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Observations of nitrous acid and its relative humidity dependence in Shanghai 被引量:9
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作者 HAO Nan ZHOU Bin CHEN Dan CHEN Li-min 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期910-915,共6页
Nitrous acid, HNO2, is an important precursor of OH radicals in the troposphere. Measurements of HNO2 and NO2, using differential optical absorption spectroscopy (DOAS), were performed in Shanghai, China for a perio... Nitrous acid, HNO2, is an important precursor of OH radicals in the troposphere. Measurements of HNO2 and NO2, using differential optical absorption spectroscopy (DOAS), were performed in Shanghai, China for a period from October 22, 2004 to January 4, 2005. The mean (and median) hourly concentrations of HNO2 and NO2 during this period were 1.1 (0.7) ppb and 24 (21.4) ppb respectively. A correlation between HNO2/NO2 and PM10 mass concentrations was obtained. This correlation suggests that significant heterogeneous chemical production of HNO2 may occur through NO2 reactions on aerosol surfaces. This hypothesis was further supported by detailed analysis of selected pollution episodes in this study. At the same time, the water dependence of HNO2 formation was studied by analysis of relative humidity (RH). It showed that the maximum HNO2/NO2 ratio was increased along with RH below 70% and inhibited at RH〉70%. 展开更多
关键词 DOAS heterogeneous formation nitrous acid PM o aerosol relative humidity
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HA@Fe_(3)O_(4)修饰阳极增强微生物燃料电池降解类固醇雌激素
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作者 王昌鲁 余厂 +3 位作者 黄斌 来超超 郭子维 潘学军 《精细化工》 EI CAS CSCD 北大核心 2024年第1期166-173,194,共9页
利用腐植酸(HA)与具有较强电容性的纳米Fe_(3)O_(4)颗粒形成的金属化合物(HA@Fe_(3)O_(4))修饰微生物燃料电池(MFC)阳极,探究含有以17α-乙炔基雌二醇(EE2)为代表性类固醇雌激素(SEs)的模拟废水在MFC阳极的降解特性,并对EE2降解过程中MF... 利用腐植酸(HA)与具有较强电容性的纳米Fe_(3)O_(4)颗粒形成的金属化合物(HA@Fe_(3)O_(4))修饰微生物燃料电池(MFC)阳极,探究含有以17α-乙炔基雌二醇(EE2)为代表性类固醇雌激素(SEs)的模拟废水在MFC阳极的降解特性,并对EE2降解过程中MFC的产电特性进行了表征。电化学交流阻抗测试结果表明,与不存在HA@Fe_(3)O_(4)的MFC相比,存在HA@Fe_(3)O_(4)的MFC的欧姆阻抗降低了79.58%,电荷转移阻抗降低了89.60%。循环伏安扫描结果显示,HA@Fe_(3)O_(4)的存在显著增加了阳极板的电容。HA@Fe_(3)O_(4)修饰阳极后MFC最大功率密度可达537.37 mW/m~2。HA@Fe_(3)O_(4)修饰的阳极可显著提高MFC对EE2的去除率,EE2在低浓度下(≤5.0μmol/L)可以介导电子转移,提高MFC的产电性能,进而提高MFC去除EE2的能力,但高浓度(5.0~10.0μmol/L)时会抑制微生物的活性并降低MFC产电效率。 展开更多
关键词 腐植酸 燃料电池 17Α-乙炔基雌二醇 ha@Fe_(3)O_(4) 生物膜 厌氧 水处理技术
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Response of Tomato Sugar and Acid Metabolism and Fruit Quality under Different High Temperature and Relative Humidity Conditions 被引量:1
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作者 Yanjiao Zheng Zaiqiang Yang +1 位作者 Tingting Wei Heli Zhao 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第9期2033-2054,共22页
The combined stress of high temperature and high relative air humidity is one of the most serious agrometeorological disasters that restricts the production capacity of protected agriculture.However,there is little in... The combined stress of high temperature and high relative air humidity is one of the most serious agrometeorological disasters that restricts the production capacity of protected agriculture.However,there is little information about the precise interaction between them on tomato fruit quality.The objectives of this study were to explore the effects of the combined stress of high temperature and relative humidity on the sugar and acid metabolism and fruit quality of tomato fruits,and to determine the best relative air humidity for fruit quality under high temperature environments.Four temperature treatments(32℃,35℃,38℃,41℃),three relative air humidity(50%,70%,90%)and four duration(3,6,9,12 d)orthogonal experiments were conducted,with 28℃,50%as control.The results showed that under high temperature and relative air humidity,the activity of sucrose metabolizing enzymes in young tomato fruits changed,which reduced fruits soluble sugar content;in addition,enzyme activities involved phosphopyruvate carboxylase(PEPC),mitochondria aconitase(MDH)and citrate synthetase(CS)increased which increased the content of organic acids(especially malic acid).Eventually,vitamin C,total sugar and sugar-acid ratio decreased significantly,while the titratable acid increased,resulting in a decrease in fruit flavor quality and nutritional quality in ripe fruit.Specifically,a temperature of 32℃and a relative air humidity of 70%were the best cultivation conditions for tomato reproductive growth period under high temperature.Our results indicating that fruit quality reduced under high temperature at the flowering stage,while increasing the relative air humidity to 70%could alleviate this negative effect.Our results are benefit to better understand the interaction between microclimate parameters under specific climatic conditions in the greenhouse environment and their impact on tomato flavor quality. 展开更多
关键词 Heat stress relative air humidity organic acid metabolism fruit flavor quality TOMATO
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Fractal analysis of polyferric chloride-humic acid(PFC-HA) flocs in different topological spaces 被引量:9
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作者 WANG Yili LU Jia +2 位作者 DU Baiyu SHI Baoyou WANG Dongsheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第1期41-48,共8页
The fractal dimensions in different topological spaces of polyferric chloride-humic acid (PFC-HA) flocs, formed in flocculating different kinds of humic acids (HA) water at different initial pH (9.0, 7.0, 5.0) a... The fractal dimensions in different topological spaces of polyferric chloride-humic acid (PFC-HA) flocs, formed in flocculating different kinds of humic acids (HA) water at different initial pH (9.0, 7.0, 5.0) and PFC dosages, were calculated by effective densitymaximum diameter, image analysis, and N2 absorption-desorption methods, respectively. The mass fractal dimensions (De) of PFC-HA floes were calculated by bi-logarithm relation of effective density with maximum diameter and Logan empirical equation. The Df value was more than 2.0 at initial pH of 7,0, which was 11% and 13% higher than those at pH 9.0 and 5.0, respecively, indicating the most compact flocs formed in flocculated HA water at initial pH of 7.0. The image analysis for those flocs indicates that after flocculating the HA water at initial pH greater than 7.0 with PFC flocculant, the fractal dimensions of D2 (logA vs. logdL) and D3 (logVsphere vs. logdL) of PFC-HA floes decreased with the increase of PFC dosages, and PFC-HA floes showed a gradually looser structure. At the optimum dosage of PFC, the D2 (logA vs. logdL) values of the flocs show 14%-43% difference with their corresponding Dr, and they even had different tendency with the change of initial pH values. However, the D2 values of the floes formed at three different initial pH in HA solution had a same tendency with the corresponding Df. Based on fractal Frenkel-Halsey-HiU (FHH) adsorption and desorption equations, the pore surface fractal dimensions (Ds) for dried powders of PFC-HA flocs formed in HA water with initial pH 9.0 and 7.0 were all close to 2.9421, and the Ds values of flocs formed at initial pH 5.0 were less than 2.3746. It indicated that the pore surface fractal dimensions of PFC-HA floes dried powder mainly show the irregularity from the mesopore-size distribution and marcopore-size distribution. 展开更多
关键词 polyferric chloride-humic acid (PFC-ha flocs topological spaces fractal dimensions effective density image analysis pore surface fractal
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A Novel Thin Film Resistive Humidity Sensor Based on SolubleConjugated Polymer:(propionic acid)-co-(propargyl alcohol)
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作者 Yang LI Mu Jie YANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第8期701-702,共2页
A novel soluble conjugated copolymer (propionic acid)-co-(propargyl alcohol) (PA-co-OHP) has been synthesized for the first time using a new palladium acetylide catalyst Pd(PPh3)(2)(C=CC(CH3)(2)OH)(2)(PPB). Thin film ... A novel soluble conjugated copolymer (propionic acid)-co-(propargyl alcohol) (PA-co-OHP) has been synthesized for the first time using a new palladium acetylide catalyst Pd(PPh3)(2)(C=CC(CH3)(2)OH)(2)(PPB). Thin film resistive humidity sensor based oil the copolymer doped with HClO4 was prepared. The impedance of the sensor changed from 10(3)similar to 10(7) Omega in 95%similar to 30%RH, and the response of that is very quick (<6 sec.). Preliminary results show the copolymer is a promising humidity sensitive material. 展开更多
关键词 humidity sensor conjugated polymer propiolinc acid propargyl alcohol
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Use of High-Resolution Ultrasound (HRU) in the Assessment of Deep Injections of CHAP-Hyaluronic Acid (CHAP-HA) Fillers for Midface Lift 被引量:1
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作者 Hsiao-Tung Lee Haw-Yueh Thong 《Journal of Cosmetics, Dermatological Sciences and Applications》 2018年第3期126-132,共7页
High-resolution ultrasound (HRU) imaging is a useful tool to study hyaluronic acid (HA) filler injection in the face. It is noninvasive, quick, well-tolerated, and can provide in vivo and dynamic information. The form... High-resolution ultrasound (HRU) imaging is a useful tool to study hyaluronic acid (HA) filler injection in the face. It is noninvasive, quick, well-tolerated, and can provide in vivo and dynamic information. The formations of pools or pearls in HA fillers could be observed real time during injection. The plane of injection could be determined accurately, and there were no specimen manipulation artifacts. It was observed that HA gel fillers with differing production technologies showed distinct spread and distribution patterns in the periocular tissues on HRU examination. The authors used HRU to assess deep injections of CHAP-Hyaluronic Acid (CHAP-HA) fillers for midface lift. 10 patients who underwent bilateral midface deep injections using CHAP-HA filler were examined with HRU before and immediately after treatment, and in 2 weeks and one month later. The CHAP-HA appeared as hypoechoic densities within the preperiosteal plane in HRU. CHAP-HA adopted variable morphology within the tissue depending on individual tissue densities and the compliance of the tissues in the plane of injection. CHAP-HA was unidentifiable with surrounding tissue after one month in 13 of the 20 injection sites. HRU allows in vivo study of CHAP-HA injection behavior and could be a tool for further studies of HA-tissue reactions. 展开更多
关键词 ChaP-Hyaluronic acid (ChaP-ha) FILLER High-Resolution Ultrasound (HRU) MIDFACE Lift DEEP INJECTIONS Preperiosteal FILLER INJECTIONS
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流体剪切力下CD44-HA介导的MDA-MB-231细胞及HL60细胞的滚动黏附 被引量:1
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作者 张颖 方颖 +2 位作者 吴建华 林余 马琳琳 《医用生物力学》 CAS CSCD 北大核心 2023年第2期220-227,共8页
目的探究胞外基质中的透明质酸(hyaluronic acid,HA)如何调控血流中CD44+肿瘤细胞的黏附滚动行为。方法采用平行平板流动腔装置,观察记录流场中MDA-MB-231细胞及HL60细胞在固定HA上的运动,提取细胞滚动黏附特征参数。结果MDA-MB-231细胞... 目的探究胞外基质中的透明质酸(hyaluronic acid,HA)如何调控血流中CD44+肿瘤细胞的黏附滚动行为。方法采用平行平板流动腔装置,观察记录流场中MDA-MB-231细胞及HL60细胞在固定HA上的运动,提取细胞滚动黏附特征参数。结果MDA-MB-231细胞在HA底板上的黏附受到HA浓度的正向调控,但不受HA分子量影响;与物理吸附相比,生物素-亲和素固定的HA可显著提高细胞的黏附比率。在30~50 mPa剪切力范围内,剪切力的增加加快了细胞的滚动速度,降低了细胞的黏附比率,但对细胞的栓缚时间影响不大。同样流场中,与MDAMB-231细胞比较,CD44表达水平较低的HL60细胞在HA底板上的栓缚时间短、滚动速度快、黏附比率低(<1.5%)。结论流体剪切力可能通过调节CD44-HA的结合速率而非解离速率来调控MDA-MB-231细胞的滚动速度;CD44-HA相互作用参与HL60细胞的初始黏附,但不起主要作用。研究结果为抗肿瘤药物的开发提供参考。 展开更多
关键词 CD44 透明质酸 肿瘤细胞 细胞黏附 流体剪切力
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Construction of HA-1-DC Nucleic-acid Vaccine and Induction of Specific Cytotoxic T Lymphocytes
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作者 汪涯雅 张东华 +6 位作者 胡金梅 刘文励 周红升 张路 刘丹 黄振倩 谭获 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第3期261-264,共4页
An HA-1-DC nucleic-acid vaccine was constructed to induce anti-leukemia effect after hematopoietic stem cell transplantation (HSCT). DCs were generated from HSCT donors in vitro, and its immunologic activity was assay... An HA-1-DC nucleic-acid vaccine was constructed to induce anti-leukemia effect after hematopoietic stem cell transplantation (HSCT). DCs were generated from HSCT donors in vitro, and its immunologic activity was assayed by using flow cytometry and mixed lymphocytes reaction. HA-1 gene was electroporated into the cultured DCs to construct a DC nucleic-acid vaccine. After transfection for 48 h, the expression of HA-1 protein could be detected by using Western blot. The DCs were cultured with syngenic lymphocytes to induce specific cytotoxic T lymphocytes (CTLs). The cytoxicity of the CTLs was detected by LDH assay. The results showed that The DCs derived from peripheral blood monocytes (PBMCs) expressed the phenotype of DCs, and were effective in stimulating proliferation of the allogenic lymphocytes. After electroporating for 48-h, HA-1 protein was detected by using Western blot. The cytotoxity of inducing CTLs was higher than the control group. It was suggested that minor histocompatibility antigen HA-1 could be considered as a target of immunotherapy against leukemia after HSCT. 展开更多
关键词 dendritic cell ha-1 nucleic-acid vaccine hematopoietic stem cell transplantation cy- totoxic T lymphocyte
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Clinical Study on Facial Rejuvenation of Non-crosslinked Small Molecule Hyaluronic Acid Combined with Filorga NCTF®BOOST135 HA
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作者 He LIU Qin-bao HU Qiang YUAN 《Chinese Journal Of Plastic and Reconstructive Surgery》 2019年第3期46-50,共5页
Objective To observe the clinical application of non-crosslinked small molecule hyaluronic acid combined with Filorga NCTF®BOOST135HA in facial rejuvenation.Methods A total of 156 patients were selected from the ... Objective To observe the clinical application of non-crosslinked small molecule hyaluronic acid combined with Filorga NCTF®BOOST135HA in facial rejuvenation.Methods A total of 156 patients were selected from the outpatient department of our department from January 2017 to January 2018,including 36 males and 120 females.They were randomly divided into treatment group(82 cases)and control group(74 cases).The age of the treatment group was 25-50 years old,with an average age of 34 years old,while that of the control group was 26-48 years old,with an average age of 35 years old.group A was treated with non-crosslinked small molecule hyaluronic acid combined with Filorga NCTF®BOOST135 HA,while group B was treated with non-crosslinked small molecule hyaluronic acid alone.Through two methods,the facial skin state is analyzed and the therapeutic effect is evaluated.Results Follow-up for 3-6 months after treatment showed that 73 cases were satisfied and 9 cases were not satisfied in group A,with a satisfaction rate of 89.02%.In group B,52 cases were satisfied and 22 cases were dissatisfied,with a satisfaction rate of 70.27%.Conclusion Hyaluronic acid combined with Filorga NCTF®BOOST135 HA is better than hyaluronic acid alone in the treatment of facial rejuvenation,and patients obtain higher satisfaction. 展开更多
关键词 Non-crosslinked small molecule hyaluronic acid Filorga NCTF®BOOST135 ha Electronic syringe
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CHAP-Hyaluronic Acid (CHAP-HA) Filler as an Optimal Candidate for Forehead Filler Augmentation Using a 3-Point Injection Technique
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作者 Hsiao-Tung Lee Haw-Yueh Thong 《Journal of Cosmetics, Dermatological Sciences and Applications》 2021年第2期76-83,共8页
Minimally invasive forehead augmentation is becoming increasingly popular in Asia. However, treatment of the glabella is associated with injection-related complications. The safety of injections can be increased throu... Minimally invasive forehead augmentation is becoming increasingly popular in Asia. However, treatment of the glabella is associated with injection-related complications. The safety of injections can be increased through a thorough understanding of the anatomy and precise injection planes. The authors propose a 3-point injection technique for forehead augmentation in Asian patients that uses CHAP-hyaluronic acid (CHAP-HA) filler. The longevity of the filler was assessed using high-resolution ultrasound (HRU) imaging. Fifteen patients were examined using HRU before and immediately after treatment and at 1 month, 3 months, 6 months, and 12 months. As evident in HRU imaging, CHAP-HA remained visible within surrounding tissue for 6.4 ± 3.7 months. The mean Global Aesthetic Improvement Scale rating was 2.4 ± 0.5 immediately after treatment, 2.8 ± 0.3 at 1 month, 2.7 ± 0.5 at 3 months, 2.1 ± 0.6 at 6 months, and 1.5 ± 0.6 at 12 months. Minimal side effects were reported. The authors demonstrated that CHAP-HA filler may be an optimal candidate for forehead filler augmentation using a 3-point injection technique. 展开更多
关键词 ChaP-Hyaluronic acid (ChaP-ha) Filler High-Resolution Ultrasound (HRU) Forehead Augmentation
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35 kDa透明质酸片段B-HA对白细胞移走与活性氧水平的影响
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作者 郭田田 王家麒 +1 位作者 贾潇潇 惠觅宙 《青岛农业大学学报(自然科学版)》 2023年第2期104-111,共8页
旨在开发一种组织渗透性好的35 kDa生物活性透明质酸片段(bioactive hyaluronic acid fragment,B-HA),并围绕着B-HA对白细胞移走与活性氧水平的影响展开研究,探究其临床抗炎机制,为B-HA在临床领域的应用提供试验依据。使用重组人透明质... 旨在开发一种组织渗透性好的35 kDa生物活性透明质酸片段(bioactive hyaluronic acid fragment,B-HA),并围绕着B-HA对白细胞移走与活性氧水平的影响展开研究,探究其临床抗炎机制,为B-HA在临床领域的应用提供试验依据。使用重组人透明质酸酶PH20切割高分子量透明质酸,制备低分子量35 kDa的透明质酸片段B-HA;使用伽马相机动态采集小鼠体内放射性元素标记的99m Tc-B-HA的组织分布;使用最接近人体临床研究的新鲜提取的人外周血中性粒细胞和单个核细胞(淋巴细胞为主),采用琼脂糖微滴法探究B-HA对人中性粒细胞和单个核细胞移走的影响。99m Tc-B-HA组织分布显示,B-HA静脉注射后血液半衰期仅为5 min,除绝大部分进入代谢器官肝脏,其余大部分分布在淋巴器官脾脏;300μg/mL的B-HA促进了新鲜提取的人外周血单个核细胞移走(P<0.05),300μg/mL的B-HA在有(P<0.001)和没有(0.001<P<0.05)内毒素LPS存在的情况下均明显抑制外周血中性粒细胞的移走,40μg/mL的B-HA抑制了人外周血中性粒细胞产生活性氧水平(P<0.01)。 展开更多
关键词 透明质酸片段B-ha 组织分布 中性粒细胞 单个核细胞 移走 活性氧
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泥炭土腐殖酸环境室内模拟试验研究
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作者 曹净 俞扬首 朱伟明 《安全与环境学报》 CAS CSCD 北大核心 2024年第5期1804-1815,共12页
为能提供一种贴合天然环境的泥炭土腐殖酸环境,通过在冲洪积黏性土中掺入胡敏酸(Humic Acid, HA)试剂和富里酸(Fulvic Acid, FA)试剂人工制备泥炭土试样,并将试样浸泡在富里酸液中来模拟泥炭土腐殖酸环境。采用腐殖酸含量检测试验、扫... 为能提供一种贴合天然环境的泥炭土腐殖酸环境,通过在冲洪积黏性土中掺入胡敏酸(Humic Acid, HA)试剂和富里酸(Fulvic Acid, FA)试剂人工制备泥炭土试样,并将试样浸泡在富里酸液中来模拟泥炭土腐殖酸环境。采用腐殖酸含量检测试验、扫描电镜(Scanning Electron Microscope, SEM)、X射线衍射(X-Ray Diffraction, XRD)、X射线荧光光谱(X-Ray Fluorescence spectroscopy, XRF)和无侧限抗压强度(qu)试验来评估模拟效果及可行性。结果表明,在pH值为6.0的浸泡液中浸泡90 d后,试样中富里酸实测质量分数超过了初始掺量,而胡敏酸的实测质量分数相较于初始掺量表现出波动性。试样中孔隙随着腐殖酸掺量的增加而逐渐发育连通,试样所含的原生矿物主要为石英和云母,主要元素为O、Si、Al和Fe。通过与天然泥炭土环境对比分析,揭示了模拟的腐殖酸环境在微观特征上与天然腐殖酸环境具有相似性。宏观力学试验结果表明,模拟试样的qu随腐殖酸掺量的增加而降低,对比分析显示模拟试样的力学性能与天然泥炭土的力学性能接近。以上结果表明,采用所提出的方法可以模拟出与天然泥炭土环境相近的泥炭土腐殖酸环境。 展开更多
关键词 安全工程 泥炭土 腐殖酸 胡敏酸 富里酸 微观试验 无侧限抗压强度
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n-HA/多元氨基酸共聚物复合材料的制备和界面研究 被引量:6
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作者 刘永磊 李鸿 +3 位作者 吕国玉 南景天 罗小满 严永刚 《功能材料》 EI CAS CSCD 北大核心 2010年第4期566-569,共4页
通过原位聚合法制备了纳米磷灰石晶体(n-HA)/多元氨基酸共聚物(PA)复合材料,采用扫描电镜和燃烧试验测试了复合材料中n-HA的分散状况及材料的均一性,并用红外吸收光谱仪(FT-IR),X射线衍射仪(XRD)及X射线光电子能谱仪(XPS)对复合材料的... 通过原位聚合法制备了纳米磷灰石晶体(n-HA)/多元氨基酸共聚物(PA)复合材料,采用扫描电镜和燃烧试验测试了复合材料中n-HA的分散状况及材料的均一性,并用红外吸收光谱仪(FT-IR),X射线衍射仪(XRD)及X射线光电子能谱仪(XPS)对复合材料的表界面进行了测试和表征。结果表明,采用本方法制备的n-HA/PA复合材料中,n-HA微粒粒径约为80~100nm,能够很好地分散在PA基体中,材料具有良好的均一性;在复合材料n-HA与PA界面之间存在氢键和其它的化学结合,界面结合较稳定,具有良好的力学性能,是潜在的生物医学材料。 展开更多
关键词 纳米磷灰石 多元氨基酸共聚物 复合材料 界面作用
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H9N2亚型猪流感病毒山东分离株的分离鉴定及其HA、NP、NS基因序列分析 被引量:15
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作者 许传田 赵宏坤 范伟兴 《中国兽医学报》 CAS CSCD 北大核心 2004年第6期528-530,共3页
从山东地区疑似流感发病猪分离到 10株流感病毒 ,经国家流感中心鉴定均为 A型流感病毒 H9N2亚型。将其中 1株 Sw/ SD/ 1/ 2 0 0 3(H9N2 )的血凝素基因 (HA)、核蛋白基因 (NP)和非结构蛋白基因 (NS)进行克隆与测序 ,与Gen Bank收录的其... 从山东地区疑似流感发病猪分离到 10株流感病毒 ,经国家流感中心鉴定均为 A型流感病毒 H9N2亚型。将其中 1株 Sw/ SD/ 1/ 2 0 0 3(H9N2 )的血凝素基因 (HA)、核蛋白基因 (NP)和非结构蛋白基因 (NS)进行克隆与测序 ,与Gen Bank收录的其他猪流感和禽流感 H9N2亚型的相关基因进行比较 ,推测 Sw/ SD/ 1/ 2 0 0 3(H9N2 )可能源于禽流感病毒 H9N2亚型和 H5 N1亚型的重组病毒 ;Sw/ SD/ 1/ 2 0 0 3的 HA氨基酸裂解位点与其他 H9N2亚型不同 ,Sw/ SD/1/ 2 0 0 3的 HA氨基酸裂解位点是 R- S- L- R- G,而其他猪流感和禽流感 H9N2亚型都是 R- S- S- R- G。 展开更多
关键词 H9N2亚型 流感病毒 山东分离株 分离鉴定 ha NP NS基因 序列分析
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聚合氯化铁-腐殖酸(PFC-HA)絮体的粒度和分形维数的动态变化 被引量:8
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作者 卢佳 王毅力 +3 位作者 杜白雨 郑雅芹 石宝友 王东升 《环境科学学报》 CAS CSCD 北大核心 2008年第4期624-633,共10页
通过采集PFC-HA絮体的单个样品和拍摄它们的二维图像,研究了在不同混凝条件下絮体的粒度和分形维数的变化.结果表明,原水pH的下降滞后了PFC-HA絮体的出现.原水pH≥7.0时,随着投药量的增加,PFC-HA絮体的分形维数D2(lgA-lgdL)和D3(lgV1-lg... 通过采集PFC-HA絮体的单个样品和拍摄它们的二维图像,研究了在不同混凝条件下絮体的粒度和分形维数的变化.结果表明,原水pH的下降滞后了PFC-HA絮体的出现.原水pH≥7.0时,随着投药量的增加,PFC-HA絮体的分形维数D2(lgA-lgdL)和D3(lgV1-lgdL)随之降低,表明絮体的结构越来越疏松;而原水pH=5.0时,PFC-HA絮体的分形维数存在波动.在PFC的最佳投药量时,水力条件的优化可以提高HA的去除效果,但随着原水pH的下降,HA去除效果的提高程度也随之减小.在最佳水力条件下,PFC-HA絮体的粒度为数百微米,其分形维数值较大,表明絮体的结构较为密实.此外,PFC-HA絮体的粒度分布具有(类)分形特征,最佳水力条件下正的Dp值表明絮体的粒度分布趋向平稳.在整个混凝搅拌过程中,PFC-HA絮体的分形维数的变化是与混凝的溶液化学条件、搅拌时间和分形维数类型有关,其D2具有先上升后下降的趋势,这一过程中絮体结构先趋向密实,然后趋向疏松.而且慢速搅拌过程中絮体的尺度也是先增加后下降. 展开更多
关键词 聚合氯化铁-腐殖酸(PFC-ha)絮体 图像分析 粒度 分形维数 动态变化
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聚合氯化铁-腐殖酸(PFC-HA)絮体的不同拓扑空间下分形维数的研究 被引量:7
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作者 王毅力 卢佳 +3 位作者 杜白雨 魏科技 石宝友 葛小鹏 《环境科学学报》 CAS CSCD 北大核心 2008年第4期606-615,共10页
通过对PFC混凝去除水中HA过程中所形成的PFC-HA絮体的研究结果表明,原水pH分别为9.0、7.0和5.0时,最佳投药量下形成的絮体的平均沉降速度之间的比值为1.17∶1.00∶0.49,而且所有絮体的水平投影方向的平均直径与垂直投影方向的平均直径... 通过对PFC混凝去除水中HA过程中所形成的PFC-HA絮体的研究结果表明,原水pH分别为9.0、7.0和5.0时,最佳投药量下形成的絮体的平均沉降速度之间的比值为1.17∶1.00∶0.49,而且所有絮体的水平投影方向的平均直径与垂直投影方向的平均直径的比值均接近0.85.结合Logan公式和有效密度-长轴的双对数关系计算出的絮体三维空间的分形维数Df较为可靠,在本试验中3种pH的原水下形成的PFC-HA絮体的Df均小于2.0.絮体沉降速度的变化是质量分形维数Df、有效密度和粒径等因素的变化综合影响结果,因此,絮体的Df、有效密度各自的变化趋势有可能与沉降速度的不一致.原水pH=7.0时絮体的Df稍大于原水pH=9.0时絮体的Df,但比原水pH=5.0时絮体的Df大11.73%.可见,与原水pH=9.0时形成的絮体相比,原水pH=7.0时形成了稍微密实的小絮体,但原水pH=5.0时却形成了较为疏松的、很小的絮体.在本试验的图像分辨率下,PFC-HA絮体在一维拓扑空间下的分形维数D1比较低,一般都低于1.10.基于投影面积-长轴关系计算的二维拓扑空间的分形维数D2变化趋势为样品3稍大于样品2,样品1最小;然而基于投影面积-周长计算的二维拓扑空间的分形维数D2却呈现不同的变化趋势.另外,尽管PFC-HA絮体的Df小于2,但其与基于投影面积-长轴关系计算的二维拓扑空间的分形维数D2不相等,不符合Meakin的结论,这与本试验中CCD相机的分辨率和絮体样本数量有关. 展开更多
关键词 聚合氯化铁-腐殖酸(PFC-ha)絮体 拓扑空间 分形维数 沉降速度 有效密度 图像分析
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自身免疫性心肌炎大鼠模型血清HA和LN的表达 被引量:3
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作者 韩丽娜 李铁岭 +4 位作者 张亚晶 杨庭树 丁宇 郭树理 赵晓宁 《放射免疫学杂志》 CAS 2011年第1期1-4,共4页
目的:探讨实验性自身免疫性心肌炎(EAM)大鼠血清透明质酸(HA)和层黏连蛋白(LN)的动态变化及其意义。方法:Lewis大鼠60只,随机等分为6组,其中5组采用心肌C蛋白和完全弗氏佐剂足底注射,百日咳毒素腹腔内注射制作EAM大鼠模型。在免疫注射... 目的:探讨实验性自身免疫性心肌炎(EAM)大鼠血清透明质酸(HA)和层黏连蛋白(LN)的动态变化及其意义。方法:Lewis大鼠60只,随机等分为6组,其中5组采用心肌C蛋白和完全弗氏佐剂足底注射,百日咳毒素腹腔内注射制作EAM大鼠模型。在免疫注射后1w、2w、4w、6w和8w,取心脏,行苏木素-伊红染色检测心肌炎症积分,天狼星红染色检测心肌纤维化积分,同时行放射免疫分析检测血清HA和LN。另外1组不予免疫注射,作为空白组。结果:EAM大鼠心肌炎症积分在免疫注射后1w较空白组大鼠无明显改变,2w后迅速升高,高水平状态维持到第4w,以后逐渐下降;心肌间质纤维化积分在免疫注射后第1w、2w较空白组大鼠无明显改变,第4w后迅速升高,并维持高水平状态到第8w;血清HA和LN在免疫注射后第1w、2w水平较空白组大鼠无明显改变,第4w迅速升高,并维持高水平状态到第8w,同心肌间质纤维化积分变化一致。结论:血清HA和LN水平可作为判断心肌自身免疫性心肌炎心肌间质纤维化程度和活动性,且能作为预测心脏病转归方向的指标。 展开更多
关键词 心肌炎 纤维化 层黏连蛋白 透明质酸
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血清HA、PCⅢ、CⅣ及LN的水平在肝纤维化与早期肝硬化中的意义 被引量:12
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作者 张怀宏 翟玉峰 +1 位作者 段钟平 高岩 《胃肠病学和肝病学杂志》 CAS 1999年第3期194-196,共3页
目的 通过检测血清透明质酸(HA) 、Ⅲ型前胶原(PCⅢ) 、Ⅳ型胶原(CⅣ) 及层粘素(LN) 的水平,了解该四项血清指标与肝纤维化及早期肝硬化的关系。方法 36 例慢性乙型肝炎( 慢乙肝) 患者的血清HA、PCⅢ及LN ... 目的 通过检测血清透明质酸(HA) 、Ⅲ型前胶原(PCⅢ) 、Ⅳ型胶原(CⅣ) 及层粘素(LN) 的水平,了解该四项血清指标与肝纤维化及早期肝硬化的关系。方法 36 例慢性乙型肝炎( 慢乙肝) 患者的血清HA、PCⅢ及LN 用放免法检测( RIA) ;CⅣ用酶免法检测(EIA) ,并与肝穿病理炎症分级(G) 和纤维化分期(S) 进行比较。结果 血清中HA、PCⅢ、CⅣ及LN 水平与肝纤维化及早期肝硬化关系密切( P< 0-05 - 0-01) 。结论 血清中HA、PCⅢ、CⅣ及LN 均为较好反映肝纤维化及早期肝硬化的指标。其中HA 价值最大。 展开更多
关键词 透明质酸 胶原 层粘素 肝纤维化 早期 肝硬化
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PDLLA/HA/FK506复合神经导管的制备及体外降解性能 被引量:4
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作者 陈蕾 闫玉华 +1 位作者 万涛 李世普 《武汉理工大学学报》 EI CAS CSCD 北大核心 2006年第11期41-43,106,共4页
以聚乳酸(PDLLA)为基材、纳米羟基磷灰石(HA)为添加剂、加入免疫抑制剂FK506,用溶剂挥发法制备PDLLA/HA/FK506复合神经导管。通过观察复合导管在磷酸缓冲溶液中降解时pH值变化、质量损耗及材料微观形貌,研究了该复合导管的体外降解性能... 以聚乳酸(PDLLA)为基材、纳米羟基磷灰石(HA)为添加剂、加入免疫抑制剂FK506,用溶剂挥发法制备PDLLA/HA/FK506复合神经导管。通过观察复合导管在磷酸缓冲溶液中降解时pH值变化、质量损耗及材料微观形貌,研究了该复合导管的体外降解性能。结果表明:加入适量纳米羟基磷灰石可以改善聚乳酸降解的酸性问题并提高其力学强度。免疫抑制剂FK506的加入对导管材料的降解性能有一定的影响。PDLLA/HA/FK506复合神经导管具有良好的降解性能。 展开更多
关键词 混旋聚乳酸(PDLLA) 羟基磷灰石(ha) 免疫抑制剂FK506 神经导管 降解性能
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PLGA/HA支架材料生物相容性的动物实验研究 被引量:4
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作者 张士杰 裴庆国 +2 位作者 潘可风 蒋欣泉 张秀丽 《口腔颌面外科杂志》 CAS 2007年第1期40-45,共6页
目的:通过动物实验评价新型多孔聚乳酸乙醇酸/羟基磷灰石(polyaiticglycolic acid/hydroxyapatite,PLGA/HA)支架材料的生物相容性。方法:分别将5%和10%HA掺量的PLGA/HA支架材料注射到昆明小鼠腹腔内、植入到新西兰大白兔体内,选择全身... 目的:通过动物实验评价新型多孔聚乳酸乙醇酸/羟基磷灰石(polyaiticglycolic acid/hydroxyapatite,PLGA/HA)支架材料的生物相容性。方法:分别将5%和10%HA掺量的PLGA/HA支架材料注射到昆明小鼠腹腔内、植入到新西兰大白兔体内,选择全身毒性试验、亚急性毒性试验、血液相容性试验、肌肉刺激试验等,对其生物相容性进行评价。结果:全身急慢性毒性试验显示材料种植到小鼠及兔子体内后,动物一般情况良好,2周后体重、红细胞计数、白细胞计数等生理参数未见明显变化;实验显示两种材料对兔混合血浆凝血功能无影响;溶血试验结果显示5%和10%的PLGA/HA的溶血率分别为2.67%和3.62%,均小于5%,完全符合医用材料对溶血试验的要求;肌肉刺激试验结果显示两种材料埋植后局部未见红肿,4周时部分PLGA/HA材料开始降解,降解部分有大量的纤维结缔组织生长;HE染色结果显示PLGA/HA基本不存在抗原性,植入机体4周后,材料周围未见明显炎症细胞浸润。结论:5%和10%HA掺量的PLGA/HA均具有良好的生物相容性和体内安全性。 展开更多
关键词 聚乳酸乙醇酸 羟基磷灰石支架 生物相容性 动物实验
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