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渗吸驱油的机理研究 预览
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作者 李传亮 毛万义 +1 位作者 吴庭新 朱苏阳 《新疆石油地质》 CAS CSCD 北大核心 2019年第6期687-694,共8页
渗吸驱油是裂缝性油藏的有效驱油方式,但渗吸驱油的机理一直没有得到统一的认识,应用相关知识对其进行深入研究,取得以下认识。渗吸有同向渗吸和逆向渗吸之分,地下的渗吸都是同向渗吸。渗吸有平面渗吸和垂向渗吸之分,垂向渗吸比平面渗... 渗吸驱油是裂缝性油藏的有效驱油方式,但渗吸驱油的机理一直没有得到统一的认识,应用相关知识对其进行深入研究,取得以下认识。渗吸有同向渗吸和逆向渗吸之分,地下的渗吸都是同向渗吸。渗吸有平面渗吸和垂向渗吸之分,垂向渗吸比平面渗吸复杂,地下的渗吸都是垂向渗吸。渗吸可分为单边接触式渗吸、双边接触式渗吸和周围接触式渗吸,地下的渗吸为周围接触式渗吸。渗吸有毛细管压力渗吸和浮力渗吸之分,毛细管压力渗吸只能吸水排油,浮力渗吸既可以吸水排油,也可以吸油排水,地下的渗吸都是浮力渗吸。大孔隙中的渗吸速度快,小孔隙中的渗吸速度慢。末端效应会滞留一部分油,降低渗吸效率。在水中加入表面活性剂,可降低末端效应。岩块越大,渗吸采收率就越高,但渗吸时间就越长,可通过实验优化岩块大小及体积压裂的岩石破碎程度。 展开更多
关键词 裂缝性油藏 岩石 基质岩块 孔隙 毛细管 毛细管压力 浮力 渗吸 岩心 驱油
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毛细管精馏分离乙酸乙酯-乙醇共沸物 预览
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作者 胡运通 艾波 +2 位作者 许保云 翟金国 黄前程 《化学工程》 CAS CSCD 北大核心 2019年第8期35-38,44共5页
基于高效分离共沸物的目的,实验采用内部具有毛细管结构的活性氧化铝颗粒作为精馏填料,对乙酸乙酯-乙醇进行分离,为开发一种填料毛细管精馏技术高效分离共沸物提供研究基础。文中主要考察了原料组成、回流比和填料高度等单因素对塔顶乙... 基于高效分离共沸物的目的,实验采用内部具有毛细管结构的活性氧化铝颗粒作为精馏填料,对乙酸乙酯-乙醇进行分离,为开发一种填料毛细管精馏技术高效分离共沸物提供研究基础。文中主要考察了原料组成、回流比和填料高度等单因素对塔顶乙酸乙酯纯度的影响,并通过均匀设计实验确定了最佳组合因素条件,然后又考察了活性氧化铝填料的回收使用情况,得出单因素最佳条件分别为:质量分数wF1=70%,R=5,H=1.5m;最佳组合因素条件为:质量分数wF1=81%,R=5.86,H=1.39m;填料回收:活性氧化铝填料重复使用仍可达到原始最佳水平,具有良好的回收再利用价值。 展开更多
关键词 毛细管精馏 共沸物 乙酸乙酯 乙醇
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毛管入口流量估算方法与验证 预览
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作者 段晓辉 牛文全 《干旱地区农业研究》 CSCD 北大核心 2019年第3期91-95,103共6页
为便捷估算特定压力下的毛管入口流量值,选择了毛管长度、毛管铺设坡度、毛管管径、滴头间距、流量系数和流态指数等6个影响因素,采用计算机模拟计算和实测验证相结合的方法,确定了毛管入口流量估算模型和参数估算方法。结果表明,毛管... 为便捷估算特定压力下的毛管入口流量值,选择了毛管长度、毛管铺设坡度、毛管管径、滴头间距、流量系数和流态指数等6个影响因素,采用计算机模拟计算和实测验证相结合的方法,确定了毛管入口流量估算模型和参数估算方法。结果表明,毛管长度、毛管铺设坡度、滴头间距和流量系数显著影响毛管入口流量系数 a,毛管铺设坡度和流态指数显著影响毛管入口流量系数 b;确定了系数 a和b 的计算式,与退步法计算结果比较,平均相对误差分别为2.30%和0.70%;当毛管入口工作水头分别为4、6 m和8 m时,毛管入口流量估算模型计算结果与实测值的平均相对误差为3.79%,精度较高,在微灌系统设计中,可以采用本文建立的模型估算毛管入口流量。 展开更多
关键词 滴灌 水力学解析 毛管 压力 入口流量
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视盘型视网膜毛细血管瘤的临床分析
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作者 李静 肖静 梁建宏 《中华眼科杂志》 CAS CSCD 北大核心 2019年第8期609-615,共7页
目的探讨视盘型视网膜毛细血管瘤(JRCH)的临床特点及治疗。方法回顾性病例研究。收集2004至2017年在北京大学人民医院眼科确诊的视盘型视网膜血管瘤的患者6例(7只眼)的临床资料。其中男性患者4例(5只眼),女性患者2例(2只眼),初诊年龄14... 目的探讨视盘型视网膜毛细血管瘤(JRCH)的临床特点及治疗。方法回顾性病例研究。收集2004至2017年在北京大学人民医院眼科确诊的视盘型视网膜血管瘤的患者6例(7只眼)的临床资料。其中男性患者4例(5只眼),女性患者2例(2只眼),初诊年龄14~67岁。其中,2只眼行激光治疗[经瞳孔温热疗法(TTT)或光动力疗法(PDT)],2只眼单纯行眼内注射抗新生血管因子(VEGF)药物治疗。2只眼初诊为玻璃体积血的患者行玻璃体切除术+抗VEGF治疗。1只眼未给予治疗。结果6例患者(7只眼)就诊时4只眼合并黄斑水肿;2只眼合并玻璃体积血;1只眼合并黄斑前膜;3例患者合并VHL综合征。长期随访发现,行TTT治疗的2只眼视力均有下降;单纯行抗VEGF治疗的2只眼中合并黄斑水肿的1只眼视力有所提高,合并黄斑前膜的1只眼视力无明显变化;行玻璃体切除术+抗VEGF联合治疗的2只眼视力均有提高。1只眼未治疗视力稳定。结论JRCH是发生在视盘上或近视盘旁的橙黄色或红色的血管性错构瘤,常合并黄斑水肿、玻璃体积血和局部视网膜下渗出。对症处理并发症可有效提高视力,无并发症者可长期随访观察,激光治疗效果不佳。 展开更多
关键词 视网膜肿瘤 血管瘤 毛细管 视盘 随访研究
不锈钢感温组件激光焊裂纹形成原因及改进措施 预览
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作者 王艳 张丽 +3 位作者 李莹 孟宪阔 赵鹏飞 吴世品 《制冷与空调》 2019年第7期37-40,共4页
针对制冷系统中不锈钢感温组件激光焊接头出现的裂纹缺陷,分析激光焊裂纹的形成位置、断口形貌和微观组织,结果表明:激光焊裂纹主要为凝固裂纹,形成于焊缝中心;凝固裂纹的形成主要与感温组件原材料采用的不锈钢中Cr当量与Ni当量的比值(C... 针对制冷系统中不锈钢感温组件激光焊接头出现的裂纹缺陷,分析激光焊裂纹的形成位置、断口形貌和微观组织,结果表明:激光焊裂纹主要为凝固裂纹,形成于焊缝中心;凝固裂纹的形成主要与感温组件原材料采用的不锈钢中Cr当量与Ni当量的比值(Creq/Nieq)、S和P元素(杂质)含量、焊前清理和装配间隙有关;当不锈钢的Creq/Nieq较低时,凝固裂纹敏感性高,易产生凝固裂纹,控制不锈钢的Creq/Nieq>1.65可以有效降低凝固裂纹的敏感性;严格控制不锈钢的S和P含量,加强焊前清理,减小装配间隙,可有效降低激光焊过程中的裂纹缺陷,提高产品的焊接质量。 展开更多
关键词 感温组件 不锈钢 毛细管 激光焊 焊缝 凝固裂纹
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Reactive capillary hemangiomas: a novel dermatologic toxicity following anti-PD-1 treatment with SHR-1210 预览
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作者 Xuelian Chen Lanying Ma +7 位作者 Xi Wang Hongnan Mo Dawei Wu Bo Lan Dong Qu Hongtu Zhang Jing Huang Binghe Xu 《癌症生物学与医学:英文版》 CAS CSCD 2019年第1期173-180,共8页
Objective: SHR-1210 is a new and promising anti-PD-1 agent for solid tumors. During the phase I study of SHR-1210, we encountered a novel but prevalent immune-related dermatologic toxicity: reactive capillary hemangio... Objective: SHR-1210 is a new and promising anti-PD-1 agent for solid tumors. During the phase I study of SHR-1210, we encountered a novel but prevalent immune-related dermatologic toxicity: reactive capillary hemangiomas(RCHs). Thus we tried to summarize the features of RCHs and estimate their relationship with tumor response.Methods: This prospective observational study systematically enrolled 98 patients with advanced solid tumors from April 27th,2016 to June 8th, 2017 in the context of the phase I clinical study of SHR-1210. This report focused on the skin toxicities. Patients underwent entire skin inspection every two weeks while taking medication. The clinical course of RCHs was recorded and their association with tumor response was estimated. The data cut-off date was November 15th, 2017.Results: After a median follow-up of 242(range, 29–567) days, RCHs were observed in 85.7%(84/98) of patients on cutaneous/mucosal surfaces;84.5%(71/84) of the RCHs were evaluated as grade 1 adverse events. No grade 3 or 4 RCHs were observed. The time of onset of RCHs was dose dependent and shortest in the 400 mg-dose cohort(P < 0.001). Spontaneous and complete regression of RCHs was observed both during and after treatment. The objective response rate of tumors for patients with RCHs was 28.9%(24/83). However, no responders were observed among the patients without RCHs.Conclusions: RCHs were prevalent but manageable during treatment with SHR-1210. It might add to the expanding literature regarding immune-related dermatologic adverse events. 展开更多
关键词 REACTIVE capillary HEMANGIOMAS SHR-1210 skin TOXICITY ANTI-TUMOR efficacy
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棉花膜下“一管四行”滴灌工程设计探讨 预览 被引量:1
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作者 张晔 《水资源开发与管理》 2019年第2期16-19,共4页
本文以新疆昌吉市头屯河灌区农田项目为例,针对棉花田间灌溉区水资源利用率较低、灌水定额偏高、水资源严重浪费等问题,提出棉花膜下“一管四行”滴灌工程的管网布置方案,并详细介绍了相关参数的计算方法。该工程采用的滴灌模式为“支管... 本文以新疆昌吉市头屯河灌区农田项目为例,针对棉花田间灌溉区水资源利用率较低、灌水定额偏高、水资源严重浪费等问题,提出棉花膜下“一管四行”滴灌工程的管网布置方案,并详细介绍了相关参数的计算方法。该工程采用的滴灌模式为“支管+辅管”,大大降低了棉花田间灌溉区的灌溉用水量,将灌溉水利用率提高到了97%,缓解了区域内水资源的供需矛盾,其经验可为类似工程提供必要的技术参考。 展开更多
关键词 节水灌溉 滴灌工程 “一管四行” 毛管 设计
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冷冻靶黑腔氦气充注过程数值模拟与分析 预览
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作者 郭富城 李翠 +1 位作者 陈洵 厉彦忠 《西安交通大学学报》 EI CAS CSCD 北大核心 2019年第11期79-84,90,共7页
基于Hagen-Poiseuille公式、耦合气体增压微分方程及气体状态方程,采用Matlab编程的形式建立了黑腔内部气体增压物理模型,针对冷冻靶黑腔氦气增压问题进行了数值模拟与分析。结果表明:在氦气充注过程中采用连续流体模型计算即可满足精... 基于Hagen-Poiseuille公式、耦合气体增压微分方程及气体状态方程,采用Matlab编程的形式建立了黑腔内部气体增压物理模型,针对冷冻靶黑腔氦气增压问题进行了数值模拟与分析。结果表明:在氦气充注过程中采用连续流体模型计算即可满足精度要求;毛细管的通流能力对腔内压力及温升影响剧烈,在氦气初始温度相同的情况下,毛细管通流能力越大,氦气充注速率越大,但同时腔内气体温升较高;设置冷壁制冷变功率策略后,随着冷壁最大制冷功率增加,充气速率降低,腔内温升降低,冷壁最大制冷功率提高0.5 mW,腔内最大温升下降约13 K;氦气的初始温度对充注过程有较大影响,氦气初始温度降低1 K,充气时间减少约0.6 s,腔内气体最大温升降低约0.1 K。所提出的方法可推广至靶内燃料气体充注及腔内抽空流洗情形,从而可为解决腔内气体充注问题提供一种有效便捷的数值模拟方法。 展开更多
关键词 氦气增压 毛细管 Hagen-Poiseuille公式 数值模拟
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Open tubular capillary electrochromatography with block co-polymer coating for separation of β-lactam antibiotics
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作者 Liping Zhao Juan Qiao +2 位作者 Hongyi Zhang Fangnan Xie Li Qi 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期349-352,共4页
A new open-tubular capillary electrochromatography (OT-CEC) method for analysis of β-lactam antibiotics has been developed with unique block co-polymer coating. To obtain the highly ordered block polymer chains, reve... A new open-tubular capillary electrochromatography (OT-CEC) method for analysis of β-lactam antibiotics has been developed with unique block co-polymer coating. To obtain the highly ordered block polymer chains, reversible addition fragmentation chain transfer radical polymerization method was used to synthesize poly (maleic anhydride-styrene-N-isopropylacrylamide). The prepared block copolymer coating was characterized with NMR, fourier transform infrared spectroscopy and scanning electron microscope. Several key separation factors of OT-CEC, which including polymer amount,stability of the coating, temperature, species of organic additives, buffer pH and concentration, were investigated in detail. Our results indicated that the separation efficiency was improved greatly with the coating capillary and the three test analytes could be baseline separated. Then, the separation mechanism was briefly explored. Moreover, the proposed OT-CEC method displayed promising quantitative analysis property of the three test analytes with good linearity (R2>0.99), repeatability (relative standard deviations <0.9%) and high recovery (95.4%-106.2%). Further, the assay was applied in monitoring the three test β-lactam antibiotics (cephradine, cephalexin and amoxicillin) in serum samples, providing a useful platform for construction of novel polymer coatings in OT-CEC system and for analysis of drugs in real bio-samples. 展开更多
关键词 OPEN-TUBULAR capillary Electrochromatography Β-LACTAM antibiotics BLOCK CO-POLYMER COATING Serum drugs SEPARATION
Predicting the entire soil-water characteristic curve using measurements within low suction range
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作者 YE Yun-xue ZOU Wei-lie +1 位作者 HAN Zhong LIU Xiao-wen 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1198-1214,共17页
The soil-water characteristic curve(SWCC) is widely used in the design and evaluation in the practice of geotechnical and geoenvironmental engineering such as the slope stability under the influence of environmental f... The soil-water characteristic curve(SWCC) is widely used in the design and evaluation in the practice of geotechnical and geoenvironmental engineering such as the slope stability under the influence of environmental factors. The SWCC has distinct features in the capillary and adsorption zones due to different physical mechanisms. Measurements of the SWCC are typically limited within the capillary zone(i.e., low suction range). It is cumbersome and time-consuming to measure the SWCC in the adsorption zone(i.e., high suction range). This study presents a simple method to predict the entire SWCC within both the capillary and adsorption zones, using measured data only from low suction range(e.g., from 0 to 500 kPa). Experimental studies were performed on a completely weathered granite residual soil to determine its entire SWCC from saturated to dry conditions. The resultant SWCC, along with the SWCC measurements of 14 soils reported in the literature, were used to validate the proposed method. The results indicate that the proposed method has good consistency with a wide array of measured data used in this study. The proposed method is easy to use as it only requires a simple parameter calibration for a commonly used SWCC model. It can be used to improve the reliability in the prediction of the SWCC over the entire suction range when measurements are limited within the low suction range. 展开更多
关键词 UNSATURATED SOILS SOIL-WATER characteristic CURVE CAPILLARY Adsorption Prediction
乙醇中微量异丙醇气相色谱法测定研究 预览
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作者 毛芝旺 《广东化工》 CAS 2019年第13期200-201,193共3页
提出了工业乙醇中微量异丙醇气相色谱法测定的分析方法。采用极性多孔高聚物(聚苯乙烯-二乙烯基苯)键合毛细管柱分离乙醇中的异丙醇,以内标法进行定量。方法的相对标准偏差RSD为0.21%,加标平均回收率达99.7%。
关键词 乙醇 异丙醇 毛细管 气相色谱
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Activation of SIRT1 ameliorates LPS-induced lung injury in mice via decreasing endothelial tight junction permeability
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作者 Cui-ping Fu Sheng-yu Hao +6 位作者 Xiao-bo Xu Jian Zhou Zi-long Liu Huan Lu Li-min Wang Wei-zhong Jin Shan-qun Li 《中国药理学报:英文版》 SCIE CAS CSCD 2019年第5期630-641,共12页
The integrity of the endothelial barrier is a determinant of the prognosis of lipopolysaccharide (LPS)-induced acute lung injury (ALI). In this study, we investigated whether and how Sirtuin 1 (SIRT1) maintained the v... The integrity of the endothelial barrier is a determinant of the prognosis of lipopolysaccharide (LPS)-induced acute lung injury (ALI). In this study, we investigated whether and how Sirtuin 1 (SIRT1) maintained the vascular integrity during ALI. An experimental model of ALI was established in mice through intratracheal administration of LPS (10 mg/kg). LPS stimulation significantly increased the pulmonary permeability and decreased the expression of SIRT1 and tight junction proteins (TJs), including occludin, claudin-5, tight junction protein 1 and tight junction protein 2. Morphological studies showed that LPS induced obvious lung injury with inammatory cell infiltration in the interstitial and alveolar space, hemorrhage, edema, and the thickened alveolar wall compared to the control mice. Intratracheal administration of the selective SIRT1 activator SRT1720 (6.25 mg/kg) significantly attenuated LPS- induced lung injury, lung hyper-permeability and increased TJs expression, whereas intratracheal administration of the selective SIRT1 inhibitor EX527 (6.25 mg/kg) aggravated LPS-induced ALI. Similar protective effects of SIRT1 on pulmonary cellular permeability were observed in primary human pulmonary microvascular endothelial cells treated with LPS (2 mg/mL) in vitro. We further demonstrated that the RhoA/ROCK signaling pathway was activated in SIRT1 regulation of tight junction permeability. The RhoA/ROCK inhibitor Y-27632 (10 μM) increased the expression of TJs and reversed LPS- or EX527-induced hyper-permeability. In conclusion, SIRT1 ameliorates LPS-induced lung injury via decreasing endothelial tight junction permeability, possibly via RhoA/ ROCK signaling pathway. This finding may contribute to the development of new therapeutic approaches for lung injury. 展开更多
关键词 lung injury LPS SIRT1 protein RhoA/ROCK capillary ENDOTHELIAL PERMEABILITY tight junction proteins SRT1720 EX527 Y-27632 human pulmonary MICROVASCULAR ENDOTHELIAL cells
高通量数字化毛细管微阵列芯片 预览
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作者 邱亚军 李金泽 +2 位作者 李传宇 张芷齐 周连群 《光学精密工程》 EI CAS CSCD 北大核心 2019年第6期1237-1244,共8页
针对数字PCR体系样品的分割方式,开发了一款数字PCR体系样品分割芯片,用于微量生物样品检测。利用微机电系统(MEMS)制备阵列化的硅基片,采用硅片高效低损伤超精密磨削减薄工艺对硅基片进行减薄,结合化学改性方法,成功制备了表面疏水孔... 针对数字PCR体系样品的分割方式,开发了一款数字PCR体系样品分割芯片,用于微量生物样品检测。利用微机电系统(MEMS)制备阵列化的硅基片,采用硅片高效低损伤超精密磨削减薄工艺对硅基片进行减薄,结合化学改性方法,成功制备了表面疏水孔壁亲水的毛细管微阵列芯片。通过扫描电子显微镜(SEM)对芯片结构进行表征,SEM结果显示,芯片结构为通孔微阵列。通过接触角表征芯片表面的疏水性,对比化学处理前后芯片表面的接触角,结果表明化学处理后芯片表面疏水,接触角为118°。通过能谱(EDS)表征芯片孔壁的亲水性,结果表明,芯片孔壁只有Si,O两种元素,形成亲水基团,因此,芯片孔壁亲水。通过测量显微镜和荧光显微镜表征芯片的样品分割性能,结果表明芯片将样品分割为均一的独立单元。通过激光共聚焦扫描仪表征,直观地反应了芯片的整体样品分割效果,通过计算芯片的样品填孔率为93.8%。本文成功制备了表面疏水孔壁亲水的毛细管微阵列芯片,该芯片具有优异的样品分割性能,在生物医学领域具有广阔的应用前景。 展开更多
关键词 微阵列芯片 高通量 数字化 毛细管 化学改性 亲疏水
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毛细管网供冷室内环境对比实验研究 预览
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作者 梁秋锦 陈金华 +3 位作者 段坤林 孙海 韩浩然 宋静 《土木与环境工程学报(中英文)》 CSCD 北大核心 2019年第4期185-192,共8页
在18℃供水温度下,对重庆地区毛细管网辐射供冷系统进行实验测试,分析了毛细管网顶棚、墙面、地面3种敷设方式的室内热工参数。结果表明:毛细管网顶棚、墙面、地面3种敷设方式供冷稳定时,人员活动区的平均温度依次为26.27、27.22、26.57... 在18℃供水温度下,对重庆地区毛细管网辐射供冷系统进行实验测试,分析了毛细管网顶棚、墙面、地面3种敷设方式的室内热工参数。结果表明:毛细管网顶棚、墙面、地面3种敷设方式供冷稳定时,人员活动区的平均温度依次为26.27、27.22、26.57℃,辐射表面平均温度依次为20.96、21.14、22.76℃,PMV依次为-0.27、0.32、-0.2,PPD依次为7.06%、7.47%、6.34%。在实验条件下,3种敷设方式供冷时室内温度均能满足≤28℃的要求,PMV、PPD均能满足《民用建筑室内热湿环境评价标准》(GB/T50785—2012)Ⅰ级热舒适评价指标。 展开更多
关键词 毛细管网 辐射供冷 敷设位置 室内环境
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人全血的毛细管显微拉曼光谱分析 预览
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作者 张铭 彭文 +4 位作者 赖珍荃 王泓鹏 袁汝俊 何强 万雄 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第3期797-801,共5页
血液中含有众多生物信息,如激素、酶、抗体等丰富的蛋白质成分。通过对血液中众多生物信息进行检测鉴定可以起到对该血液种属判定、溯源的目的。因此,血液检测技术的发展在诸如刑事案件侦破、物种鉴定、疾症预防等领域具有重要意义。目... 血液中含有众多生物信息,如激素、酶、抗体等丰富的蛋白质成分。通过对血液中众多生物信息进行检测鉴定可以起到对该血液种属判定、溯源的目的。因此,血液检测技术的发展在诸如刑事案件侦破、物种鉴定、疾症预防等领域具有重要意义。目前,传统血液检测手段多为显微观测、免疫法、DNA/基因检测法等,这些技术会对血液样本造成不可逆转的破坏性,且存在分析周期长、结构装置复杂、试验价格昂贵等问题。随着激光技术的发展,拉曼光谱技术作为一种非线性散射光谱技术,在血液检测技术中得到了应用。在血液检测技术中,拉曼光谱技术通常与共聚焦显微系统结合,对涂在载玻片上或盛放在透明容器中的血液样品进行光谱信号采集。该技术具有快速、无损等优势,但复杂的光路系统及昂贵的实验装置限制了该技术的广泛推广。为提出一种装置简单、操作简便的血液拉曼检测新技术,研究采用基于毛细管的显微拉曼技术方案采集并分析人全血的拉曼信号。血液样品通过毛细管的虹吸效应取样,与载玻片的涂样方式相比毛细管的方案具有模拟人血管、维持血液活性、减小空气对实验过程中血液成分的影响、降低激光对血液样品的灼伤效果等优势。为避开可见光部分荧光较强区域的荧光干扰,研究采用360nm紫外激光器作为激发光源,防止可见荧光信号的干扰。积分时间设为800ms,有效避免因激光长时间照射对血液样品的灼伤效果,影响实验数据的稳定性与真实性,光谱平均次数为2次,避免单次测量所带来的数据的不准确性影响。光谱扫描范围为500~1800cm^-1,结果表明此范围内可较好的避开可见光部分荧光较强区域的干扰。测得的拉曼光谱信号通过滤波去噪及基线校正进行处理。首先采用5阶离散小波变换滤波,进行1层信号分解,滤除高频噪声信号,保留� 展开更多
关键词 全血 毛细管 显微 拉曼光谱
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On-line trapping/capillary hydrophilic-interaction liquid chromatography/mass spectrometry for sensitive determination of RNA modifications from human blood
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作者 Chubo Qi Hanpeng Jiang +2 位作者 Jun Xiong Bifeng Yuan Yuqi Feng 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第3期553-557,共5页
RNA modification has recently been proposed to play important roles in biological regulation.The detection and quantification of RNA modifications generally are challenging tasks since most of the modifications exist ... RNA modification has recently been proposed to play important roles in biological regulation.The detection and quantification of RNA modifications generally are challenging tasks since most of the modifications exist in low abundance in vivo.Here we developed an on-line trapping/capillary hydrophilic-interaction liquid chromatography/electrospray ionization-mass spectrometry(on-line trapping/cHILIC/MS) method for sensitive and simultaneous quantification of RNA modifications of N~6-methyladenosine(m~6A) and 5-methylcytosine(5-mC) from human blood.The hydrophilic organic-silica hybrid monolith was prepared using sol-gel combined with "thiol-ene" click reaction for the separation of nucleosides.A poly(MAA-co-EGDMA) monolithic capillary was used as the on-line trapping column.With the developed on-line trapping/cHILIC/MS analytical platform, the detection limits of m~6A and 5-mC can reach to 0.06 fmol and 0.10 fmol.We then investigated the contents of m~6A and 5-mC in human blood RNA from healthy persons at the age of 6-14 and 60-68 years.Our results showed that both m~6A and 5-mC contents were significantly decreased in elder persons, suggesting the RNA modifications of m~6A and 5-mC are correlated to aging. 展开更多
关键词 N^6-Methyladenosine 5-Methylcytosine Hydrophilic-interaction liquid chromatography CAPILLARY monolithic column Mass spectrometry
穿刺灌洗联合臭氧局部注入治疗哺乳期乳腺脓肿的初步机制研究及临床疗效观察
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作者 张云锁 范丽莉 +5 位作者 杨卉 彭金娟 池华茂 俞斌武 王水 肇毅 《中国妇幼保健》 CAS 2019年第20期4617-4622,共6页
目的初步探讨穿刺灌洗联合臭氧局部注入治疗哺乳期乳腺脓肿的机制,同时进一步观察其临床治疗效果。方法选择2015年6月-2017年6月镇江市妇幼保健院诊治的60例哺乳期乳腺脓肿患者随机分为超声引导下穿刺灌洗联合臭氧局部注入治疗组(甲组)... 目的初步探讨穿刺灌洗联合臭氧局部注入治疗哺乳期乳腺脓肿的机制,同时进一步观察其临床治疗效果。方法选择2015年6月-2017年6月镇江市妇幼保健院诊治的60例哺乳期乳腺脓肿患者随机分为超声引导下穿刺灌洗联合臭氧局部注入治疗组(甲组)、超声引导下穿刺灌洗联合抗生素治疗组(乙组)及传统切开引流组(对照组)各20例。3组分别在首次治疗时、治疗后第3天、第6天切获取脓壁组织进行细菌培养计数,检测每克组织含菌量;在首次治疗时、治疗后第3天获取脓壁组织进行免疫组织化学检测,计算毛细血管含量;同时对比3种治疗方法的临床效果、外形美观及治疗费用等方面的差异。结果治疗开始时3组患者的脓壁组织含菌量和毛细血管含量差异无统计学意义(P>0. 05)。治疗3 d后,甲组和乙组的脓壁组织含菌量低于对照组,毛细血管含量高于对照组,甲组的组织含菌量低于乙组,而毛细血管含量高于乙组;治疗6 d后,甲组和乙组已无细菌生长,而对照组仍可见细菌生长。在治愈时间、局部处理次数、治疗过程中疼痛程度、治愈后瘢痕情况、继续哺乳率及治疗费用等方面,甲组和乙组明显优于对照组,而甲组优于乙组。结论超声引导下穿刺灌洗联合臭氧局部注入治疗患者哺乳期乳腺脓肿有利于脓腔内及脓壁组织细菌的清除,加快感染的控制,有利于局部组织毛细血管密度的增加,加快组织的愈合。可以替代抗生素的使用,显著缩短治愈时间,减少局部处理次数,无切口存在,明显改善了美观程度。 展开更多
关键词 穿刺灌洗 乳腺脓肿 臭氧 细菌 毛细血管
Review: Recent Advancement of Experimental and NumericalInvestigations for Breaking Waves 预览
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作者 Cheng Liu Yiding Hu +1 位作者 Zheng Li Decheng Wan 《哈尔滨工业大学学报:英文版》 EI CAS 2019年第5期1-16,共16页
Breaking wave is a complex physical phenomenon that takes place at the gas fluid interface which is the chief reason for the generation of two phase turbulence wave energy dissipation and mass transfer between air and... Breaking wave is a complex physical phenomenon that takes place at the gas fluid interface which is the chief reason for the generation of two phase turbulence wave energy dissipation and mass transfer between air and water. For marine hydrodynamics the breaking bow wave of high speed vessels induces the bubble mixed flow travelling around the ship eventually developing to be the turbulent wake which is easy to be detected by photoelectric equipment. Besides the flow induced noise stemming from wave plunging may weaken the acoustic stealth of water surface craft. In the oceanographic physics context wave breaking accounts for the energy and mass exchange of the ocean atmosphere system which has a great effect on the weather forecasts and global climate predictions. Due to multi scale properties of multiphase turbulent flows a wide range of time and length scales should be resolved making it rather complicated for experimental and numerical investigations. In early reviews[1-4] general mechanisms related to wave breaking problems are well described. However previous emphasis lies on the phenomenological characteristics of breaking wave. Thus this review summarizes the recent experimental and numerical advances of the studies of air entrainment bubble distribution energy dissipation capillary effect and so on. 展开更多
关键词 wave breaking energy DISSIPATION air ENTRAINMENT and VOID FRACTION BUBBLE and DROPLET size distribution capillary effects
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Advances in capillary electro-chromatography 预览
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作者 Zhenkun Mao Zilin Chen 《药物分析学报:英文版》 CAS CSCD 2019年第4期227-237,共11页
Capillary electrochromatography (CEC) is a micro-scale separation technique which is a hybrid between capillary electrophoresis (CE) and liquid chromatography (LC). CEC can be performed in packed, monolithic and open-... Capillary electrochromatography (CEC) is a micro-scale separation technique which is a hybrid between capillary electrophoresis (CE) and liquid chromatography (LC). CEC can be performed in packed, monolithic and open-tubular columns. In recent three years (from 2016 to 2018), enormous attention for CEC has been the development of novel stationary phases. This review mainly covers the development of novel stationary phases for open-tubular and monolithic columns. In particular, some biomaterials attracted increasing interest. There are no significant breakthroughs in technology and principles in CEC. The typical CEC applications, especially chiral separations are described. 展开更多
关键词 CAPILLARY ELECTROCHROMATOGRAPHY OPEN-TUBULAR COLUMN Monolithic COLUMN Novel stationary PHASES Separation MODES
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Eff ects of the Imbibition Ability of Extinguishant in Pulverized Coals 预览
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作者 Liyan Liu Haoshuang Gong +3 位作者 Xin Shi Dong Lv Wei Tan Guorui Zhu 《天津大学学报:英文版》 EI CAS 2019年第1期45-51,共7页
The imbibition ability of extinguishant is an important factor influencing the extinguishing eff ect for smoldering fi re in pulverized coals. The coal particle size, bulk compactness, and aqueous solution properties ... The imbibition ability of extinguishant is an important factor influencing the extinguishing eff ect for smoldering fi re in pulverized coals. The coal particle size, bulk compactness, and aqueous solution properties signifi cantly aff ect the imbibition ability of extinguishment. This work aims to reveal the influence of the properties of pulverized coals and aqueous solution on the imbibition ability of extinguishant for smoldering fi re through experiments and capillary theories. The imbibition height and rate were adopted to evaluate the imbibition ability of extinguishment. The results showed that a relatively small bulk compactness and a fi ne coal particle size negatively influenced the extinguishing process dominantly because of its high surface energy and low wettability. An additive was used to adjust the properties of aqueous solution. The liquid with a larger surface tension, a smaller contact angle, and a lower viscosity induced a better imbibition ability of extinguishment. 展开更多
关键词 Pulverized COAL SMOLDERING fire IMBIBITION ABILITY CAPILLARY theories
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