管道内瓦斯爆炸传播的试验研究

运用大型试验管道对瓦斯爆炸传播规律进行试验研究,并对瓦斯爆炸压力峰值、火焰速度和呈现时间进行分析,得出:在不出现爆轰的前提下,爆源点附近的压力峰值是全管道的最大值;爆炸压力峰值在沿管道的传播过程中从爆源点附近是先增大后减小,然后再逐渐增大且压力峰值最早呈现在出口附近;火焰传播速度随着传播距离的增大而逐渐增大且在爆炸初期增大速率更快;瓦斯浓度对爆炸压力峰值、火焰传播速度和呈现时间等都有重要影响。     

淮河干流河南段水质预测模型试验研究

淮河干流在河南省境内总长417 km,随着区域经济的发展和人口的增长,淮河干流水环境质量形势不容乐观。根据水体扩散理论,建立了淮河干流水质预测相关模型,并进行了科学验证。对淮河干流河南段氨氮、化学需氧量衰减系数及富氧和耗氧系数4个项目开展现场试验及科学分析,为水资源保护规划中计算水体纳污能力、预测污染物浓度、制定污染物控制方案等提供坚实基础和技术支持。     

Impairment due to alcohol,tetrahydrocannabinol, and benzodiazepines in impaired drivers compared to experimental studies

Objective: In some countries, per se laws for other drugs than alcohol are used to judge drunk and drugged drivers. These blood concentration limits are often derived from experimental studies on traffic relevant behavior of healthy volunteers. Knowledge about how results from experimental studies could be transferred to a real-life setting is missing. The aim of this study was to compare impairment seen in experimental studies to the impairment seen at equivalent concentrations in apprehended drunk and drugged drivers.

Methods: Results from previously performed meta-analyses of experimental studies regarding impairment from alcohol, tetrahydrocannabinol (THC), and benzodiazepines were compared to impairment in apprehended drunk and drugged drivers as judged by a clinical test of impairment. Both experimental studies and real-life cases were divided into 4 groups according to increasing blood drug concentration intervals. The percentage of impaired test results in experimental studies was compared to the percentage of impaired subjects among drivers within the same blood drug concentration window.

Results: For ethanol, the percentage of impaired drivers (n = 1,223) increased from 59% in the lowest drug concentration group to 95% in the highest drug concentration group, compared to 7 and 72% in the respective groups in experimental studies. For THC, the percentage of impaired drivers (n = 950) increased from 42 to 58%, the corresponding numbers being 11 and 42% for experimental studies. For benzodiazepines, the percentage of impaired drivers (n = 245) increased from 46 to 76%, the corresponding numbers being 16 and 60% for experimental studies. The increased odds ratio for impairment between 2 concentration groups was comparable for experimental studies and impaired drivers.

Conclusions: Fewer test results indicated impairment in experimental studies compared to impaired drivers in real life when influenced by similar blood concentrations of either ethanol, THC, or benzodiazepines. In addition, a comparable relationship between drug concentration and impairment was seen for both experimental studies and real-life cases.

We believe that the present study strengthens the background for using experimental studies to establish fixed concentration limits for drunk and drugged drivers, but experimental studies in an impaired driver population could further expand our knowledge.     

两种实验设计研究DES和EV对MCF-7细胞增殖的联合作用

研究了己烯雌酚(DES)和戊酸雌二醇(EV)对MCF-7细胞增殖的单一毒性和等浓度配比下的联合毒性作用,用相加指数法进行了联合毒性作用类型的判断,同时进行了联合毒性作用的3×3析因实验设计研究结果作为对比.结果表明,EV的24、48和72 h对MCF-7细胞增殖率的EC50值分别为6.02、0.40和0.33 nmol·L-1,DES的24、48和72 h的EC50值分别为5.90、6.98和2.90 nmol·L-1,等浓度配比下其联合毒性的EC50值分别为2.33、0.71和0.39 nmol·L-1,用相加指数判断其联合作用类型,在24 h显示为协同作用,其它两个时间段显示为拮抗效应,但从数值上可以发现协同和拮抗效应均不强,接近相加的联合效应类型.析因实验结果显示24、48和72 h这3个染毒时间段均显示了相加作用类型.析因实验与等浓度配比下获得的联合毒作用类型基本一致,但析因实验设计更为简捷方便,同时避免了由于计算EC50值产生的偏差对联合效应类型的影响.     

基于实验模态研究的新型节流降压喷注复合消声器

针对节流降压小孔喷注复合消声器进行实验模态研究。由采集力的激励信号和响应信号,对其进行传递函数分析,寻找消声器所有的模态频率和模态振型。这些频率避开了噪声的峰值频率,消声器不易发生共振,抑制噪声辐射,延长消声器的使用寿命。它对寻找消声器的实际特性,设计性能优良的新型消声器提供可靠的参考依据。     

金在热液中的地球化学性质实验研究

通过近百次实验研究表明，金在水热条件下的地球化学行为具有以下几个特点：金在氧化条件下溶解，还原条件下沉淀；金在高温下溶解，低温下沉淀；金在碱性或酸性溶液中溶解，在中性溶液中沉淀；金在低压下溶解，在高压下沉淀；随着fs八的增加，金的溶解度随之增加；金可以[An（HS）4]、[Au（HS）2]-、[Au（Cl4）]、[Au（Cl2）]-等络合物形式存在于热液中；在热液中金普遍以An3＋的络合物形式存在，Aul＋的络合物形式次之，随着温度的升高，热液中Au1＋的含量明显增加。     

Surface reaction of Bacillus cereus biomass and its biosorption for lead and copper ions

In this study, the surface chemical functional groups of Bacillus cereus biomass were identified by Fourier transform infrared （FTIR） analytical technique. It had been shown that the B. cereus cells mainly contained carboxyl, hydroxyl, phosphate, amino and amide functional groups. The potentiometric titration was conducted to explain the surface acid-base properties of aqueous B. cereus biomass. The computer program FITEQL 4.0 was used to perform the model calculations. The optimization results indicated that three sitesthree pKas model, which assumed the cell surface to have three distinct types of surface organic functional groups based on the IR analysis results, simulated the experimental results very well. Moreover, batch adsorption experiments were performed to investigate biosorption behavior of Cu（Ⅱ） and Pb（Ⅱ） ions onto the biomass. Obviously, the adsorption equilibrium data for the two ions were reasonably described by typical Langmuir isotherm.     

Oxidation of As(Ⅲ) by potassium permanganate

The oxidation of As(Ⅲ) with potassium permanganate was studied under conditions including pH, initial As(Ⅲ) concentration and dosage of Mn(Ⅶ). The results have shown that potassium permanganate was an effective agent for oxidizing of As(Ⅲ) in a wide pH range. The pH value of tested water was not a significant factor affecting the oxidation of As(Ⅲ) by Mn(Ⅶ). Although theoretical redox analyses suggest that Mn(Ⅶ) should have better performance in oxidization of As(Ⅲ) within lower pH ranges, the experimental results show that the oxidation efficiencies of As(Ⅲ) under basic and acidic conditions were similar, which may be due to the adsorption of As(Ⅲ) on the Mn(OH)2 and MnO2 resulting from the oxidation of As(Ⅲ).     

中外垃圾土体渗透系数试验对比分析

从试验数据、试验方法 2个方面总结归纳了关于现有垃圾填埋场渗透系数的国内外试验,并且通过对比国内外渗透系数的一系列试验成果,分析了国内外渗透系数试验在基础数据、试验方法多样性方面的优劣。以此为基点,对未来国内岩土工程发展方向提出了建议。