防弹衣舒适性能改善设计

本文通过对防弹衣的改进研究,探讨了利用经编间隔织物对防弹装备舒适性提高的可行性。用经编间隔织物代替传统防弹衣里料（平纹机织布）,并制成成衣。通过红外热成像仪分别测试以经编间隔织物为里料的防弹衣的热湿传导性、透气散热性来探讨经编间隔织物对防弹衣的舒适性能的影响。实验结果表明：在相同测试条件下,以经编间隔织物为里料的防弹衣的热湿传导性能良好,透气散热性优于传统防弹衣1℃左右。因此经编间隔织物对提高防弹衣的舒适性能具有推动作用。本课题的研究意义在于为警用防弹衣的舒适性能提供理论参考,为警察或军队的作战能力提高做出更大的贡献。     

Influence of laneway support spacing on methane/air explosion shock wave

A laneway support system provides an available way to solve problems related to ground movements in underground coal mines, but also poses another potential hazard. Once a methane/air explosion occurs in a laneway, inappropriate design parameters of the support system, especially the support spacing, likely have a negative influence on explosion disaster effects. The commercial software package AutoReaGas, a computational fluid dynamics code suitable for gas explosions, was used to carry out the numerical investigation for the methane/air explosion and blast process in a straight laneway with different support spacing. The validity of the numerical method was verified by the methane/air explosion experiment in a steel tube. Laneway supports can promote the development of turbulence and explosion, and also inhibit the propagation of flame and shock wave. For the design parameters in actual laneway projects, the fluid dynamic drag due to the laneway support plays a predominant role in a methane/air explosion. There is an uneven distribution of the peak overpressure on the same cross section in the laneway, and the largest overpressure is near the laneway walls. Different support spacing can cause obvious differences for the distributions of the shock wave overpressure and impulse. Under comparable conditions, the greater destructive effects of explosion shock wave are seen for the laneway support system with larger spacing. The results presented in this work provide a theoretical basis for the optimized design of the support system in coal laneways and the related safety assessments.     

Cu Ni As Cr对萝卜出苗的影响

利用盆栽试验研究Ｃｕ、Ｎｉ、Ａｓ、Ｃｒ４个元素不同浓度对萝卜出苗的影响．结果表明，土壤含Ｃｕ５０ｍｇ／ｋｇ以上时，随着含Ｃｕ量的增加，出苗数随之减少．在酸性土壤上发生Ｃｕ和Ｎｉ危害时，可用提高土壤ｐＨ至中性的办法来消除．在中性土壤上，含Ｎｉ５０ｍｇ／ｋｇ以上对萝卜出苗有害．Ｃｕ、Ｎｉ复合污染比单一元素污染的危害大，且毒性Ｎｉ＞Ｃｕ．土壤Ｃｒ、Ａｓ含量越大，对萝卜出苗的危害也越大，并且毒性Ｃｒ（６＋）＞Ｃｒ（３＋）．     

DEHP在土壤和白菜中的残留及毒性分析

用聚氯乙烯（ＰＶＣ）塑膜覆盖白菜地，收获期土壤和白菜植株中ＤＥＨＰ的残留量分别为２．７３ｍｇ．ｋｇ＾－１和３．０５ｍｇ．ｋｇ＾－１。借鉴国外的评价指标，对人体食用白菜后的潜在危害进行了分析认为，人每天摄入干白菜中ＤＥＨＰ的量〈０．０５ｍｇ．ｋｇ＾－１，远低于人每天可接受ＤＥＨＰ的安全摄入量１ｍｇ．ｋｇ＾－１。     

Semi-volatile species in PM2.5: comparison of integrated and continuous samplers for PM2.5 research or monitoring

Fine particles in urban atmospheres contain substantial quantities of semi-volatile material [e.g., NH4NO3 and semi-volatile organic compounds (SVOCs)] that are lost from particles during collection on a filter. Several diffusion denuder samplers have been developed for the determination of both NO3- and organic semi-volatile fine particulate components. The combination of technology used in the BOSS diffusion denuder sampler and the Harvard particle concentrator has resulted in the Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS) for the 24-hr (or less) integrated collection of PM2.5, including NH4NO3 and semi-volatile organic material. Modification of the BOSS sampler allows for the weekly determination of these same species. Combination of BOSS denuder and tapered element oscillating microbalance (TEOM) monitor technology has resulted in the real-time ambient mass sampler (RAMS) for the continuous measurement of PM2.5, including the semi-volatile components. Comparison of the results obtained with the BOSS and with each of the newly developed modifications of the BOSS indicates that the modified versions can be used for the continuous, daily, or weekly monitoring of PM2.5, including semi-volatile species, as appropriate to the design of each sampler.     

微生物制剂在城市湖泊水体生物修复中的作用

利用微生物对富营养化的城市湖泊水体进行生物修复，使水中的污染物降解成H2O、CO2或转化成无害物质。研究表明，该微生物制剂对去除水体中的有机物、叶绿素a、氨氮和提高溶解氧等均有显著效果。为节省运输费用及延长菌液保存期，本试验用惰性粒子流化床对生物制剂进行干燥，固体菌粉末不失活性。     

Solutions and verification of a scale-dependent dispersion model

In this paper, analytical solutions are derived for a one-dimensional scale-dependent dispersion model (SDM), considering linear equilibrium sorption and first-order degradation for continuous and pulse contaminant sources, with a constant input concentration in a semi-infinite uniform porous medium. In the SDM model, dispersivity alpha(x) is replaced with a constant epsilon multiplied by the transport distance x. The solution for a pulse source is verified experimentally in the analysis of tritium data obtained from an 8-m-long homogenous pea-gravel column with multiple sampling locations, and the results are compared with those analysed by a commonly used solution of a constant dispersion model (CDM). The SDM predicts concentrations satisfactorily at all sampling locations, while the CDM fits the experimental data well for only one location. Both models are then calibrated for each individual concentration breakthrough curve, using local values for either epsilon in the SDM or alpha(x) in the CDM. Both models give equally good fits for appropriate choices of individual epsilon and alpha(x) values, and both indicate a linear increase in alpha(x) with distance. The epsilon values tend to change little as x increases and are expected to approach a constant at relatively large distances downstream. Hence, predictions from the SDM should become more accurate as x increases.     

用于干式脱污的CaO蒸汽活化实验研究

利用小型活化转炉实验台对以CaO为主要成分的钙基脱污剂在300～650℃的温度范围内进行蒸汽活化处理,结合X射线衍射和压汞仪的分析结果,初步探讨了蒸汽活化的机理.研究表明,蒸汽活化温度在600℃以上时,脱污剂孔隙结构有显著的改善,比孔容积和比表面积有着显著的增加,微孔（＜100nm）的数量大量增加,而低温下蒸汽活化的效果不是十分明显;研究还发现高温下延长活化时间有利于改善脱污剂的孔隙结构.     

Effect of pore-water velocity on chemical nonequilibrium transport of Cd,Zn, and Pb in alluvial gravel columns

This paper investigates the effects of pore-water velocity on chemical nonequilibrium during transport of Cd, Zn, and Pb through alluvial gravel columns. Three pore-water velocities ranging from 3 to 60 m/day were applied to triplicate columns for each metal. Model results for the symmetric breakthrough curves (BTCs) of tritium (3H2O) data suggest that physical nonequilibrium components were absent in the uniformly packed columns used in these studies. As a result, values of pore-water velocity and dispersion coefficient were estimated from fitting 3H2O BTCs to an equilibrium model. The BTCs of metals display long tailing, indicating presence of chemical nonequilibrium in the system, which was further supported by the decreased metal concentrations during flow interruption. The BTCs of the metals were analysed using a two-site model, and transport parameters were derived using the CXTFIT curve-fitting program. The model results indicate that the partitioning coefficient (beta), forward rate (k1), and backward rate (k2) are positively correlated with pore-water velocity (V); while the retardation factor (R), mass transfer coefficient ((omega), and ratio of k1/k2 are inversely correlated with V. There is no apparent relationship between the fraction of exchange sites at equilibrium (f) and V. The influence of Von k2 is much greater than on R, beta, omega, and k1. A one-order-of-magnitude change in V would cause a two-order-of-magnitude change in k2 while resulting in only a one order-of-magnitude change in R, beta, omega, and k1. The forward rates for the metals are found to be two to three orders-of-magnitude greater than the corresponding backward rate. However, the difference between the two rates reduces with increasing pore-water velocity. Model results also suggest that Cd and Zn behave similarly, while Pb is much more strongly sorbed. At input concentrations of about 4 mg/l and pore-water velocities of 3-60 m/day in the groundwater within alluvial gravel, this study suggests retardation factors of 26-289 for Cd, 24-255 for Zn, and 322-6377 for Pb.