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991.
《International Journal of Hydrogen Energy》2020,45(35):17174-17190
The study investigated the synergistic effects of rGO and Pt over TiO2 for the HER via artificial photosynthesis under UVB and visible light irradiation. The introduction of glycerol and industrial wastewater to the system as sacrificial reductants signifies that the major reaction pathway is photocatalytic partial water splitting. The material characterizations revealed successful heterojunction formation and provided insight into chemistry behind the activity of the photocatalysts. Amongst various combinations of rGO on TiO2, 1GNT exhibited an HER yield five times that of bare TiO2 under UVB light. Addition of Pt led to the formation of a strong Schottky barrier at the heterojunction and consequently boosted HER performance. 1P0.5 GT presented the highest of 28.5 mmol g−1 h−1 with glycerol and 9.6 mmol g−1 h−1 with wastewater under UVB light respectively. For both binary and ternary photocatalysts, the HER performances dwindled under visible light irradiation, accentuating the insufficient activation of the TiO2. In addition, 1PT outperformed all the other photocatalysts thereby elucidating the impression that rGO and Pt does not work well together in enhancing HER despite quenching the exciton recombination rate of TiO2 significantly. The role of pH in the synthesis and the experiments has been discussed. Finally, the underlying mechanisms in the photodeposition and photoreformation have been proposed. 相似文献
992.
Water soluble chitosan (WSC) was prepared by hydrolysing chitosan using α-amylase. The degradation was monitored by WSC recovery and the WSC structure was characterised by Fourier transform infrared spectroscopy. The optimal hydrolysis conditions were found to be at pH 5, 50 °C, 20 mg α-amylase in the reaction solution, with a reaction time of 4 h. Under these conditions, the average molecular weight of chitosan decreased to 730 Da. The resulting products were composed of chitooligosaccharides of DP 3–7. The hydrolysate was neutralised with 1 M NaOH, filtered, concentrated to 16% (w/v), precipitated with five volumes of ethanol to one volume of the concentrated hydrolysate solution, and dried at 60 °C for 3 h to yield a white powder. The WSC content of the product and the yield were 96.2% and 91.2% (w/w), respectively. 相似文献
993.
以大豆分离蛋白(SPI)为主要基质的成膜溶液加入其它成分(阿魏酸、淀粉、明胶、乙醇)后调pH、热处理后铺板干燥,揭膜,在相对湿度为65%的室温环境下平衡48h后测定膜的颜色,水蒸气透性(WVP)、抗拉强度(聪)、断裂伸长率(E)等;并研究这些膜用作方便面汤料包装时的应用特性。结果表明,乙醇对膜的以上特性都有显著影响,表现为黑度降低,透明度增加,WVP显著降低,断裂伸长率增加,但TS有所下降。成膜溶液pH为中性的加100mg阿魏酸的膜在沸水中的溶解情况最理想,1min完全溶解,用其包装汤料,煮或泡后该膜对汤的外观和口味均无不良影响。 相似文献
994.
Two flow field designs, a new multi-inlet design and a conventional serpentine design, for a PEMFC together with relative humidity (RH) and porosity of the gas diffusion layer (GDL) are studied in relation to net water production using a 3-dimensional computational fluid dynamics simulation. The results show that (1) with increasing GDL porosity, discharged water in the serpentine design slightly increases, because accumulated water decreases, whereas discharged water in the multi-inlet design decreases due to a reduction of generated water; (2) although fuel cell power performance improves as RH increases, net water production decreases in both designs, because more water is accumulated; and (3) comparatively higher power and net water production are observed with the multi-inlet design, owing to uniform distributions of reactant gas and water. It is determined that, for net water production without compromising power production, input water should be decreased and, for higher cell performance, flow field design like multi-inlet design should be developed. 相似文献
995.
996.
高聚物降滤失剂改性磺化酚醛树脂是由磺化酚醛树脂与腐殖酸在一定条件下磺化共聚制成。对改性磺化酚醛树脂在淡水、盐水钻井液中的抗盐性、抗温性及降滤失性进行了评价。改性磺化酚醛树脂的最优加量为5%,它与其它增粘剂配合使用,抗盐达15%。改性磺化酚醛树脂抗温达200℃,随温度升高降滤失能力增强,温度为150℃时改性磺化酚醛树脂的降滤失效果最佳,改性磺化酚醛树脂的降滤失性能优于SLSP,高温时其钻井液形成的滤饼薄而致密。 相似文献
997.
带隔板底水油藏油井见水时间预报公式 总被引:16,自引:8,他引:16
李传亮 《大庆石油地质与开发》1997,16(4):49-50
本提出了带隔板底水油藏油井见水时间的理论预报公式,它在底水油藏的生产管理中将起到十分重要的指导作用。 相似文献
998.
牛栏江泵站机组为国内目前单机容量最大的高扬程大流量离心泵组,采用立式布置同步电动机驱动设计,泵组轴向高度尺寸大,电动机顶部与水泵进水管底部高度大约为18 m。如此大型的水泵机组,无法在制造厂内进行水泵与电动机组装后的无水动平衡试验,而要在工地现场进行无水状态下的动平衡试验在国内属于首次;无水试验因泵站引水系统处于空管状态,无法为地下厂房内机组提供试验所需技术供排水,因此试验技术中的供水系统是本次泵组试验能否安全进行的关键。经分析研究,决定采用临时供水与原技术供水方案相结合的方式。运行效果表明,该方式满足了大型地下厂房水泵机组的无水动平衡试验对泵组技术供水的要求;大型地下泵站开展无水动平衡试验是完全可行的。试验成果可为类似大型地面厂房泵组无水试验提供技术参考。 相似文献
999.
集对分析是处理不确定性问题的新方法,它通过联系度展示了研究对象间关系的详细结构。方法原理简单,使用方便,能解决很多实际水文水资源问题。简要介绍了集对分析的基本原理,重点分析了集对分析在水文水资源分析计算、预测和评价中的应用研究进展,展望了集对分析在水文水资源领域的研究目标、内容和拟解决的关键问题。 相似文献
1000.
The irrigation in regions of brackish groundwater in many parts of the world results in the rise of the water-table very close to the groundsurface. The salinity of the productive soils is therefore increased. A proper layout of the ditch-drainage system and the prediction of the spatio-temporal variation of the water table under such conditions are of crucial importance in order to control the undesirable growth of the water-table. In this paper, an approximate solution of the nonlinear Boussinesq equation has been derived to describe the water-table variations in a ditch-drainage system with a random initial condition and transient recharge. The applications of the solution is discussed with the help of a synthetic example.Notations
a
lower value of the random variable representing the initial water-table height at the groundwater divide
-
a+b
upper value of the random variable representing the initial water-table height at the groundwater divide
-
h
variable water-table height measured from the base of the aquifer
-
K
hydraulic conductivity
-
L
half width between ditches
-
m
0
initial water-table height at the groundwater divide
-
N(t)
rate of transient recharge at time t
-
N
0
initial rate of transient recharge
-
P
N
0/K
-
S
Specific yield
-
t
time of observation
-
t
0
logarithmic decrement of the recharge function
-
T
Kt/SL
-
x
distance measured from the ditch boundary
-
X
x/L
-
Y
h/L
- Y
mean of Y
- Y
Variance of Y 相似文献