几种喷头的布水性能对比试验

开发了具有自主知识产权的玻璃防火分隔专用喷头。通过对自行研制的专用喷头与WS窗玻璃喷头及国内普通侧喷喷头的冷态布水情况开展对比试验,对在不同压力、与玻璃之间不同安装距离的情况下,3种喷头在玻璃上的布水喷洒、水在玻璃上的分布情况、流量系数K值等进行对比分析研究。结果表明,自行研制的玻璃防火分隔专用喷头的喷洒效果显著,能达到甚至超过WS窗玻璃喷头的喷洒效果,而普通侧喷喷头的喷洒效果最差。

高大空间场所自动喷水灭火系统布水性能试验研究

为研究工作压力、安装高度等对喷头布水性能的影响,以K161喷头为研究对象,在安装高度分别为8m、12m和18m,工作压力分别为0.05MPa、0.10MPa、0.15MPa和0.20MPa的条件下,共计开展了12次喷头布水性能试验。试验结果显示,喷头集水率受安装高度的影响较小,在相同工作压力下,12m和18m高度下实测喷水强度基本一致,但随着工作压力的增加,喷头集水率逐渐增加,与理论计算值趋于一致,但均小于理论计算值;工作压力越高,喷头布水均匀性越差。

信息熵在人工湿地布水性能评价中的应用探析

研究了信息熵应用于垂直流人工湿地布水性能评价中的可行性。结果表明:其评价结果不受时间和单次布水总量的影响,能有效将布水面积与基质底部各位置接水量的均匀性结合起来,评价结果更具有实际意义。对于单一粒径5~10 mm、连通孔隙率25.3%~32.9%的粘结型模块化基质而言,布水性能随布水管单孔进水流量的增大而提高得越来越慢,运行初期布水管单孔最佳进水流量为600 mL/min;布水性能随基质深度的增加而提高,在深度为70 cm以后布水性能提高不再明显。

喷头的布水性能还是提出均匀度指标好——对GB5135的补充意见

众所周知,无论是洒水喷头还是泡沫喷头,在它的整个保护面积内的介质密度分布都不是绝对均匀的。为了描述喷头的喷洒特性,人们采用了介质分布曲线或分布图,其中最普遍采用的是以喷射半径R为横座标,以沿喷射半径方向上集水盒的接水深度h为纵座标,或以沿喷射半径方向上喷头喷射到单位面积上的介质量,即喷洒强度P为纵座标。

新型火冰灭火剂喷洒布水性研究

通过实验数据阐述新型火冰灭火剂在自动喷水灭火系统中的喷洒布水性能。对比水、A型火冰灭火剂、AB型火冰灭火剂的喷洒质量分布情况,得出:AB型火冰灭火剂与水相近,可直接用于自动喷水灭火系统或水-泡沫灭火两用系统中;A型火冰灭火剂则不可直接使用。

高吸水性非织造布的研制

介绍了合成聚丙烯酸接枝淀粉浆液并使其在非织造布上形成吸水树脂 ,从而得到高吸水性非织造布的实验过程 ,对接枝单体的比例、交联条件、浸轧量及非织造布本身材质等因素对吸水非织造布吸水性能的影响进行了讨论。

微波技术制备吸水性无纺布

讨论了微波加热的基本原理及影响因素,研究了微波法制备缠绕着丙烯酸交联物的吸水性无纺布的生产工艺,讨论了AA浓度、引发剂用量、辐射时间、交联剂用量诸因素对无纺布相对吸水率的影响。通过正交实验得出最佳工艺条件及配方:微波功率485W,微波辐射时间30s,AA浓度35％,引发剂与单体摩尔比为0.05,交联剂用量为0.3％。与常规法相比,微波加热法优于常规加热法。

土工布透水性测定仪校准方法与影响分析

介绍了土工布透水性测定仪的工作原理和用途,建立了土工布透水性测定仪校准结果的测量模型,分析了各不确定度分量主要来源,结合测量实例具体数据,对其合成不确定度进行分析评定,对各不确定度分量进行计算并得出合成不确定度和扩展不确定度,最终可得出该项目的校准测量能力,为纺织行业提供的技术支撑。

间接蒸发冷却器高效换热材料亲水和布水研究

研究间接蒸发冷却器高效换热材料的亲水性与布水均匀性。采用测试接触角、喷雾布水、喷淋布水等方法,分别对聚丙烯高分子材料、金属铝箔材料、植物纤维聚合物材料的亲水性和布水性进行对比分析。结果表明:材料亲水性较优顺序依次为植物纤维聚合物材料、金属铝箔材料、聚丙烯高分子材料。喷嘴布水均匀应该控制的喷雾布水时间:聚丙烯高分子材料,02^(#)、03^(#)喷嘴布水时间120 s~300 s,05^(#)喷嘴布水时间30 s~120 s;金属铝箔材料,02^(#)喷嘴布水时间120 s~300 s,03^(#)、05^(#)喷嘴布水时间30 s~120 s;植物纤维聚合物材料,02^(#)喷嘴布水时间120 s~300 s,03^(#)喷嘴布水时间30 s~120 s。认为:间接蒸发冷却器高效换热材料宜采用亲水性较好的植物纤维聚合物材料和03^(#)喷嘴,喷雾布水时间30 s~120 s;采用喷淋布水时,适当增加喷水量,可使布水更加均匀。

闭式旋转型雨淋喷头的试验研究

介绍闭式旋转型雨淋喷头的结构和工作原理。通过动态热性能试验验证闭式旋转型雨淋喷头玻璃球热反应灵敏度,进行了下垂安装方式两个高度的布水性能试验,通过木垛火灭火试验和不同工作压力的转速试验检验其灭火控制性能,并在0.2 MPa的工作压力下试验连续喷水性能。试验结果表明:闭式旋转型雨淋喷头结构设计利于热传递,具有良好的动态热性能和布水均匀性,且达到轻危险级洒水密度要求,工作稳定可靠。

Hydrological Characteristics of the Rongbuk Glacier Catchment in Mt.Qomolangma Region in the Central Himalayas,China

From 8 April to 11 October in 2005, hydrological observation of the Rongbuk Glacier catchment was carried out in the Mr. Qomolangma （Everest） region in the central Himalayas, China. The results demonstrated that due to its large area with glacier lakes at the tongue of the Rongbuk Glacier, a large amount of stream flow was found at night, which indicates the strong storage characteristic of the Rongbuk Glacier catchment. There was a time lag ranging from 8 to 14 hours between daily discharge peaks and maximum melting （maximum temperature）. As melting went on the time lag got shorter. A high correlation was found between the hydrological process and daily temperature during the ablation period. The runoff from April to October was about 80% of the total in the observation period. Compared with the discharge data in 1959, the runoff in 2005 was much more, and the runoff in June, July and August increased by 69%, 35% and 14%, respectively. The rising of temperature is a major factor causing the increase in runoff. The discharges from precipitation and snow and ice melting are separated. The discharge induced by precipitation accounts for about 20% of the total runoff, while snow and ice melting for about 80%.

Influence of Filter Cloth on the Cathode on the Electroosmotic Dewatering of Activated Sludge

The mechanical dewatering of activated sludge is troublesome due to its high compressibility of solids. The dewatering can be enhanced dramatically by the use of electroosmosis,in which an electric field is applied to the sludge cake.In this study,the influence of filter cloth on the cathode on the dewatering of activated sludge was investigated.It was found that thicker filter cloth led to lower water removal from the sludge cake,so a stainless steel cathode net with small pore size instead of filter cloth was applied,which improves the dewatering efficiency and reduces the electric power consumption.Moreover,water absorbent materials were helpful to remove the water from the sludge cake.For the electroosmotic dewatering at 7 kPa and 24 V·cm-1,the water content in the sludge cake decreased to 60%(by mass) with the average 0.075 kW·h·kg-1of water removed by using the cathode net.

Drainage performance and capillary rise restraint effect of wicking geotextile

Wicking geotextile(WG)is considered as a possible countermeasure to reduce water content in unsaturated soil.In this research,rainfall tests were carried out to verify the drainage performance of WG.And capillary rise tests were conducted to study the effect of WG on the prevention of capillary rise.Test results indicated that WG with good drainage performance could drain gravitational and capillary water out of kaolinite soil.For kaolinite soil column with water content of 12%and compaction degree of 90%,the whole process of capillary rise in soil column with a layer of WG was a typical two-stage mode,and the maximum capillary height was about 380 mm,which provided that the WG could work as a barrier to prevent capillary rise effectively.In addition,the total vertical influential regions of WG in kaolinite soil above and below the WG layer were 400 and 100 mm,respectively.

Spatial Trend of Foot and Mouth Disease Virus (FMDV) Serotypes in Cattle and Buffaloes, Pakistan

The present study describes the frequency of Foot and Mouth Disease （FMD） virus serotypes （O, A and Asia-l） in major regions （all provinces） of Pakistan using Indirect Sandwich ELISA. Also, spatial distribution of various FMD serotypes and their comparison is discussed. A total of 590 samples （Epithelial tissue） have been analyzed during a period of five years （2005-2009）. Out of 590 samples, 180 were found positive, giving an overall confirmation of FMDV about 33.2 %. Of the prevalent serotypes, FMDV ＇O＇ serotype caused most outbreaks （20.7 %）, followed by serotype A （6.6 %） and serotype Asia-1 （4.6 %） while there was no positive case of type ＇C＇. The study clearly showed that the disease was more frequent in the agro-climatic zones than in hilly areas. Based on the data of 590 samples （〉50 outbreaks）, the overall prevalence of FMDV in cattle and buffaloes in Pakistan was 33.2 %, while in cattle alone, it was 37.1%, higher than in buffalo （28.7 %）. There were eight cases of mixed serotypes infection, indicating the presence of endemic state of disease. Another significant feature was the change over time. In phase-I （2005-2007）, there was an overall prevalence of 29.4 %, while the occurrence of the serotype O, A and Asia-1 was 20.4 %, 2.9 % and 4.7 %, respectively. During phase-II （2008-2009）, the overall prevalence was 59.21%, while those of serotype O, A and Asia-1 were 22.4 %, 31.6 % and 4.0 %, respectively. This clearly indicated a shift from serotype O to A, which may help to explain the occurrence of more severe outbreaks, despite vaccination.

Influences of strain softening and seepage on elastic and plastic solutions of circular openings in nonlinear rock masses

Considering the influence of strain softening, the solutions of stress, displacement, plastic softening region radius and plastic residual region radius were derived for circular openings in nonlinear rock masses subjected to seepage. The radial stress distribution curve, ground reaction curve, and relation curve between plastic softening region radius and supporting force in three different conditions were drawn respectively. From the comparisons among these results for different conditions, it is found that when the supporting force is the same, the displacement of tunnel wall considering both seepage and strain softening is 85.71% greater than that only considering seepage. The increase values of radial displacement at 0.95 m and plastic softening region radius at 6.6 m show that the seepage and strain softening have the most unfavorable effects on circular opening stability in strain softening rock masses.

Future projection of East China Sea temperature by dynamic downscaling of the IPCC_AR4 CCSM3 model result

Future temperature distributions of the marginal Chinese seas are studied by dynamic downscaling of global CCSM3 IPCC_AR4 scenario runs. Different forcing fields from 2080-2099 Special Report on Emissions Scenarios （SRES） B1, A1, and A2 to 1980-1999 20C3M are averaged and superimposed on CORE2 and SODA2.2.4 data to force high-resolution regional future simulations using the Regional Ocean Modeling System （ROMS）. Volume transport increments in downscaling simulation support the CCSM3 result that with a weakening subtropical gyre circulation, the Kuroshio Current in the East China Sea （ECS） is possibly strengthened under the global wanning scheme. This mostly relates to local wind change, whereby the summer monsoon is strengthened and winter monsoon weakened. Future temperature fluxes and their seasonal variations are larger than in the CCSM3 result. Downscaling 100 years＇ temperature increments are comparable to the CCSM3, with a minimum in B1 scenario of 1.2-2.0~C and a maximum in A2 scenario of 2.5-4.5~C. More detailed temperature distributions are shown in the downscaling simulation. Larger increments are in the Bohai Sea and middle Yellow Sea, and smaller increments near the southeast coast of China, west coast of Korea, and southern ECS. There is a reduction of advective heat north of Taiwan Island and west of Tsushima in summer, and along the southern part of the Yellow Sea warm current in winter. There is enhancement of advective heat in the northern Yellow Sea in winter, related to the delicate temperature increment distribution. At 50 meter depth, the Yellow Sea cold water mass is destroyed. Our simulations suggest that in the formation season of the cold water mass, regional temperature is higher in the future and the water remains at the bottom until next summer. In summer, the mixed layer is deeper, making it much easier for the strengthened surface heat flux to penetrate to the bottom of this water.

Spatial distribution and environmental characterization of sediment-associated metals from middle-downstream of Xiangjiang River,southern China

The contamination and environmental risk assessment of the toxic elements in sediments from the middle-downstream (Zhuzhou-Changsha section) of the Xiangjiang River in Hunan Province of China were studied. The results show that As, Cd, Pb and Zn are major contaminants in sediments, and average concentrations of these elements significantly exceed both the Control Standards for Pollutants in Sludge of China (GB4284-84) for agricultural use in acidic soils and the effect range median (ERM) values. The average concentrations of As, Cd and Pb in the river water slightly exceed the limit of Surface Water Environment Quality Standard (GB3838-2002). The concentrations of As and Cr in depth profiles extensively change, but slight changes are observed in Pb and Zn. Cd and Zn in most sediment samples can easily enter the food-chain and bring possible ecotoxicological risk to organisms living in sediments according to the risk assessment code.

Resistivity in Formation and Decomposition of Natural Gas Hydrate in Porous Medium

A new one-dimensional system for resistivity measurement for natural gas hydrate(NGH)exploitation is designed,which is used to study the formation and decomposition processes of NGH.The experimental results verify the feasibility of the measurement method,especially in monitoring the nucleation and growth of the NGH. Isovolumetric formation experiment of NGH is performed at 2°C and 7.8 MPa.Before the NGH formation,the initial resistivity is measured to be 4-7Ω·m,which declines to the minimum value of 2-3Ω·m when NGH begins to nucleate after the pressure is reduced to 3.3 MPa.As the NGH grows,the resistivity increases to a great extent,and finally it keeps at 11-13Ω·m,indicating the completion of the formation process.The NGH decomposition experiment is then performed.When the outlet pressure decreases,NGH begins to decompose,accordingly,the resistivity declines gradually,and is at 5-9Ω·m when the decomposition process ends,which is slightly higher than the resistivity value before the formation of NGH.The occurrence and distribution uniformity of NGH are determined by the distribution and magnitude of the resistivity measured on an one-dimensional sand-packed model.This study tackles the accurate estimation for the distribution of NGH in porous medium,and provides an experimental basis for further study on NGH exploitation in the future.

用于PP非织造织物的纤维亲水整理剂

介绍了英国Uniqema公司研制的CirrasolPP 842和CirrasolPP 82 2纤维亲水整理剂。这是能使织物快速、反复传递水分和其他液体的高效芯吸剂 ,可用于尿布、妇女卫生用品等包覆材料的整理。

Spatial Distribution and Seasonal Variations of Heavy Metal Contamination in Surface Waters of Liaohe River, Northeast China

Heavy metal pollutants are a worldwide concern due to slow decomposition, biocondensation, and negative effects on human health. We investigated seasonal and spatial variations of the five heavy metals and evaluated their health risk in the Liaohe River, Northeast China. A total of 324 surface water samples collected from 2009 to 2010 were analyzed. Levels(high to low) of heavy metals in the Liaohe River were: zinc(Zn) > chromium(Cr) > copper(Cu) > cadmium(Cd) > mercury(Hg). Spatial and seasonal changes impacting concentrations of Cu and Zn were significant, but not significant for Cr, Cd and Hg. The highest concentrations of heavy metals were: Hg at Liuheqiao, Cu at Fudedian, Zn at Tongjiangkou, Cr at Mahushan, and Cd at Shenglitang. The highest concentrations of Hg and Cr were found in the wet period, Cu and Cd in the level period, and Zn in the dry period. The surface water of a tributary was an important accumulation site for heavy metals. Health risks from carcinogens and non-carcinogens increased from upstream to downstream in the mainstream of the Liaohe River. The total health risk for one person in the Liaohe River exceeded acceptable levels. The total health risk was the greatest during the wet period and least in the dry period. Among the five heavy metals in the Liaohe River, Cr posed the greatest single health risk.