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Lowering ash slagging and fouling tendency of high-alkali coal by hydrothermal pretreatment 预览
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作者 Mingshun Yang Qiang Xie +3 位作者 Xin Wang He Dong Hao Zhang Chunqi Li 《矿业科学技术学报:英文版》 CSCD 2019年第3期521-525,共5页
High-alkali species in coal are notorious for causing ash slagging and fouling incidents.In this paper,four high-alkali coals were individually subject to hydrothermal pretreatment(HTP),within a batch-type autoclave a... High-alkali species in coal are notorious for causing ash slagging and fouling incidents.In this paper,four high-alkali coals were individually subject to hydrothermal pretreatment(HTP),within a batch-type autoclave at 300 -C for 1 h,and the treated coals were analyzed,along with the oxygen-containing functional groups determined by Fourier transform infrared spectrometer(FT-IR).Then the alkali species and other components in the coal ash were quantified by X-ray fluorescence(XRF)for evaluating the ash slagging and fouling tendency.Apart from this,FactSage was adopted to simulate the occurrence and transformation of alkali species during coal thermal conversion ending at various temperatures.The findings indicate that the treated coals are superior to the parent ones in terms of certain remarkable changes via HTP.The moisture,oxygen and sulfur of the hydrothermally treated coals decline obviously,while the calorific value rises sharply.HTP could reduce the alkali species to less than 2%(%,by weight,equivalent to Na2O in dry ash),with a maximum removal ratio of 88.9%,lowering the ash slagging and fouling tendency.The proposed mechanism of HTP was that the alkali species in coal matrix became released due to the breakage of the coal functional groups and micropores during HTP. 展开更多
关键词 HYDROTHERMAL PRETREATMENT High-alkali COAL ASH SLAGGING and fouling tendency Lowering FactSage
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The effects of prosodic phrase boundary on the pitch lowering of downstep and focus
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作者 GUO Jingyi HUANG Xianjun +1 位作者 LüShinan YANG Jinchen 《声学学报:英文版》 CSCD 2019年第3期340-352,共13页
The effects of prosodic phrase(PP)boundary on the pitch lowering of downstep and focus,as well as the domains of them were investigated in Chinese Putonghua,by using designed sentences which consist of two prosodic ph... The effects of prosodic phrase(PP)boundary on the pitch lowering of downstep and focus,as well as the domains of them were investigated in Chinese Putonghua,by using designed sentences which consist of two prosodic phrases(i.e.,PP1,PP2).The results showed that:(1)The PP boundary blocked the downstep effect in the preceding phrase,indicating that PP is the domain of downstep.(2)The post-focus F0 lowering effect in PP1 spread across the PP boundary and lower the FO contour of PP2.If there is a downstep effect in PP2,the postboundary compression effect of the prior focus will accumulate with the downstep,producing further lowered contour.Therefore,the domain of focus is an intonational phrase(IP).(3)When there is one contrastive focus in each phrase,the outstanding pitch reset elicited by the second focus will block the FO lowering effect of PP1 onto PP2,and the two foci are realized independently. 展开更多
关键词 DOMAIN The EFFECTS of prosodic PHRASE BOUNDARY on the PITCH lowering of downstep and FOCUS
古代经典名方中的药对运用思维探讨 预览
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作者 魏佳明 朱俊平 +2 位作者 刘瑞连 李雅 郭志华 《天津中医药》 CAS 2019年第7期659-661,共3页
基于古代经典名方目录(第一批)对其中的药对运用思维进行探讨,从药对与治法、药对与四气、药对与五味、药对与升降浮沉、药对与归经、药对与药物毒性等6个角度加以列举分析,以期进一步挖掘古代经典名方丰富的内在价值并指导临床药对的... 基于古代经典名方目录(第一批)对其中的药对运用思维进行探讨,从药对与治法、药对与四气、药对与五味、药对与升降浮沉、药对与归经、药对与药物毒性等6个角度加以列举分析,以期进一步挖掘古代经典名方丰富的内在价值并指导临床药对的运用。 展开更多
关键词 经典名方 药对 临床应用 治法 四气五味 升降浮沉 归经 药物毒性
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Effect of lipid lowering mixture on blood lipid metabolism, LDL oxidation susceptibility and blood viscosity and coagulation in experimental hyperlipidemia rats
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作者 Xue-Bing Luan Fu-Chen Zhang +2 位作者 Zhi-Yuan Weng Yu Zhang Liang Ma 《海南医科大学学报(英文版)》 2019年第4期17-20,共4页
Objective:To investigate the effect of lipid lowering mixture on blood lipid metabolism, LDL oxidative susceptibility and blood viscosity and coagulation in experimental hyperlipidemia rats.Method: Select 60 male Wist... Objective:To investigate the effect of lipid lowering mixture on blood lipid metabolism, LDL oxidative susceptibility and blood viscosity and coagulation in experimental hyperlipidemia rats.Method: Select 60 male Wistar rats were randomly divided into six groups, ten rats in each group were recorded as low as lipid-lowering mixture, high dose group and simvastatin group, model group and control group. Patients in control group were treated with basic feed for feeding, other groups of rats are used high fat diet were fed to establish hyperlipidemia rat model, in the process of modeling and prophylactically, determination of rats after 10 weeks of lipid metabolism and susceptibility of LDL to oxidation and blood viscosity concentration coagulation state.Result: Antioxidant capacity of the model group rat's serum LDL-C decreased significantly, and simvastatin group and three groups of lipid-lowering mixture group rats serum LDL antioxidant capacity were significantly enhanced;and high lipid mixture, LDL antioxidant ability in middle dose group rats were significantly higher than those of the Jiangzhi Decoction low dose group rats (P<0.05). Lipid mixture of high, middle dose group rats of EET and ETA P, ETA B (high, medium and low shear), IED, HCT, the role of the IEA was significantly higher in Jiangzhi Decoction low dose group rats (P<0.05 or P<0.05).Conclusion:Lipid-lowering mixture on experimental hyperlipidemia rats blood lipid metabolism and blood viscosity concentration coagulation state has a good regulatory role, and lipid-lowering mixture on blood lipid and blood flow abnormalities lipid-lowering mixture can also play a good regulation and therapeutic effect. 展开更多
关键词 HYPERLIPEMIA LIPID lowering MIXTURE BLOOD LIPID METABOLISM BLOOD COAGULATION state LIPID carrier protein
浅谈“掤、沉、蓄、发”技术体系在太极拳推手中的运用 被引量:1
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作者 王洪平 《中华武术(研究)》 2018年第9期39-40,31共3页
本文采用现场观摩、专家访谈、文献资料及逻辑分析等方法,对太极推手中的'掤、沉、蓄、发'的技术体系,在教学训练中进行分析研究。本研究表明:'掤、沉、蓄、发'技术体系的运用对提高太极推手的技术水平有很好的指导和... 本文采用现场观摩、专家访谈、文献资料及逻辑分析等方法,对太极推手中的'掤、沉、蓄、发'的技术体系,在教学训练中进行分析研究。本研究表明:'掤、沉、蓄、发'技术体系的运用对提高太极推手的技术水平有很好的指导和引领作用,对太极拳套路的演练水平也有借鉴和导向作用。 展开更多
关键词 太极推手 太极拳
慢性乙型肝炎患者丙氨酸氨基转移酶正常值上限下调必要性初步探讨 预览
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作者 涂文辉 朱伟君 +2 位作者 钱峰 张继明 朱传武 《世界华人消化杂志》 CAS 2018年第30期1765-1771,共7页
目的初步探讨慢性乙型肝炎(hepatitis B virus, HBV)患者目前采用的丙氨酸氨基转移酶正常值上限(upperlimit of normal, ULN)下调的必要性.方法收集非活动性乙肝表面抗原(hepatitis B surfaceantigen, HBsAg)携带者及接受抗病毒... 目的初步探讨慢性乙型肝炎(hepatitis B virus, HBV)患者目前采用的丙氨酸氨基转移酶正常值上限(upperlimit of normal, ULN)下调的必要性.方法收集非活动性乙肝表面抗原(hepatitis B surfaceantigen, HBsAg)携带者及接受抗病毒治疗慢性HBV患者715例, 病毒DNA均低于检测值下限, 其中非活动性HBsAg携带者组57例(携带组), 慢性HBV抗病毒治疗组455例(肝炎组), ALT低于2 ULN经肝穿活检后抗病毒治疗组203例(其中ALT〈1 ULN 133例, ALT1-2 ULN 70例)(肝穿组). 收集患者年龄、性别、体重、肝功能、血糖、血脂、血常规、乙肝病毒感染血清学标志物、乙肝病毒DNA定量、甲胎蛋白、肝胆脾B超等相关数据. 肝穿组收集肝组织炎症分级、纤维化分期及抗病毒治疗1年后肝功能数据.结果全部患者(n=715)ALT水平中位数为19IU/L,95%百分位数为31.2IU/L(95%CI:30-34IU/L),95%百分位数男性为34IU/L(95%CI:31-35IU/L),女性为26.2IU/L(95%CI:25-30IU/L).肝穿组患者抗病毒治疗后ALT值下降显著,中位数由37IU/L降至23IU/L,具显著统计学差异(F=111.497,P=0.000).根据4种不同ALT正常值上限,肝脏显著炎症(≥G2)的检出率分别为0,38.78%,63.27%和84.69%.以ROC分析ALT对肝组织学显著炎症的评估价值,AUC值(Az)为0.751,对ALT与肝组织学炎症程度作Logistic回归分析,P值为0.331.结论目前应用的ALT正常值上限对评估慢性HBV是偏高的,似乎存在下调的必要性. 展开更多
关键词 乙型肝炎 慢性 组织学 炎症 丙氨酸氨基转移酶 正常值上限 下调
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High-voltage trench-gate hole-gas enhancement-mode HEMT with multi-conduction channels
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作者 Chao YANG Xiaorong LUO +2 位作者 Siyu DENG Fu PENG Bo ZHANG 《中国科学:信息科学(英文版)》 CSCD 2018年第6期178-187,共10页
In this paper, we present a novel high-voltage low on-resistance trench-gate (TG) hole-gasenhancement-mode (E-mode) high-electron mobility transistor (HEMT) with multi-conduction channels(MCs) and investigate ... In this paper, we present a novel high-voltage low on-resistance trench-gate (TG) hole-gasenhancement-mode (E-mode) high-electron mobility transistor (HEMT) with multi-conduction channels(MCs) and investigate its mechanism using simulations. This device features a repetitive A1N/CaN hetero-junction unit and a CaN/A10.26Ga0.74N hetero-junction. Its source and drain are located on the same sideof the metal-insulator-semiconductor (MIS) TG, and the source is located beside the gate. During operation,first, 2-D electron gas (2DEG) forms MCs at multiple A1N/GaN hetero-interfaces. These MCs result inultra-low specific on-resistance (Ron,sp) and improved transconductance (gm). Second, 2-D hole gas (2DHG)is induced at the CaN/A10.26Ga0.74N hetero-interface to prevent electrons from being injected from thesource to the MCs. As such, E-mode operation is realized, which exceeds the performance of the conven-tional E-mode method by depleting the 2DEG under the gate. Third, in the off-state, 2DHG and 2DEGare depleted into negative and positive charges, respectively, thereby forming the polarization junction. Thisdepletion region is extended due to the electric field (E-field) modulation effect by the polarization junction,thereby achieving an enhanced breakdown voltage (BV). Fourth, the drain-induced barrier lowering (DIBL)effect is significantly suppressed, which ensures a high BV and low leakage current. Additionally, due tothe unique source location, the TG-MC-HEMT is smaller than the conventional MIS AIGaN/GaN HEMT(Con-HEMT). The BV of the TG-MC-HEMT is 604 V and the Ron.sp value can be as small as 0.38 mΩ.cm2. 展开更多
关键词 multi-conduction channels 2-D HOLE GAS polarization-junction HIGH-VOLTAGE low specific ON-RESISTANCE drain-induced barrier lowering effect.
Impact of strained silicon on the device performance of a bipolar charge plasma transistor
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作者 Sangeeta Singh 《半导体学报:英文版》 EI CAS CSCD 2018年第12期120-126,共7页
In this manuscript we analyze a unique approach to improve the performance of the bipolar charge, plasma transistor (BCPT)by introducing a strained Si/SixGe1-x layer as the active device region.For charge plasma reali... In this manuscript we analyze a unique approach to improve the performance of the bipolar charge, plasma transistor (BCPT)by introducing a strained Si/SixGe1-x layer as the active device region.For charge plasma realization different metal work-function electrodes are used to induce n^+and p^+regions on undoped strained silicon-on-insulator (sSOI or SixGe1-x)to realize emitter,base,and collector regions of the BCPT.Here, by using a calibrated 2-D TCAD simulation the impact of a Si mole fraction x (in SixGe1-x)on device performance metrics is investigated.The analysis demonstrates the band gap lowering with decreasing Si content or effective strain on the Si layer,and its subsequent advantages.This work reports a significant improvement in current gain,cutoff frequency,and lower collector breakdown voltage (BVCEO)for the proposed structure over the conventional device.The effect of varying temperature on the strained Si layer and its implications on the device performance is also investigated.The analysis demonstrates a fair device-level understanding and exhibits the im- mense potential of the SixGe1-x material as the device layer.In addition to this,using extensive 2-D mixed-mode TCAD simulation,a considerable improvement in switching transient times are also observed compared to its conventional counterpart. 展开更多
关键词 BIPOLAR CHARGE PLASMA TRANSISTOR (BCPT) strained Si layer MOLE fraction band gap lowering current gain (β) CUTOFF frequency (fT) collector breakdown voltage (BVCEO)
浅析涉水单壁钢围堰施工工艺 预览
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作者 孙二龙 韩存 《现代制造技术与装备》 2018年第8期172-172,174共2页
在当前的基础设施施工中,涉水桥梁工程所占比重越来越大,深水基础施工成为桥梁工程至关重要关键因素,现有围堰方式主要有土围堰、拉森钢板桩围堰、管桩围堰、单壁钢围堰、双壁钢围堰,根据现场情况(水深、需入强风化岩层)及经济角度考... 在当前的基础设施施工中,涉水桥梁工程所占比重越来越大,深水基础施工成为桥梁工程至关重要关键因素,现有围堰方式主要有土围堰、拉森钢板桩围堰、管桩围堰、单壁钢围堰、双壁钢围堰,根据现场情况(水深、需入强风化岩层)及经济角度考虑,与拉森钢板桩、管桩围堰、土围堰及双壁钢围堰相比具有安全性、快速性、环保、经济等优点。 展开更多
关键词 单壁钢围堰 焊接 下放 封底
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Total-Ionizing-Dose-Induced Body Current Lowering in the 130 nm PDSOI I/O NMOSFETs
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作者 Xiao-Nian Liu Li-Hua Dai +1 位作者 Bing-Xu Ning Shi-Chang Zou 《中国物理快报:英文版》 SCIE CAS CSCD 2017年第1期90-93,共4页
The body current lowering effect of 13Onto partially depleted silicon-on-insulator (PDSOI) input/output (I/O)n-type metal-oxide-semiconductor field-effect transistors (NMOSFETs) induced by total-ionizing dose is... The body current lowering effect of 13Onto partially depleted silicon-on-insulator (PDSOI) input/output (I/O)n-type metal-oxide-semiconductor field-effect transistors (NMOSFETs) induced by total-ionizing dose is observedand analyzed. The decay tendency of current ratio of body current and drain current Ib/Id is also investigated.Theoretical analysis and TCAD simulation results indicate that the physical mechanism of body current loweringeffect is the reduction of maximum lateral electric field of the pinch-off region induced by the trapped charges inthe buried oxide layer (BOX). The positive charges in the BOX layer can counteract the maximum lateral electricfield to some extent. 展开更多
关键词 Total-Ionizing-Dose-Induced BODY Current Lowering the 130 NM PDSOI I/O NMOSFETS
长输管道含弯管下沟施工工艺探讨
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作者 郑明高 《施工技术》 北大核心 2016年第S2期234-236,共3页
长输管道施工在平原和丘陵地区采用沟上焊接然后下沟的施工工艺,能够有效提高施工效率,降低安全风险。从测量的角度,先计算管道下沟的偏移量,指导管沟的开挖,保证管道下沟的质量,并就测量放线、布管、管沟开挖等工序的操作要点进行说明。
关键词 长输管道 弯管 下沟
新型全回转浮式起重机的人字架放倒设计 预览 被引量:2
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作者 张炳发 季圣国 李朝阳 《起重运输机械》 2016年第11期32-34,共3页
全回转浮式起重机的结构特点使其最大高度超出水面很多,影响作业范围,甚至绕道远航。全回转浮式起重机的人字架放倒设计有效地解决了这一难题。文中在分析目前浮式起重机所使用的两种人字架放倒方法的基础上,提出了一种全新的人字架... 全回转浮式起重机的结构特点使其最大高度超出水面很多,影响作业范围,甚至绕道远航。全回转浮式起重机的人字架放倒设计有效地解决了这一难题。文中在分析目前浮式起重机所使用的两种人字架放倒方法的基础上,提出了一种全新的人字架放倒技术,不仅适用于新建起重机的设计,而且也可以应用于原有起重机的改造,结合实例介绍人字架放倒前后整台起重船的高度变化。 展开更多
关键词 全回转浮式起重机 人字架 放倒
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US and Global Governance of Nuclear Security: from Guiding to Leading 预览
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作者 Fan Jishe 《当代世界:英文版》 2016年第2期22-23,共2页
<正>Global Governance of Nuclear Security:US guiding Role As early as at the beginning of the Cold War,the US realized the risks of nuclear security being that a country with nuclear materials may secretly trans... <正>Global Governance of Nuclear Security:US guiding Role As early as at the beginning of the Cold War,the US realized the risks of nuclear security being that a country with nuclear materials may secretly transport nuclear weapons into the US and launch an attack.Aimed at lowering the risks,the US has committed itself to pushing the international community in building the nuclear nonproliferation systems,founding the International Atomic Energy Agency,strengthening the monitoring of nu- 展开更多
关键词 Nuclear COMMITTED lowering LAUNCH FOUNDING Atomic itself BEGINNING approval governance
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导热材料在降低直流电动机主极温升的应用 被引量:1
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作者 安彩霞 王鑫 《煤矿机械》 2016年第8期134-136,共3页
通过在直流电机主极线圈与机座之间填充不同材料进行温升对比试验,找到了一种可操作性强,降温效果显著的导热材料,辅以合理的主极装配工艺,有效解决主极线圈温升高问题。
关键词 导热材料 降低 电机 温升
银杏叶制剂临床应用回顾与评价
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作者 程光其 《实用中医内科杂志》 2015年第1期162-164,共3页
银杏叶制剂治疗心脑血管疾病、老年痴呆,增加动脉血流量,效果良好。运用分析化学、植物化学与药理学对银杏叶制剂进一步研究,将银杏叶中有效成分高效提取与分离,研发新型银杏叶产品,为各领域提供更广阔的市场。基于此回顾性分析银杏叶... 银杏叶制剂治疗心脑血管疾病、老年痴呆,增加动脉血流量,效果良好。运用分析化学、植物化学与药理学对银杏叶制剂进一步研究,将银杏叶中有效成分高效提取与分离,研发新型银杏叶产品,为各领域提供更广阔的市场。基于此回顾性分析银杏叶制剂在临床疾病治疗中的效果。 展开更多
关键词 银杏叶制剂 抗氧化 降脂 降压 调节内分泌
African Americans,hypertension and the renin angiotensin system 预览
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作者 Sandra F Williams Susanne B Nicholas +1 位作者 Nosratola D Vaziri Keith C Norris 《世界心脏病学杂志:英文版(电子版)》 2014年第9期878-889,共12页
African Americans have exceptionally high rates of hypertension and hypertension related complications. It is commonly reported that the blood pressure lowering efficacy of renin angiotensin system(RAS) inhibitors is... African Americans have exceptionally high rates of hypertension and hypertension related complications. It is commonly reported that the blood pressure lowering efficacy of renin angiotensin system(RAS) inhibitors is attenuated in African Americans due to a greater likelihood of having a low renin profile. Therefore these agents are often not recommended as initial therapy in African Americans with hypertension. However, the high prevalence of comorbid conditions, such as diabetes, cardiovascular and chronic kidney disease makes treatment with RAS inhibitors more compelling. Despite lower circulating renin levels and a less significant fall in blood pressure in response to RAS inhibitors in African Americans, numerous clinical trials support the efficacy of RAS inhibitors to improve clinical outcomes in this population, especially in those with hypertension and risk factors for cardiovascular and related diseases. Here, we discuss the rationale of RAS blockade as part of a comprehensive approach to attenuate the high rates of premature morbidity and mortality associated with hypertension among African Americans. 展开更多
关键词 AMERICANS African RENIN cardiovascular lowering ATTENUATED HYPERTENSIVE prevalence CIRCULATING MEDICATION
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Effects of low protein diet supplemented with ketoacids on local renin-angiotensin system enzyme activities and podocytes loss in patients with diabetic nephropathy
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作者 谷立杰 《中国医学文摘:内科学分册(英文版)》 2014年第3期186-187,共2页
Objective To explore the effects of low-protein diet supplemented with ketoacids on podocytes as well as local RAS in the kidney of patients with diabetic nephropathy.Methods A total of 61 patients with T2DN and CKD ... Objective To explore the effects of low-protein diet supplemented with ketoacids on podocytes as well as local RAS in the kidney of patients with diabetic nephropathy.Methods A total of 61 patients with T2DN and CKD stages 3-4 were included.All the patients were randomly divided into two groups:low protein group(0.6g·kg BW-1·d-1and 30 kcal·kg BW-1·d-1,LPD) 展开更多
关键词 supplemented CREATININE RENIN nephrin urinary AMINATION albumin urine lowering explained
How does stiffness of trabecular meshwork affect outflow resistance in human eyes?
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作者 Fan Yuan Lucinda J.Camras +2 位作者 W.Daniel Stamer David Epstein Pedro Gonzalez 《医用生物力学》 CAS CSCD 北大核心 2013年第S1期86-88,共3页
Purpose Ocular hypertension is the primary risk factor for development of glaucoma and the only modifiable endpoint<sup>[1,2]</sup>.Clinical trials involving thousands of patients have shown consistently ... Purpose Ocular hypertension is the primary risk factor for development of glaucoma and the only modifiable endpoint<sup>[1,2]</sup>.Clinical trials involving thousands of patients have shown consistently that lowering intraocular pressure(IOP)in those with glaucoma,whether or not their IOP is above normal,slows vision loss.IOP elevation is the result of diminished outflow facility in the conventional outflow pathway;and the highest resistance to aqueous humor outflow resides in the juxtacanalicular tissue(JCT)layer of trabecular meshwork(TM)and the inner wall of Schlemm’s canal(SC).However,mechanisms of outflow facility decrease in glaucomatous eyes remain to be determined. 展开更多
关键词 OUTFLOW TRABECULAR glaucoma INTRAOCULAR facility consistently STIFFNESS CANAL lowering ENDPOINT
大吨位、短行程液压同步顶升下放系统的研制 预览 被引量:1
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作者 周平 《起重运输机械》 2012年第5期 63-66,共4页
介绍了重庆朝天门大桥主桥移梁施工概况,详细论述了大吨位、短行程液压同步顶升下放系统的设计,指出了该系统的技术突破和技术创新,这对大吨位、短行程、刚性物体的同步顶升和下放施工有指导意义。
关键词 液压系统 同步 顶升 下放
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阿钢324m^3高炉中修停炉实践 预览
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作者 孟凡靖 《黑龙江冶金》 2011年第1期 55,57,共2页
阿钢1#324m^3高炉已安全服役7年,采用空料线打水停炉,整个过程安全、顺利、快速停炉,为高炉中修创造了有利条件。
关键词 高炉 停炉 降料线
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