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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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Feasibility of compacted attapulgite/diatomite amended clayey soils as gas barrier materials
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作者 Heng Zhuang Wei-Yi Xia +5 位作者 Jia-Ming Wen Min Wang Ying-Zhen Li Ning-Jun Jiang Konstantin S.Rodygin Yan-Jun Du 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3707-3717,共11页
Compacted clay liners are extensively used as barriers to control the upward diffusion of vapors of volatile or semi-volatile organic contaminants released from unsaturated contaminated soils at industrycontaminated s... Compacted clay liners are extensively used as barriers to control the upward diffusion of vapors of volatile or semi-volatile organic contaminants released from unsaturated contaminated soils at industrycontaminated sites.This study aimed to investigate the gas diffusion barrier performance of compacted clayey soils amended with three agents including attapulgite and diatomite individually,and attapulgite/diatomite mixture.The properties including water retention,volumetric shrinkage,gas diffusion,and unconfined compressive strength were evaluated through a series of laboratory tests of amended compacted clayey soils.The results demonstrate that the decrease in volume proportions of interaggregate pores leads to an increase in unconfined compressive strength(qu).Both hydrophilic groups and microstructures of attapulgite and diatomite result in an increase in water retention percent(Wt)of compacted clayey soil specimens after amendment regardless of the type of agent or initial water content(w0).Furthermore,the ratio of the gas diffusion coefficient(De)to the gas diffusion coefficient in the air(Da)was significantly reduced owing to a decrease in volume proportions of inter-aggregate pores,hydrophilic group,and microstructures of attapulgite and diatomite.Scanning electron microscope analyses revealed that rod-shaped attapulgite filled the inter-aggregate pores formed by clay particles,whereas the disc-shaped diatomite particles,characterized by micropores,failed to obstruct the interaggregate pores due to their larger particle size.Mercury intrusion porosimetry(MIP)analyses showed a reduction in pore volume in the inter-aggregate pores,leading to a reduction in the total pore volume for both the attapulgite and attapulgite/diatomite mixture amended clays,which is in accordance with the scanning electron microscope(SEM)results.The findings are pertinent to the practical application of compacted clay liners as gas barriers against the upward migration of volatile or semi-volatile organic contaminants at contaminated sites. 展开更多
关键词 Compacted clay liner Attapulgite/diatomite mixture Diffusion barrier water retention
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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 Jingyu REN Nan JIANG +3 位作者 Kefeng SHANG Na LU Jie LI Yan WU 《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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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 horizontal well bottom water reservoir semi-permeable barrier 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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The critical rate of horizontal wells in bottom-water reservoirs with an impermeable barrier 被引量:7
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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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Using Visual MODFLOW Model to Assess the Efficiency of Subsurface Barrier Wall for Groundwater Flow Regulation and Reduction of Saline Intrution 被引量:1
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作者 Nguyen Minh Khuyen Doan Van Long +3 位作者 Nguyen Tien Bach Tang Huu Dong Bui Cong Du Dang Dinh Phuc 《Journal of Environmental Science and Engineering(A)》 2021年第3期104-115,共12页
Barrier walls effectively store water,regulate underground flows,improve exploitable reserves and prevent saltwater intrusion.The effectiveness of the underground barrier wall depends not only on the hydrogeological s... Barrier walls effectively store water,regulate underground flows,improve exploitable reserves and prevent saltwater intrusion.The effectiveness of the underground barrier wall depends not only on the hydrogeological structure,the technical parameters of the wall but also on the layout scheme of the exploitation well system.The results showed that in natural conditions,the ground water level upstream of the barrier wall rose in the presence of a barrier wall.In wells located downstream of high barrier walls,the water level decreased.The amount of underground current flowing into the sea decreased,the annual average value of the whole region decreased was 316 m3/day and night.In presence of a wall,both the water level and the amount of evaporation increased.The average increase in evaporation volume during the calculation period of ten thousand days with walls was 4.114 m3/d.So in presence of a wall,the amount of water that can be exploited increases by the total amount of evaporation plus the decrease in discharge to the sea and is equal to 4,424 m3/d.In the exploitation condition,if the water level in the presence of wall is kept as low as in the absence of wall,the exploitation flow will increase to about 4,400 m3/day and night.From the calculated water level values when there is a wall and without a wall,we can see that if the exploitation flow in presence of a wall and in the absence of wall is the same,the water level drop at the calculated observation wells upstream of the wall will decrease from 0.21 m to 3.97 m.The condition of effective exploitation of the wall depends on the mining scheme.The exploitation scheme is reasonable,the exploitation flow of the wells does not exceed the allowable flow so as not to cause the drying of the aquifer at the location of the well.The upstream area of the wall reflects quite clearly as the Total dissolved solids content in observation wells upstream of the wall at the end of the calculation time is significantly reduced compared to that without the wall,ranging from 69 mg/L to 5,629 mg/L.In the presence of a wall,the water level of observation wells upstream of the wall is higher than that of without a wall from 0.10 m to 0.74 m. 展开更多
关键词 Subsurface barrier wall store water regulate underground flows.
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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
In this investigation, a clean, atomic economic and direct synthesis of oxygenates (methanol, ethanol) form water and methane via dielectric-barrier discharge was developed at room temperature and under atmospheric pr... In this investigation, a clean, atomic economic and direct synthesis of oxygenates (methanol, ethanol) form water and methane via dielectric-barrier discharge was developed at room temperature and under atmospheric pressure. The effect of discharge voltage on this process was studied. The results showed that the conversion of water can be as high as 7%, the selectivity of methanol and ethanol can be as high as 100%. 展开更多
关键词 OXYGENATES METHANE water dielectric-barrier discharge.
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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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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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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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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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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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基于熵权TOPSIS的黄河流域甘肃段水资源承载力评价 被引量:2
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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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考虑透水效应的泥石流柔性防护网耦合分析方法
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作者 余志祥 骆泓锦 +3 位作者 张丽君 骆丽茹 金云涛 赵雷 《岩土工程学报》 EI CAS CSCD 北大核心 2024年第8期1695-1702,共8页
针对柔性防护网在黏性泥石流通过时的透水效应问题,在柔性环连网等效薄膜有限单元(FEM)的基础上,结合S-ALE和Ergun公式的欧拉-拉格朗日耦合算法,提出了Structured-ALE-FEM耦合算法(简称S-A-F方法),实现了考虑透水效应的泥石流柔性防护... 针对柔性防护网在黏性泥石流通过时的透水效应问题,在柔性环连网等效薄膜有限单元(FEM)的基础上,结合S-ALE和Ergun公式的欧拉-拉格朗日耦合算法,提出了Structured-ALE-FEM耦合算法(简称S-A-F方法),实现了考虑透水效应的泥石流柔性防护网耦合分析。结合USGS的泥石流柔性防护模型试验,开展了泥石流柔性防护全过程动力学分析,并与试验结果进行了对比分析。研究表明:提出的耦合方法可再现泥石流冲击、爬高及渗透堆积的全过程;与试验相比,泥石流堆积高度和堆积宽度的最大误差分别为11.9%和10.3%,泥石流浆体通过量最大差量为3.2%;柔性防护网关键部件动力响应与试验相比,右侧拉锚绳、左侧拉锚绳及网片最大变形量时程曲线误差分别为3.2%,16.4%,14.4%。与不考虑阻水效应的两种理论算法相比,S-A-F方法在泥石流冲击力峰值和泥石流浆体通过量准确度较同类其他方法提升了4.69%和17.50%。提出的S-A-F耦合方法可用于黏性泥石流柔性防护工程的设计计算。 展开更多
关键词 泥石流 柔性防护网 S-ALE 薄膜等效 透水
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基于反应性水汽高阻隔环烯烃共聚物复合膜的制备和多性能优化
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作者 顾宁 刘子萱 +5 位作者 吴栋创 王妍 何欢 姚俊儒 曹杨 孙友谊 《功能材料》 CAS CSCD 北大核心 2024年第10期10151-10156,10188,共7页
针对现有柔性高分子复合膜水汽阻隔性能偏低,且水汽透过率、机械力学强度和光学透过率等多性能难以同时优化的矛盾问题,开发了一种新型氧化镁掺杂环烯烃共聚物复合膜(MgO/COC)。探索了MgO含量对复合膜力学性能、热性能、疏水性能以及水... 针对现有柔性高分子复合膜水汽阻隔性能偏低,且水汽透过率、机械力学强度和光学透过率等多性能难以同时优化的矛盾问题,开发了一种新型氧化镁掺杂环烯烃共聚物复合膜(MgO/COC)。探索了MgO含量对复合膜力学性能、热性能、疏水性能以及水蒸气阻隔性能的影响。研究结果表明,MgO在COC复合膜中具有良好的分散性。当1%(质量分数)MgO掺杂COC时,接触角达到最高(106.8°),表明MgO/COC复合膜具有良好的疏水特性。复合膜的水蒸气阻隔性能比纯COC膜提高了63.1%,最小水汽透过率达到0.21 g/(m^(2)·d),是目前公开报道掺杂型高分子复合膜水汽透过率的最低值。优异的水汽阻隔性能归因于MgO与水汽反应特性形成了氢氧化镁,同时氢氧化镁具有优异水汽阻隔性能。该复合膜双机制水汽阻隔特性为食品包装和医药包装的水汽阻隔设计提供新的思路。 展开更多
关键词 水汽阻隔 COC 氧化镁 复合膜 反应型
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应用测井资料小波变换与伪成像技术精细划分深部隔夹层
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作者 邵才瑞 王萌 +3 位作者 昌伦杰 王开宇 张福明 王超 《新疆石油地质》 CAS CSCD 北大核心 2024年第5期611-621,共11页
隔夹层影响流体渗流,控制油水及剩余油分布,深层取心成本高,常规测井曲线分辨率低且薄互层信号模糊,深部隔夹层识别难度大。通过对关键井岩心研究,得出了隔夹层敏感测井曲线及其响应特征,采用小波分解和重构,对常规敏感测井曲线进行了... 隔夹层影响流体渗流,控制油水及剩余油分布,深层取心成本高,常规测井曲线分辨率低且薄互层信号模糊,深部隔夹层识别难度大。通过对关键井岩心研究,得出了隔夹层敏感测井曲线及其响应特征,采用小波分解和重构,对常规敏感测井曲线进行了高分辨率处理,降低了邻层平滑效应,突出了薄层界面测井响应特征,薄层识别分辨率提高了近1倍。综合利用隔夹层地层倾角矢量模式和伪成像特征,确立了深部隔夹层判识划分方法,应用实例表明,该方法可精细识别隔夹层,相比常规方法,隔夹层辨识能力显著提升,井间小层对比精度提高38%,解释了油水界面倾斜问题,得出了剩余油分布规律。 展开更多
关键词 测井资料 深部隔夹层 小波变换 地层倾角 伪成像 油水界面
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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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国内外地铁挡水技术和装置综述
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作者 程泽农 杨新征 +1 位作者 柏赟 冯旭杰 《都市快轨交通》 北大核心 2024年第5期29-35,共7页
为提高地铁内涝应急处置能力,对国内外地铁挡水技术和装置进行研究。针对地铁车站出入口、风亭风井、正线、车辆基地等地铁内涝风险点,系统梳理国内外地铁挡水技术和挡水装置,分析地铁挡水装备的适用场景以及优缺点;探讨地铁挡水装置在... 为提高地铁内涝应急处置能力,对国内外地铁挡水技术和装置进行研究。针对地铁车站出入口、风亭风井、正线、车辆基地等地铁内涝风险点,系统梳理国内外地铁挡水技术和挡水装置,分析地铁挡水装备的适用场景以及优缺点;探讨地铁挡水装置在成本经济性、智能化与自动化以及可持续性等问题上面临的挑战,提出结构优化与材料改进、多功能挡水装置、智能化与自动化控制、绿色技术与可持续发展等方面的建议。研究结果表明:不同挡水装置应用场景不同,应针对不同风险点位以及涝水特点正确选择挡水装置;地铁常规挡水装置应用广泛,技术相对成熟;新型技术在自动化方面有所突破,可以节省人力,提高应急可靠度。研究成果旨在为地铁挡水装置的设计、安装和应用提供参考,为保障地铁系统的安全运行和有效应对地铁内涝提供技术支撑。 展开更多
关键词 轨道交通 地铁内涝 挡水技术 挡水装置 挑战与展望
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堰塞湖应急抢险大功率虹吸技术及装备研发
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作者 翁怡萌 蔡耀军 +1 位作者 王小波 栾约生 《人民长江》 北大核心 2024年第4期38-43,共6页
为了满足堰塞湖应急抢险对大流量虹吸装备研发制造的需求,首先分析了堰塞湖应急抢险大功率虹吸技术装备的应用场景与研发难点,对装备系统进行了针对性总体设计,介绍了设计中采用的水力流场流态优化、数字智能化调控、工业模块化装配等... 为了满足堰塞湖应急抢险对大流量虹吸装备研发制造的需求,首先分析了堰塞湖应急抢险大功率虹吸技术装备的应用场景与研发难点,对装备系统进行了针对性总体设计,介绍了设计中采用的水力流场流态优化、数字智能化调控、工业模块化装配等关键技术。该装备包含潜水整流单元、液气交换单元、智能监控单元三部分。其中整流单元采用群孔并联射流的管道进流方式,智能监控单元采取数据分布式管理,为系统的稳态运行提供数据支撑。该新装备具有运行稳定、泄水量大、安装简便、启动快速等优点,泄流能力可达3500~15000 m^(3)/h,不仅可以用于堰塞湖应急排水抢险,也可以用于其他领域的大流量输排水作业。 展开更多
关键词 堰塞湖 虹吸应急泄流 水力优化 智能化调控 输排水
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