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Study on physical simulated test in controlling the sea water(salt water) intrusion through fresh water barrier
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《Global Geology》 1998年第1期34-34,共1页
关键词 intrusion through fresh water barrier Study on physical simulated test in controlling the sea water salt water
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Jonzac Thermal Spring Water Reinforces Skin Barrier Function of Human Skin and Presents a Soothing and Regenerating Effect
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作者 Valérie Cauche Coralie Martineau +3 位作者 Giuseppe Percoco Marie Reynier Stéphanie Scalvino Laurent Peno-Mazzarino 《Journal of Cosmetics, Dermatological Sciences and Applications》 2023年第4期247-268,共22页
The skin is a formidable physical and biological barrier which communicates continuously with the outside of the body. And the stratum corneum, the outermost layer of human epidermis, plays a central role in the inter... The skin is a formidable physical and biological barrier which communicates continuously with the outside of the body. And the stratum corneum, the outermost layer of human epidermis, plays a central role in the interaction between the cutaneous tissue and the external environment. The horny layer, and more generally the whole skin layers, avoid the penetration of harmful exogenous agents, produce molecules named anti-microbial peptides which impact the composition of the cutaneous microbiota, regulate the internal corporal temperature, avoid the water loss from the inside of the body and constitute an incredible efficient anti-oxidant network. Nevertheless, nowadays, the skin is more and more solicited by the different elements of the cutaneous exposome, including atmospheric pollution and solar radiations, which can cause a dramatic acceleration of the skin ageing process. As a consequence, due to the multifunctional protective role of the skin, during the recent decade the cosmetic industry invested massively in the development of new raw materials and end-products (dermo-cosmetics) able to preserve an optimal state of the skin regarding the external environment. Based on their physical-chemical properties thermal spring waters, which are extremely rich in inorganics ions, are interesting and powerful candidates to be part, as integral component, of new efficient dermo-cosmetic formulations dedicated to protect the skin from the external stimuli. The aim of the present work was to investigate and characterize the activity of Jonzac thermal spring water on the skin. Using different models, we proved for the first time that Jonzac thermal spring water reinforces the barrier function of the skin by modulating the expression of key markers including filaggrin and human beta defensin 2 on ex vivo human skin. The ex vivo and in vivo hydration activity, by Raman spectroscopy and corneometry respectively, has been also demonstrated. We have also shown that Jonzac thermal spring water ameliorates significantly the cutaneous microrelief in vivo. To conclude, we characterize the soothing effect of Jonzac thermal spring water by the analysis of histamine release in Substance P treated skin explants and by measuring the redness of the skin following UV exposure of the skin in vivo. We observed that both parameters decreased following a preventive treatment of the skin with Jonzac thermal spring water. Taken together our results indicate that Jonzac thermal spring water is a promising and powerful dermo-cosmetic which can be used to preserve an optimal state of the cutaneous tissue. 展开更多
关键词 Jonzac Thermal Spring water Skin barrier Function Soothing Effect Regenerating Effect Skin Hydration Isotonicity Dermo-Cosmetics Ex Vivo Explants
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The critical rate of horizontal wells in bottom-water reservoirs with an impermeable barrier 被引量:6
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作者 Yue Ping Du Zhimin +1 位作者 Chen Xiaofan Liang Baosheng 《Petroleum Science》 SCIE CAS CSCD 2012年第2期223-229,共7页
Barrier impacts on water cut and critical rate of horizontal wells in bottom water-drive reservoirs have been recognized but not investigated quantitatively. Considering the existence of impermeable barriers in oil fo... Barrier impacts on water cut and critical rate of horizontal wells in bottom water-drive reservoirs have been recognized but not investigated quantitatively. Considering the existence of impermeable barriers in oil formations, this paper developed a horizontal well flow model and obtained mathematical equations for the critical rate when water cresting forms in bottom-water reservoirs. The result shows that the barrier increases the critical rate and delays water breakthrough. Further study of the barrier size and location shows that increases in the barrier size and the distance between the barrier and oil-water contact lead to higher critical rates. The critical rate gradually approaches a constant as the barrier size increases. The case study shows the method presented here can be used to predict the critical rate in a bottom-water reservoir and applied to investigate the water cresting behavior of horizontal wells. 展开更多
关键词 Horizontal well bottom-water reservoir barriers critical rate cresting
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How Do Water Filled Traffic Barriers Shake a Suspension Bridge? 被引量:1
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作者 Guanni Qu Tianai Yue +1 位作者 Xiaoyu Zhang Shibiao Wei 《Fluid Dynamics & Materials Processing》 EI 2022年第3期591-608,共18页
The present study stems from the realization that the general problem relating to the analysis of wind-induced vibrations in suspension bridges still requires significant attention.Sidewalk railings,overhaul tracks,an... The present study stems from the realization that the general problem relating to the analysis of wind-induced vibrations in suspension bridges still requires significant attention.Sidewalk railings,overhaul tracks,and deflectors are known to largely affect such dynamics.Here,the influence of a row of water-filled traffic barriers on the response of a sample suspension bridge is investigated numerically.It is shown that the existence of water barriers causes flow separation and non-negligible vortices with respect to the condition with no water barriers.The vortex shedding frequency at the far end is around 41.30 Hz,relatively close to the real vibration frequency.It is also shown how different incoming angles of attack can change the flow field around the bridge cross-section and the vortex detachment frequency. 展开更多
关键词 Suspension bridge water filled traffic barriers computational fluid dynamics vortex shedding frequency attack angle VIBRATION
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Direct Synthesis of Oxygenates from Water and Methane via Dielectric-barrier Discharge 被引量:1
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作者 BaoWeiWANG GenHuiXU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第7期779-780,共2页
关键词 OXYGENATES METHANE water dielectric-barrier discharge.
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Critical parameters of horizontal well influenced by semi-permeable barrier in bottom water reservoir 被引量:6
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作者 乐平 杜志敏 +2 位作者 陈小凡 朱苏阳 贾虎 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1448-1455,共8页
It is well-known that barriers have a significant impact on the production performance of horizontal wells developed in a bottom water drive reservoir. In most cases, reservoir barriers are semi-permeable. Based on pr... It is well-known that barriers have a significant impact on the production performance of horizontal wells developed in a bottom water drive reservoir. In most cases, reservoir barriers are semi-permeable. Based on previous research on impermeable reservoir barrier, a mathematical flow model was derived for a horizontal well of a bottom water drive reservoir with a semi-permeable barrier. Besides, analytical equations were also presented to calculate critical parameters, such as production rate,pressure and potential difference. The effects of barrier, well and reservoir parameters on our model results were further investigated.The results show that the larger the barrier size is or the higher the barrier location is, the higher the critical production rate and potential difference of a horizontal well are. When the barrier permeability equals the formation permeability or the barrier width equals zero, the critical production rates converge to the values same to that of the case with no barrier. When the barrier permeability equals zero, the problem is regarded as a case of impermeable barrier. This model can be applied to predicting horizontal wells' critical production parameters in reservoirs with semi-permeable barriers. 展开更多
关键词 关键参数 底水油藏 屏障 底水驱油藏 储层参数 模型推导 生产速率 渗透性
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Influence of Water Vapor on the Isothermal Oxidation Behavior of Thermal Barrier Coatings
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作者 Chungen ZHOU, Jingsheng YU, Shengkai GONG and Huibin XUDepartment of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第1期38-40,共3页
The oxidation of specimens with thermal barrier coating (TBC) consisted of nickel-base superalloy, low-pressure plasma sprayed Ni-28Cr-6AI-0.4Y (wt pct) bond coating and electron beam physical vapor deposited 7.5 wt p... The oxidation of specimens with thermal barrier coating (TBC) consisted of nickel-base superalloy, low-pressure plasma sprayed Ni-28Cr-6AI-0.4Y (wt pct) bond coating and electron beam physical vapor deposited 7.5 wt pct yttria stabilized zirconia (YSZ) top coating was studied at 1050℃ respectively in flows of 02, and mixture of O2 and 5%H2O under atmospheric pressure. The thermal barrier coating has relatively low oxidation rate at 1050℃ in pure O2. Oxidation rate of thermal barrier coating in the atmosphere of O% and 5%H2O is increased The oxidation kinetics obeys almost linear law after long exposure time in the presence of 5% water vapor. Oxide formed along the interface between bond coat and top coat after oxidation at 1050℃ in pure O2 consisted of Al2O3, whereas interfacial scales formed after oxidation at 1050℃ in a mixture of O2 and 5%H2O were mainly composed of Ni(AI,Cr)2O4,NiO and AI2O3. It is suggested that the effect of water vapor on the oxidation of the NiCrAlY coating may be attributed to the increase in Ni and Cr ions transport in the oxides. 展开更多
关键词 OXIDATION water vapor Thermal barrier coating
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Beneficial Effect of a Thermal Spring Water on the Skin Barrier Recovery after Injury: Evidence for Claudin-6 Expression in Human Skin
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作者 Francine Joly Cécile Gardille +1 位作者 Eric Barbieux Luc Lefeuvre 《Journal of Cosmetics, Dermatological Sciences and Applications》 2012年第4期273-276,共4页
Aim: To evaluate the possible advantages of dermo-cosmetic products formulated with thermal spring water instead of deionized water. We studied the effect of a dermo-cosmetic product on skin barrier recovery after inj... Aim: To evaluate the possible advantages of dermo-cosmetic products formulated with thermal spring water instead of deionized water. We studied the effect of a dermo-cosmetic product on skin barrier recovery after injury. In one test the product was formulated with de-ionized water and again using the identical product formulated with thermal spring water. Study Design/Methods: Stratum corneum of human skin explants was removed (and not removed for the control) with an ether/acetone mixture. A cosmetic product, either formulated with de-ionized or thermal spring water, was then topically applied on the explants. After a 5-day incubation period, epidermal expression of aquaporine-3, filaggrin, claudin-4 and claudin-6 was studied by using immunohistochemical techniques. Results: The formulation containing de-ionized water seemed to act on the epidermal expression of filaggrin and claudin-4. When thermal spring water was used to make the formulation, we noted that this expression was greatly enhanced. The formulation containing thermal spring water also acted to increase aquaporin-3 and claudin-6 expression. Conclusion: The use of thermal spring water in cosmetic formulations would appear to contribute to the cosmetic product’s efficacy. It was also interesting to note that this study revealed claudin-6 expression in human skin for the first time. 展开更多
关键词 KERATINOCYTE Differentiation THERMAL Spring water barrier Repair CLAUDIN-4 Claudin-6 Aquaporine 3 FILAGGRIN
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Evaluation of trans-ferulic acid degradation by dielectric barrier discharge plasma combined with ozone in wastewater with different water quality conditions 被引量:2
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作者 任景俞 姜楠 +3 位作者 商克峰 鲁娜 李杰 吴彦 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第2期68-77,共10页
In this study, dielectric barrier discharge plasma and ozone(O_3) were combined to synergistically degrade trans-ferulic acid(FA), and the effect of water quality on FA degradation was studied. The results showed that... In this study, dielectric barrier discharge plasma and ozone(O_3) were combined to synergistically degrade trans-ferulic acid(FA), and the effect of water quality on FA degradation was studied. The results showed that 96.9% of FA was degraded after 40 min treatment by the plasma/O_3 process. FA degradation efficiency increased with the p H values. The presence of suspended solid and humic acid inhibited FA degradation. FA degradation efficiency increased as the water temperature increased to 30 °C. However, the further increase in water temperature was adverse for FA degradation. Effects of common inorganic ions on FA degradation were also investigated. The addition of Cl^- inhibited the FA degradation, whileCO_3^(2-) had both negative and positive influences on FA degradation.NO_3^- andSO_4^(2-) did not have significant effect on FA degradation. Fe^(3+)and Cu^(2+)benefited FA degradation through the Fenton-like and catalytic ozonation reactions. 展开更多
关键词 dielectric barrier DISCHARGE OZONE trans-ferulic acid water quality INORGANIC ions
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Study on the Generation Characteristics of Dielectric Barrier Discharge Plasmas on Water Surface
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作者 刘文正 李传辉 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第1期26-31,共6页
A new contact glow discharge electrode employed in this study. Because of the strong field the electrode and the water surface, glow discharge on the surface of water was designed and strength in the small air gap for... A new contact glow discharge electrode employed in this study. Because of the strong field the electrode and the water surface, glow discharge on the surface of water was designed and strength in the small air gap formed by plasmas were generated and used to treat waste water. The electric field distribution of the designed electrode model was simulated by MAXWELL 3D~ simulation software, and the discharge parameters were measured. Through a series of experiments, we investigated the impact of optimal designs, such as the dielectric of the electrode, immersion depths, and curvature radii of the electrode on the generation characteristics of plasmas. In addition, we designed an equipotential multi-electrode configuration to treat a Methyl Violet solution and observe the discoloration effect. The experimental and simulation results indicate that the designed electrodes can realize glow discharge with a relative low voltage, and the generated plasmas covered a large area and were in stable state. The efficiency of water treatment is improved and optimized with the designed electrodes. 展开更多
关键词 water surface PLASMA electrode model dielectric barrier discharge electric field
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Plasma-Catalytic Decomposition of 2,4-Dichlorophenol in a Dielectric Barrier Discharge with a Vermiculite ZiO2 Composite
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作者 Grigoriy I. Gusev Andrey A. Gushchin +3 位作者 Vladimir I. Grinevich Ekaterina M. Baburina Ekaterina S. Severgina Natalya E. Gordina 《Advances in Chemical Engineering and Science》 2023年第4期318-335,共18页
The paper presents comparative kinetic characteristics of the decomposition of 2,4-dichlorophenol in a dielectric barrier discharge and a combined plasma-catalytic process. Vermiculite containing 5% zirconium was used... The paper presents comparative kinetic characteristics of the decomposition of 2,4-dichlorophenol in a dielectric barrier discharge and a combined plasma-catalytic process. Vermiculite containing 5% zirconium was used as a catalyst. The destruction processes of 2,4-DCP proceed efficiently, the degree of decomposition increases in the combined plasma-catalytic process by a factor of 1.33 and reaches 80%. The experimental results were processed according to the first-order kinetic law (R<sup>2</sup> > 0.97), according to which the effective constants (0.36 ± 0.04) and (0.51 ± 0.03) s<sup>-1</sup> and the decomposition rates of 2,4-DCP (106 and 123 μmol/l·s) when treating model solutions without a catalyst and with vermiculite + Zr 5%, respectively, and the energy costs are 0.012 and 0.017 molecules/100eV. The main decomposition products present in the solution have been determined to be carboxylic acids, aldehydes, the contribution of which does not exceed 2%, as well as chloride ions, and in the gas phase they are carbon dioxide and molecular chlorine (the share of which does not exceed 1.5% of total chlorine content in the system). 展开更多
关键词 2 4-Dichlorophenol Dielectric barrier Discharge PLASMA Oxygen Treatment water Treatment Catalyst ZIRCONIUM VERMICULITE
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DBD等离子体耦合BiOI催化材料降解苯甲羟肟酸的特性与机制
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作者 董冰岩 李贞栋 +3 位作者 王佩祥 涂文娟 谭艳雯 张芹 《化工进展》 EI CAS CSCD 北大核心 2024年第3期1565-1575,共11页
常温常压下,以苯甲羟肟酸(BHA)为处理对象建立了介质阻挡放电(DBD)等离子体催化体系。研究了放电参数对等离子体降解BHA的影响规律,对水热合成法制备的催化材料进行了系列表征分析,考察了各因素对BHA降解的影响,分析了DBD等离子体耦合... 常温常压下,以苯甲羟肟酸(BHA)为处理对象建立了介质阻挡放电(DBD)等离子体催化体系。研究了放电参数对等离子体降解BHA的影响规律,对水热合成法制备的催化材料进行了系列表征分析,考察了各因素对BHA降解的影响,分析了DBD等离子体耦合催化剂降解BHA过程中总有机碳(TOC)、pH、∙OH自由基等的变化,通过液相色谱-质谱联用仪分析了降解反应过程的中间产物并探讨了BHA的降解机理。表征结果显示合成的BiOI具有高比表面积、高孔体积、高纯度的介孔纳米片微球,且DBD可以改变催化剂的晶型和结构,具有更高的催化性能。降解性能结果表明,峰值电压、鼓气量等对BHA降解率有很大影响;BHA浓度为80mg/L、体积1000mL,在峰值电压24kV,频率7500Hz,鼓气量30L/min条件下,添加0.3g BiOI催化剂与DBD等离子体耦合效果最好,相对于单一DBD体系,BHA降解率由78.8%提高到88.2%。降解机理分析可知,∙OH是BHA降解的重要活性物质,在等离子体催化作用下,BHA被氧化开环,转化为苯甲酸和乙醇酸等中间体,最终生成H_(2)O和CO_(3)^(2-)等。 展开更多
关键词 介质阻挡放电 等离子体 废水 降解 矿化率 催化剂
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基于CT扫描的重构土壤孔隙结构及其对水盐运移影响
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作者 李华焜 郑刘根 +3 位作者 陈永春 李兵 陶鹏飞 李浩 《煤田地质与勘探》 EI CAS CSCD 北大核心 2024年第4期120-127,共8页
煤矸石是煤矿沉陷区土地充填复垦的关键材料。但煤矸石质地较为粗糙,持水性较差,煤矸石重构土壤的孔隙结构和水盐运移都会与原状土壤产生一定差异。为研究煤矸石充填土壤孔隙结构变化以及对水盐运移的影响,利用CT扫描技术和图像分析方法... 煤矸石是煤矿沉陷区土地充填复垦的关键材料。但煤矸石质地较为粗糙,持水性较差,煤矸石重构土壤的孔隙结构和水盐运移都会与原状土壤产生一定差异。为研究煤矸石充填土壤孔隙结构变化以及对水盐运移的影响,利用CT扫描技术和图像分析方法,分析覆土、泥矸混合、矸石与原状土样品的孔隙结构差异,同时设计一种室内重构土壤水盐运移模拟装置,通过在实验装置不同深度布设传感器,连续记录重构土壤剖面水分与盐分的运移情况。结果表明,在原状土、覆土、泥矸混合与矸石4份样品中,矸石样品孔隙率高于其他样品,达到8.299%,导致其持水能力较差;泥矸混合样品小孔隙占比高,达到58.73%,孔隙连通性较差,缺乏水分运移通道,导致层间障碍带的形成;覆土样品与原状土样品孔隙结构非常接近。在土柱模拟实验中,土壤盐分含量随水分运移而变化,各土壤层含盐量均先升高后降低,入渗结束后,表层土壤完成脱盐,深层土壤呈现积盐状态。在注水6d内,土壤层含盐量均先降低后升高,50cm土壤层变化幅度最大,为38.34%。深层土壤盐分借助毛管力作用向上运移,表层土壤含盐量逐渐回升。由于层间障碍带的存在,矸石层水分与盐分均难以向上运移,其含量逐渐下降。研究结果可为沉陷区土地充填复垦和矿区生态修复提供参考。 展开更多
关键词 煤矸石 重构土壤 孔隙结构 CT扫描 层间障碍 水盐运移
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富水砂卵石地层深基坑降水特性及涌水量研究
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作者 杨恒星 周玉乐 +3 位作者 王子琪 张跃飞 李玉秦 梁斌 《浙江水利水电学院学报》 2024年第1期12-19,共8页
以洛阳市周山大道下穿开元大道路口明挖深基坑工程为依托,分析各降水参数改变对渗流场分布与降水效率的影响。通过Midas GTS NX有限元软件,模拟分析不同降水参数下降水井抽排地下水情况,同时建立了标准状态下涌水量特征曲线,并针对非标... 以洛阳市周山大道下穿开元大道路口明挖深基坑工程为依托,分析各降水参数改变对渗流场分布与降水效率的影响。通过Midas GTS NX有限元软件,模拟分析不同降水参数下降水井抽排地下水情况,同时建立了标准状态下涌水量特征曲线,并针对非标准状态提出涌水量修正方法。结果表明:除地层渗透系数改变地下水流速外,其他参数均会导致流网形态发生改变,与阻隔效应耦合后将间接影响降水速率。另外,通过工程实例验证考虑止水帷幕阻隔作用后的深基坑涌水量预测公式及其修正函数具有合理性,可应用于砂卵石地层深基坑降水工程。 展开更多
关键词 砂卵石地层 深基坑降水 止水帷幕 阻隔效应 基坑涌水量修正
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双硅酸镱环境障涂层的高温水氧腐蚀机理研究
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作者 胡祥鹏 蒋文昊 李彪 《材料保护》 CAS CSCD 2024年第3期63-69,共7页
陶瓷基复合材料构件在航空发动机燃气环境中面临严重的水氧腐蚀退化问题,在构件表面采用环境障涂层进行热防护是提高陶瓷基复合材料部件的高温性能、延长其使用寿命的有效措施。环境障涂层的高温稳定性对部件的结构完整性具有重要影响... 陶瓷基复合材料构件在航空发动机燃气环境中面临严重的水氧腐蚀退化问题,在构件表面采用环境障涂层进行热防护是提高陶瓷基复合材料部件的高温性能、延长其使用寿命的有效措施。环境障涂层的高温稳定性对部件的结构完整性具有重要影响。为了探明环境障涂层在高温下的水氧腐蚀失效行为和机理,针对大气等离子喷涂(APS)Yb_(2)Si_(2)O_(7)/莫来石/硅体系的环境障涂层系统,开展了其在1350℃、90%(体积分数)H_(2)O-10%O_(2)水/氧蒸汽环境中的静态高温水氧腐蚀试验,采用XRD、SEM、EDS等材料表征分析手段,研究涂层在高温静态水氧腐蚀环境中的失效行为,获得EBCs涂层微观结构及物相在腐蚀过程中的演变规律,揭示EBCs涂层的失效机理。结果表明:表面的Yb_(2)Si_(2)O_(7)与环境中的氧化剂(主要为水)反应生成挥发性物质Si(OH)_(4),导致Yb_(2)Si_(2)O_(7)被不断消耗,莫来石层中的Si元素与Yb_(2)Si_(2)O_(7)层中的稀土元素发生互扩散,使得高温化学反应过程和机理十分复杂;在经历500 h腐蚀后,涂层出现鼓包脱落而失效。 展开更多
关键词 环境障涂层 高温 水氧腐蚀
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引水枢纽旋转式浮筒拦排的研究及工程设计
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作者 孟昭辰 段晓芳 +1 位作者 林广志 王相峰 《海河水利》 2024年第2期108-111,共4页
引水枢纽首部的漂浮物影响水工建筑物和水质,漂浮物高效治理问题亟待解决。以拦、导、排为基本思路,对水库治漂浮槽进行了改造,设计出旋转式浮筒拦排。对旋转式浮筒拦排在不同来水流量、不同安装角度和不同漂浮物的情况进行了试验分析... 引水枢纽首部的漂浮物影响水工建筑物和水质,漂浮物高效治理问题亟待解决。以拦、导、排为基本思路,对水库治漂浮槽进行了改造,设计出旋转式浮筒拦排。对旋转式浮筒拦排在不同来水流量、不同安装角度和不同漂浮物的情况进行了试验分析和讨论,结果表明:来水流量越大导排漂效果越好;合理的安装角度对驱动浮筒的转动起到一定作用;一定质量和运动速度的漂浮物对导漂效果起着积极作用。针对改扩建工程和新建工程分别提出导排漂设计方案。本研究可为引水枢纽漂浮物的治理起到积极推动作用,为其他类型建筑物的导排漂设计提供参考。 展开更多
关键词 引水枢纽 拦污排漂 旋转式浮筒 工程设计
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纤维性能对纸张水蒸气阻隔性能的影响
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作者 胡小莉 张雪 +3 位作者 张红杰 侯磊磊 程芸 田超 《中国造纸》 CAS 北大核心 2024年第1期38-50,共13页
本研究利用不同种类、不同程度打浆处理及硅烷化改性的纸浆纤维,制备物化性能不同的纸张,调控纸张的三维孔隙结构,从纤维的物理性能和化学疏水改性对纸张结构影响的角度,探讨纤维性能(打浆度、纤维长度及分布、保水值、纤维形貌和亲/疏... 本研究利用不同种类、不同程度打浆处理及硅烷化改性的纸浆纤维,制备物化性能不同的纸张,调控纸张的三维孔隙结构,从纤维的物理性能和化学疏水改性对纸张结构影响的角度,探讨纤维性能(打浆度、纤维长度及分布、保水值、纤维形貌和亲/疏水性等)对纸张水蒸气阻隔性能的影响。结果表明,纸张的水蒸气阻隔性能受纤维打浆度和亲/疏水性的影响较大。测试条件(23±0.5)℃、相对湿度(50±1)%时,打浆度从13.5°SR增至90°SR的未漂化学针叶木浆制备的定量60 g/m^(2)纸张的水蒸气透过率从954.5 g/(m^(2)·d)降低至93.77 g/(m^(2)·d);测试条件为(23±0.5)℃、相对湿度(75±1)%时,疏水改性纤维纸张比未改性纤维纸张的水蒸气透过率降低了11.6%,纸张的水蒸气透过率受疏水改性纤维配抄比例的影响较大。 展开更多
关键词 纤维形态 润湿性能 水蒸气阻隔性能 三维孔隙结构
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基于熵权TOPSIS的黄河流域甘肃段水资源承载力评价
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作者 张帆 尹萌 张金霞 《人民黄河》 CAS 北大核心 2024年第4期79-85,共7页
为评价黄河流域甘肃段水资源承载力,以黄河流域甘肃段4个二级分区为研究对象,初选20个评价指标,利用信息敏感性和相关性分析法剔除敏感性较低和相关性较高的7个指标,最终确定13个评价指标。从系统角度将指标分为水资源、社会、经济、生... 为评价黄河流域甘肃段水资源承载力,以黄河流域甘肃段4个二级分区为研究对象,初选20个评价指标,利用信息敏感性和相关性分析法剔除敏感性较低和相关性较高的7个指标,最终确定13个评价指标。从系统角度将指标分为水资源、社会、经济、生态环境4个子系统,利用熵权法与TOPSIS模型结合的方法计算综合得分,并利用障碍因子诊断模型分析4个二级分区的水资源承载力障碍因子。结果表明:空间维度上,黄河流域甘肃段水资源承载力存在空间差异性,龙羊峡以上分区水资源承载力最高,龙羊峡—兰州分区与兰州—河口镇分区水资源承载力次之,龙门—三门峡分区水资源承载力最低;时间维度上,除龙羊峡以上分区外其余3个二级分区水资源承载力均有缓慢上升趋势;人均水资源量、产水模数、人均供水量、人口密度、城镇化率及生态环境用水率是影响黄河流域甘肃段水资源承载力的主要障碍因子,建议优化水资源配置、调整用水结构、促使经济发展与水资源承载力相匹配等,以提升及保持黄河流域甘肃段水资源承载力。 展开更多
关键词 水资源承载力 熵权法 TOPSIS模型 障碍度模型 黄河流域甘肃段
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水资源视角下的近零能耗“寒地热屏障系统”建构新思维——从Emory大学的Water Hub项目说开去 被引量:1
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作者 赵宏宇 王俊旗 《建筑与文化》 2018年第3期55-57,共3页
基于目前北方寒地城市普遍遇到的水资源短缺问题、冬季绿色基础设施生态功能丧失以及城市供水排水压力大三大关键性问题,从恒温恒湿的环境控制、分散式水处理和设施小型化的角度阐述了Water Hub等国内外案例给我们带来的启发。提出了在... 基于目前北方寒地城市普遍遇到的水资源短缺问题、冬季绿色基础设施生态功能丧失以及城市供水排水压力大三大关键性问题,从恒温恒湿的环境控制、分散式水处理和设施小型化的角度阐述了Water Hub等国内外案例给我们带来的启发。提出了在北方寒地建设集全天候保持生态性、近零能耗、多功能性于一体的"寒地热屏障系统",并对其概念进行了深入剖析,阐述了"寒地热屏障系统"应该具备的五大内涵和五大特征,以期利用空间手法为北方寒地城市解决干旱、水污染、生态景观问题提供一定的借鉴。 展开更多
关键词 海绵城市 北方寒冷地区 热屏障系统 water HUB
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基于ANSYS Workbench的水马结构拓扑优化设计
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作者 曾祥坤 许健升 +1 位作者 蔡仁烨 植柏槺 《农业装备与车辆工程》 2024年第5期140-144,共5页
针对水马结构存在的材料利用率低、生产成本高等问题,使用SolidWorks建立三维模型,利用ANSYS Workbench中的Design Exploration模拟水马在车辆正面碰撞时的应力应变情况,以优化水马结构为目标进行拓扑优化设计,建立以变密度法保留质量... 针对水马结构存在的材料利用率低、生产成本高等问题,使用SolidWorks建立三维模型,利用ANSYS Workbench中的Design Exploration模拟水马在车辆正面碰撞时的应力应变情况,以优化水马结构为目标进行拓扑优化设计,建立以变密度法保留质量百分比为响应约束的数学模型。优化后水马结构的质量和体积比原有结构下降了约10%,在同等碰撞条件下等效应力和等效弹性应变均减少超过20%,总变形量减少47.59%,为类似优化实验提供参考。 展开更多
关键词 水马 数学模型 拓扑优化 变密度法
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