Catalytic Activity of Biomorphic α-MoO(3) in the Degradation of Methyl Violet Dye

A network of fibers comprising orthorhombic molybdenum trioxide (α-MoO(3)) crystals were synthesized using paper as template via a biomorphic approach. The template was completely removed by annealing the sample at 600°C for 5?min. Monoclinic MoO(3) was formed and consequently converted into orthorhombic α-MoO(3) after prolonged annealing. Three milligrams of the biomorphic α-MoO(3) could degrade up to 90% of a methyl violet aqueous solution with a concentration of 20?mg/L under normal visible light. The size of the α-MoO(3) grains and the porosity of the biomorphic sample affected catalytic performance.     

硫酸钙晶须对磷的静态吸附

以磷石膏废渣为原料制备硫酸钙晶须,考察了硫酸钙晶须对模拟含磷废水中磷的去除效果,分析了初始废水pH、初始磷质量浓度、硫酸钙晶须加入量对磷吸附效果的影响,研究了硫酸钙晶须对磷的吸附等温线,同时对吸附机理进行了探讨。实验结果表明：硫酸钙晶须在碱性条件下对磷的去除率较酸性条件下高,且初始废水pH为10时去除效果最佳;最佳硫酸钙晶须加入量为0.03 g/mg（以磷计）;在初始废水pH为10、初始磷质量浓度为50 mg/L、硫酸钙晶须加入量为1.5 g/L的条件下,于25 ℃下反应1 h,磷的去除率达到99.16%,上清液TP为0.419 mg/L;与Freundlich模型相比,Langmuir等温吸附模型更适合描述硫酸钙晶须对磷的吸附过程,采用该模型拟合得出25 ℃下磷的饱和吸附量为140.4 mg/g。     

漆酶/香草醛体系生物降解毒死蜱影响因素的研究

研究了漆酶介体体系对有机磷农药毒死蜱生物降解的效果及影响因素.通过对6种介体的试验比较,筛选了合适的介体.在试验条件下,1-羟基苯并三唑(HBT)和2,2’-联氮-二(3-乙基-苯并噻唑-6-磺酸)(ABTS)对漆酶降解毒死蜱存在一定的抑制作用,紫脲酸(VA)和2,6-二甲氧基苯酚(2,6-DMP)对漆酶降解毒死蜱未起促进作用,而天然产物香草醛和愈创木酚可促进漆酶降解毒死蜱,香草醛的促进作用最为明显,选择香草醛作为漆酶介体体系中的介体.研究了漆酶/香草醛体系中,反应时间、漆酶初始酶活、pH、温度、介体投加量及投加方式、毒死蜱初始浓度等因素对毒死蜱生物降解效果的影响.结果表明,控制漆酶初始酶活为0.050 U/mL、pH为5.0、温度30℃,分2次投加香草醛(香草醛与毒死蜱初始值摩尔比分别为40和80)情况下,漆酶/香草醛体系即可在24 h内实现对25 mg/L毒死蜱的有效降解,降解率达98％.     

Tolerance, uptake and removal of nitrobenzene by a newly-found remediation species Mirabilis jalapa L

The growth, photosynthesis rate, and ultrastructure of Mirabilis jalapa L. as a newly-found remediation species under stress of nitrobenzene (NB) and its uptake and removal of NB by the plants were investigated. The results showed that M. jalapa plants could endure contaminated soils by lower than 10.0 mg NB kg⁻¹ because there was no decrease in the total length of the plant roots, the maximum length of the hypocotyle, the length of the first seminal root, the height of the shoots and the dry biomass of the seedlings as well as the photosynthesis rate of the plants compared with those in the control. In particular, the growth of the plants could be significantly (P < 0.01) enhanced by 0.1 mg NB kg⁻¹ under unautoclaved and autoclaved soils. Ultrastructural observations on leaf cells of the plants found that these cells had smooth, clean and continuous cell membranes and cell walls, indicating that there was no obvious damage by NB in comparison with those in the control. Although the absorption of NB in shoots and roots of M. jalapa was weak, plant-promoted biodegradation of NB was considerable and the dominant contribution in the removal of NB from contaminated soils, suggesting the feasibility of M. jalapa applied to phytoremediation of NB contaminated soils.     

Levels of polybrominated diphenyl ethers (PBDEs) in breast milk from Beijing, China

The levels of polybrominated diphenyl ethers (PBDEs) in breast milk from Beijing, China, were studied. The 6 predominant PBDEs congeners (BDE47, BDE99, BDE100, BDE153, BDE154 and BDE183) in 23 pooled breast milk samples from 205 mothers living in Beijing were measured. Mean and median of SigmaPBDEs concentrations in all samples were 1.12ngg(-1) lipid and 1.07ngg(-1) lipid, respectively. The Statistical difference in SigmaPBDEs concentrations was found between urban areas (1.22ngg(-1) lipid, n=14) and rural areas (0.97ngg(-1) lipid n=9). The sum of BDE47 and BDE153 accounted for more than 70% of SigmaPBDEs in most samples. The significant correlation was found between the SigmaPBDEs in pooled samples and average of consumption of food of animal origin in the pools in urban area. However, there was no correlation was found between the SigmaPBDEs in pooled samples and average of consumption of food of animal origin in the pools in rural area of Beijing. The current study showed that the level of PBDEs in breast milk from Beijing was lower than that from South China and some developed countries such as USA and Sweden.     

XP产品在消防报警系统中的应用

广州雷迅自2002年研发出全球第一台19英寸标准机架式10/100M自适应网络防雷器以来,一直致力于解决困扰信息系统电涌保护器发展的问题,如信息系统规格繁多、外形繁多、安装方式繁多等等.广州雷迅研发人员综合了低压配电系统电涌保护器的发展历史,并深入调查了各种信息系统的电涌保护需求,详细分析了信息系统电涌保护器在各行业的应用,创新地推出了“XP随心系列”模块化信息系统电涌保护器,并申请了相应的国家专利.彻底或局部解决困扰信息系统电涌保护器的各种问题,为使用者的选型及安装提供真正的随心DIY,并将信息系统电涌保护器的研发思路推向全新的领域.     

Factors associated with higher levels of injury severity in occupants of motor vehicles that were severely damaged in traffic crashes in Kentucky, 2000-2001

OBJECTIVES: The majority of motor vehicle occupants who were killed or hospitalized in crashes in Kentucky in 2000-2001 occupied vehicles that were severely damaged in the crash. Even so, overall only a small percentage of all severely damaged vehicle occupants were killed or hospitalized. The purpose was to identify occupant, vehicle, crash, and roadway/environmental factors that were associated with increased risk of severe injury in crashes where the occupant's vehicle was severely damaged. METHODS: This study probabilistically linked Kentucky's statewide motor vehicle crash and inpatient hospital discharge data files for 2000 and 2001, and selected cases representing occupants of vehicles that were reported by police as having either "severe" or "very severe" damage. For occupants who were identified through data linkage as having been hospitalized, the Injury Severity Score (ISS) was calculated using ICDMAP-90 software, and the scores were stratified into the following categories: critical (>24), severe (15-24), moderate (9-14), and mild (<9). We then created an outcome variable, injury severity level, with five levels: killed; hospitalized with at least moderate injuries (ISS = critical, severe, or moderate); hospitalized with mild injuries (ISS = mild); injured according to the police report but not hospitalized; and no apparent injury according to the police report. We performed a stepwise, ordinal logistic regression of injury severity, using independent variables identified from the existing crash literature. RESULTS: Occupant risk factors for higher levels of injury severity selected by the regression were age (risk increased with age, other factors being equal), female gender, restraint non-use, ejection from the vehicle, and driver impairment (by alcohol and/or drugs). Crash risk factors included head-on collision, collision with a fixed object, vehicle rollover, and vehicle fire. Roadway/environmental factors were federal- or state-maintained roadway and posted speed limit 89 kph (55 mph) or greater. CONCLUSIONS: Many of the identified risk factors are explicitly or implicitly mentioned in the strategic plans of key organizations involved in highway safety and injury prevention in Kentucky. Our analysis provides additional evidence of their importance, and confirms that their mitigation will reduce injury severity in crashes involving severe vehicle damage. Additionally, older occupants and female occupants showed increased risks of serious injury, but to our knowledge these factors are not currently addressed in any state plans. An opportunity exists to clarify the nature of these risks through further studies, which might lead to the identification of countermeasures specific to these populations.     

中国温室气体减排适宜方案的选择

气候变化是当今世界关注的全球性问题。在总结国际上各主要利益集团的减排方案和对策的基础上,根据国际和国内专家的理解并结合中国国情,首先选出适合中国的经济政策和技术政策;在此基础上,运用层次分析法分析这些对策,确定其可行性和优先顺序,提出适合中国的减排对策方案建议。     

Three-dimensional simulation of reservoir temperature and pollutant transport by the lattice Boltzmann method

Predicting the three-dimensional (3D) transport processes of reservoir temperature and pollutants is essential for water environmental protection and restoration, and introducing the lattice Boltzmann (LB) method into this prediction is necessary because of its simple algorithm, straightforward implementation of boundary conditions, and high computation efficiency. In this paper, a triple-distribution function (TDF) LB model for flow-temperature-concentration coupling simulations is introduced. Some essential techniques for implementing this method in 3D reservoirs are also described, including the treatment of water surface fluctuation, the consideration of surface heat exchange, and the hardware acceleration using the graphics processing unit (GPU). Two cases verified the proposed model, and then, the temporal-spatial variations of flow, temperature, and pollutants in the upper reservoir of a pumped-storage power station during both pumping and generating modes were analyzed to demonstrate its applicability. In the reservoir, the water forms several circulations, the cold water from the inlet flows as an undercurrent firstly, and then spread laterally, and the spreading of pollutants directly relates to the flow velocity. The results of flow, temperature, and concentration fields in different working conditions are consistent with model tests and physical laws, which shows good prospects of the proposed LB model.

     

乌鲁木齐市部分商业及娱乐场所室内氡浓度水平调查研究

氡及其衰变子体会对人体产生辐射损伤。高浓度的氡可以致癌,而其具有无色、无嗅及无味的特性,因此难以察觉。据国内外的最新研究结果表明,氡是仅次于吸烟诱发肺病而死亡的第二大病因。对乌鲁木齐市有代表性的商场超市、酒店、娱乐场所以及宾馆的室内氡浓度进行监测,室内氡浓度平均值23．8Bq／m3,低于国标的400Bq／m3;并估算出对其内工作人员所造成的年有效剂量为0．137mSy,低于世界平均值1．008mSy,对于只作短暂停留的客人来说,所受到的剂量还要低。