have determined that follicle-stimulating hormone(FSH)promotes AMH transcription in the absenee of androgen *** inhibits the transcriptional activation of *** undetectable levels of serum AMH and testosterone levels indicate a lack of functional testicular tissue,for example,that in patients with anorchia or severe Klinefelter syndrome suffering from impaired *** normal serum testosterone level and undetectable AMH are highly suggestive of persistent Mullerian duct syndrome(PMDS),combined with clinical *** levels of both AMH and testosterone are always subnormal in patients with mixed disorders of sex development(DSD).Mixed DSD is an early-onset complete type of disorder with fetal hypogonadism resulting from the dysfunction of both Leydig and Sertoli *** AMH levels are varying in patients with male fertility-related disorders,in cludi ng pubertal delay,severe con genital hypog on adotropic hypogonadism,nonobstructive azoospermia,Klinefelter syndrome,varicocele,McCune-Albright syndrome,and male senescence.

关键词： anti-Mullerian hormone disorders related to male fertility follicle-stimulating hormone testosterone

Establishing the lower limits of total serum testosterone among Chinese proven fertile men who received treatment of assisted reproductive technology

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Asian Journal of Andrology 2020年第4期22卷 396-400页

作者： Hui-Yu Xu Hui Jiang Guo-Shuang Feng Ying Feng Yong Han Wen-Hao Tang hong-xian zhang Feng-Hua Chen hong-Xia zhang De-Feng Liu Rong Li Jie Qiao Center for Reproductive Medicine Department of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China Key Laboratory of Assisted Reproduction(Peking University) Ministry of EducationBeijing 100191China National Clinical Research Center for Obstetrics and Gynecology Beijing 100191China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing 100191China Department of Urology Peking University Third HospitalBeijing 100191China Center for Clinical Epidemiology and Evidence-Based Medicine Beijing Children's Hospital Capital Medical UniversityNational Center for Children's HealthBeijing 100045China Clinical Research Institute Zhejiang Provincial People's HospitalHangzhou 310014China

Testosterone(T)plays a crucial role in spermatogenesis because extremely low levels of intratesticular T lead to correspondingly low serum levels of total T(tT),severe disorders of spermatogenesis,and male ***,there is little consensus on the lower limits of serum tT in proven fertile men undergoing assisted reproductive technology treatments in Chinese or other Asian *** aimed to establish the reference range of serum tT based on a population of 868 fertile Chinese men undergoing in vitro fertilization or intracytoplasmic sperm injection and embryo transfer(IVF/ICSI-ET)*** defined a fertile man as having had a live baby with his partner as recorded in our IVF registration *** lower limits of serum tT were established using a Siemens IMMULITE 2000 chemiluminescent *** 1st,2.5th,and 5th percentiles and their 95%confidence intervals(CIs)were 3.6(95%CI:2.7–4.1)nmol l−1,4.3(95%CI:4.1–5.0)nmol l−1,and 5.6(95%CI:4.8–5.8)nmol l−1,*** the linear correlation of serum tT between the Siemens platform and a liquid chromatography–tandem mass spectrometry platform,the calculated lower limits of serum tT were also established for fertile Chinese men undergoing IVF/ICSI-ET treatments,which will benefit the clinical diagnosis and treatment of male infertility during such procedures.

关键词： chemiluminescence fertile men in vitro fertilization or intracytoplasmic sperm injection and embryo transfer liquid chromatography-tandem mass spectrometry lower reference limits serum total T

Traumatic Diaphragmatic Hernia Associated with Pelvic Ring Fracture

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Chinese Medical Journal 2015年第9期128卷 1272-1274页

作者： Yin zhang Tao Cheng hong Gao xian-Long zhang Department of Orthopedic Shanghai Jiao Tong University Affliated Sixth People@s Hospital Shanghai 200233 China

Traumatic diaphragmatic hernia （TDH） is an uncommon injury and a marker of severe *** injury is rarely associated with pelvic ring fracture,although TDH is one of the most dangerous comorbidities of such *** this condition is easily misdiagnosed in emergency cases,we reported two cases and analyzed the clinical symptoms,diagnosis,treatment,and outcome of this *** on these results,we recommended an appropriate method for diagnosis and treatment and proposed a contraindication in treating TDH associated with pelvic fracture.

关键词： Emergency Injury Control Pelvic Ring Fracture Pelvic Straps Traumatic Diaphragmatic

The Number and Distributions of Limit Cycles of a Cubic Hamiltonian System with Z_2-symmetry Perturbation

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Chinese Quarterly Journal of Mathematics 2011年第1期26卷 144-151页

作者： ZHOU hong-xian zhang Yan School of Mathematical Sciences Xuchang UniversityXuchang 461000China

This paper is concerned with the number and distributions of limit cycles of a cubic Z2-symmetry Hamiltonian system under quintic *** using qualitative analysis of differential equation,bifurcation theory of dynamical systems and the method of detection function,we obtain that this system exists at least 14 limit cycles with the distribution C91  [C11 ＋ 2（C32 2C12）].

关键词： limit cycles bifurcation detection functions Hamiltonian system

Surgical complexity and prognostic outcome of small volume renal cell carcinoma with high-level venous tumor thrombus and large volume renal cell carcinoma with low-level thrombus

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Chinese Medical Journal 2019年第15期132卷 1780-1787页

作者： Zhuo Liu Xun Zhao hong-xian zhang Li-Wei Li Shi-Ying Tang Guo-Liang Wang Shu-Dong zhang Shu-Min Wang Lu-Lin Ma Xiao-Jun Tian Department of Urology Peking University Third Hospital Beijing 100191 China Department of Ultrasound Peking University Third Hospital Beijing 100191 China

Background:Radical nephrectomy with thrombectomy is one of the most difficult and complicated urological *** the roles of renal tumor volume and thrombus level in surgical complexity and prognostic outcome are not *** study aimed to evaluate the surgical complexity and prognostic outcome between the volume of renal cell carcinoma (RCC) and the level of venous tumor ***:The clinical data of 67 RCC cases with renal vein or inferior vena cava (IVC) tumor thrombus from January 2015 to May 2018 were retrospectively *** these 67 cases,21 (31.3%) were small tumors with high-level thrombus (tumor ≤7 cm in diameter and thrombus Neves Level Ⅱ-Ⅳ),while 46 (68.7%) were large tumors with low-level thrombus group (tumor >7 cm in diameter and thrombus Level 0-Ⅰ).Clinical features,operation details,and pathology data were *** and multivariable logistic regression analyses were applied to evaluate the risk factors for small tumor with high-level ***:Patients with small tumors and high-level thrombus were more likely to have longer operative time (421.9 ± 135.1 min vs.282.2 ± 101.9 min,t=4.685,P < 0.001),more surgical bleeding volume (1200 [325,2900] mL vs.500 [180,1000] mL,U =270.000,P =0.004),more surgical blood transfusion volume (800 [0,1400] mL vs.0 [0,800] mL,U =287.500,P =0.004),more plasma transfusion volume (0 [0,800] mL vs.0 [0,0] mL,U =319.000,P =0.004),higher percentage of open operative approach (76.2% vs.32.6%,x2 =11.015,P =0.001),higher percentage of IVC resection (33.3% vs.0%,x2 =17.122,P < 0.001),and higher percentage of post-operative complications (52.4% vs.19.6%,x2 =7.415,P =0.010) than patients with large tumors and low-level *** multivariate analysis,decreased hemoglobin (Hb)(odds ratio [OR]:0.956,95 % confidence interval [CI]:0.926-0.986,P =0.005) and non-sarcomatoid differentiation (OR:0.050,95% CI:0.004-0.664,P =0.023) were more likely to form small tumors with high-level tumor t

关键词： Inferior vena cava Tumor thrombus Renal cell carcinoma Cancer-specific survival Prognosis Neves classification

Peking University Third Hospital score:a comprehensive system to predict intra-operative blood loss in radical nephrectomy and thrombectomy

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Chinese Medical Journal 2020年第10期133卷 1166-1174页

作者： Zhuo Liu Xun Zhao hong-xian zhang Run-Zhuo Ma Li-Wei Li Shi-Ying Tang Guo-Liang Wang Shu-Dong zhang Shu-Min Wang Xiao-Jun Tian Lu-Lin Ma departm ent of Urology Peking University Third HospitalBeijing 100191China Health Science Center Peking UniversityBeijing 100191China Department of Ultrasound Peking University Third HospitalBeijing 100191China.

Background:Radical nephrectomy and thrombectomy is the standard surgical procedure for the treatment of renal cell carcinoma (RCC) with tumor thrombus (TT). But the estimation of intra-operative blood loss is only based on the surgeon’s experience. Therefore, our study aimed to develop Peking University Third Hospital score (PKUTH score) for the prediction of intra-operative blood loss volume in radical nephrectomy and ***: The clinical data of 153 cases of renal mass with renal vein (RV) or inferior vena cava tumor thrombus admitted to Department of Urology, Peking University Third Hospital from January 2015 to May 2018 were retrospectively analyzed. The total amount of blood loss during operation is equal to the amount of blood sucked out by the aspirator plus the amount of blood in the blood-soaked gauze. Univariate linear analysis was used to analyze risk factors for intra-operative blood loss, then significant factors were included in subsequent multivariable linear regression ***: The final multivariable model included the following three factors: open operative approach (P < 0.001), Neves classification IV (P < 0.001), inferior vena cava resection (P = 0.001). The PKUTH score (0-3) was calculated according to the number of aforementioned risk factors. A significant increase of blood loss was noticed along with higher risk score. The estimated median blood loss from PKUTH score 0 to 3 was 280 mL (interquartile range [IQR] 100-600 mL), 1250 mL (IQR 575-2700 mL), 2000 mL (IQR 1250-2900 mL), and 5000 mL (IQR 4250-8000 mL), respectively. Meanwhile, the higher PKUTH score was, the more chance of post-operative complications (P = 0.004) occurred. A tendency but not significant overall survival difference was found between PKUTH risk score 0vs. 1 to 3 (P = 0.098).Conclusion: We present a structured and quantitative scoring system, PKUTH score, to predict intra-operative blood loss volume in radical nephrectomy and thrombectomy.

关键词： Renal cell carcinoma Venous thrombosis Blood loss Inferior vena cava

SEM Studies on Vessels in Selaginella

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SEM Studies on Vessels in Selaginella