基于本质安全的供应链风险识别方法研究

由于集成供应链的构成较为复杂,来自供应链内部、外部的风险因素众多,单凭建立附加的防护系统并不能从根本上解决集成供应链的风险损失问题。因而需要从本质安全的视角出发,从根源上辨识风险源,及时发现供应链中的薄弱环节,消除因风险隐患及控制风险而造成的损失。SCOR模型可以清晰地将整个供应链的组成结构、操作流程描述出来,以此为基础运用模型的顶层、配置层、元素层和实施层这4个层级对集成供应链风险进行了研究。根据集成供应链主体构成的特点将供应链整体风险划分为5类,分别为需求风险、供应风险、运作过程风险、环境风险以及制度风险。并通过建立供应链风险识别指标体系以有针对性地识别某一企业的供应链风险。     

Incidence of organochlorine pesticides in soils of Shenzhen, China

To determine the incidence of organochlorine pesticides (OCPs) in soil in a rapid urbanization region, soil samples from various land use types in Shenzhen were collected in winter, 2007. The concentration of dichlorodiphenyltrichloroethanes (DDTs) and hexachlorocyclohexanes (HCHs) ranged from non-detected to 149 ng g(-1) and 19 to 88 ng g(-1), respectively. The highest levels of OCPs were observed in soil from traffic and industry areas, reflecting that intensive human disturbance make the soil pollution accumulation more disperse. HCHs and DDTs profiles revealed that the sources were associated mainly with lindane and technical DDTs, respectively, while HCHs in the soil of Shenzhen might originate from both recent and historical sources. The loss of OCPs by soil erosion will enter surface runoff and impose impact on the water environment. Non-dietary exposure estimation indicates that children were the most sensitive group. The average daily exposure to OCPs for males was more serious than for females. Non-dietary exposure to DDTs and HCHs in residential blocks of Shenzhen were far below the acceptable daily intake recommended by the Food and Agriculture Organization/World Health Organization.     

Fate estimation of polycyclic aromatic hydrocarbons in soils in a rapid urbanization region, Shenzhen of China

Our previous study indicated that the current level of polycyclic aromatic hydrocarbons (PAHs) in Shenzhen soil is in the low-end of world soil PAH pollution. In this study, the fate of PAHs in the soil of Shenzhen was investigated. The mass inventories of Σ(27)PAHs and Σ(15)PAHs (defined as the sum of the 27 or 15 PAH compounds sought) in topsoil of Shenzhen were ～204 and ～152 metric tons, respectively. Fate estimation of Σ(15)PAHs shows that air-soil gaseous exchange is the primary environmental process with ～10,076 kg/year diffusing from soil to air. Rain washing (～1131 kg/year from air to soil) is the most important input pathway followed by wet (～17 kg/year) and dry deposition (～8 kg/year) to soils in Shenzhen. The transport of Σ(15)PAHs by soil erosion is a crucial loss process for soil PAHs in Shenzhen (1918 kg/year for water runoff and 657 kg/year for solid runoff from soil). Moreover, degradation is not ignorable at present (95 kg/year). Comparison of inventory and residue (defined as Σ(15)PAHs left in topsoils after all environmental loss processes) suggested that input and loss of high molecular weight PAHs for Shenzhen's soil reached apparent equilibrium. Soil PAH pollution in Shenzhen will stay in a quasi-steady state for a long period and the natural environmental processes can not significantly reduce the pollution.     

Combustion and inorganic bromine emission of waste printed circuit boards in a high temperature furnace

High temperature combustion experiments of waste printed circuit boards (PCBs) were conducted using a lab-scale system featuring a continuously-fed drop tube furnace. Combustion efficiency and the occurrence of inorganic bromine (HBr and Br₂) were systematically studied by monitoring the main combustion products continuously. The influence of furnace temperature (T) was studied from 800 to 1400 °C, the excess air factor (EAF) was varied from 1.2 to 1.9 and the residence time in the high temperature zone (RT_HT) was set at 0.25, 0.5, or 0.75 s.Combustion efficiency depends on temperature, EAF and RT_HT; temperature has the most significant effect. Conversion of organic bromine from flame retardants into HBr and Br₂ depends on temperature and EAF. Temperature has crucial influence over the ratio of HBr to Br₂, whereas oxygen partial pressure plays a minor role. The two forms of inorganic bromine seem substantially to reach thermodynamic equilibrium within 0.25 s. High temperature is required to improve the combustion performance: at 1200 °C or higher, an EAF of 1.3 or more, and a RT_HT exceeding 0.75 s, combustion is quite complete, the CO concentration in flue gas and remained carbon in ash are sufficiently low, and organobrominated compounds are successfully decomposed (more than 99.9%).According to these results, incineration of waste PCBs without preliminary separation and without additives would perform very well under certain conditions; the potential precursors for brominated dioxins formation could be destroyed efficiently. Increasing temperature could decrease the volume percentage ratio of Br₂/HBr in flue gas greatly.     

温度对小叶海金沙生长的影响

用野外调查测定和室内模拟的方法研究了温度对小叶海金沙生长的影响.结果表明,小叶海金沙疯狂生长群落中的温度比正常生长群落高,且温度与其净光合速率呈极显著正相关,而这两种类型群落内大气相对湿度以及光照差异较小.此外,土壤养分和土壤pH与小叶海金沙的生长速度无明显的关联性.根据研究结果推测:温度可能是小叶海金沙疯狂生长原因之一.     

用“条件”水分平衡法分析湖北省干旱的时空分布规律

从“条件”水分平衡角度和农业生产实际情况出发，提出了一个综合考虑水分盈亏和同期作物需水量的干旱指标，并用此指标分析了湖北省１９６１－１９９０年３０年来的主要干旱类型的时空分布规律及对农业生产的影响。     

pH对铜在黄土中吸持及其形态的影响

用黄土为吸持剂,以石英砂作对照,研究了pH对铜的吸持及形态的影响,并用MINTEQA2模型对铜离子的沉淀形态进行了理论计算.结果表明:无论吸持剂是石英砂还是黄土,随着pH的升高,吸持曲线都分为3区:低pH微吸持区、中pH吸持增长区和高pH强吸持区.含沙量一定,随着铜液初始浓度的增加,吸持量、可交换态含量和碳酸盐结合态含量均增加;铜液初始浓度一定,随着含沙量的增加,吸持量、可交换态含量和碳酸盐结合态含量均减少.MINTEQA2模型计算结果表明,对于不同的吸持剂,铜离子发生沉淀的比例及沉淀的物质组成是不同的;以黄土为吸持剂时,中pH范围内随着含沙量的增加铜离子沉淀的比例减少.     

Factors influencing the contents of metals and As in soils around the watershed of Guanting Reservoir, China

Topsoil samples from 61 sites around the Guanting Reservoir,China,were measured for Cu,Zn,Cr,Ni,Cd,Pb and As concentrations.The mean concentrations of Cu,Zn,Cr,Ni,Cd,Pb and As were 16.8,59.4,37.8,18.3,0.32,20.1 and 8.67 mg/kg dry weight,respectively.Factors that influence the dynamics of these metals in soils around the watersheds of Beijing reservoirs were examined.The influence of atmospheric deposition,land use,soil texture,soil type and soil chemical parameters on metal contents in soils was investigated.Atmospheric deposition,land use and soil texture were the important factors affecting heavy metal residues.Soil type and soil chemical parameters were also involved in heavy metal retention in soils.The data provided in this study are considered crucial for reservoir remediation,especially since the Guanting Reservoir will serve as one of the main drinking water sources for Beijing in the foreseeable future.     

祁连山空中云水资源开发利用效益预测与评估

利用社会效益、经济效益和生态效益3 个方面25 项指标, 建立了空中云水资源开发利用综 合效益的评价体系。同时对祁连山区人工增雨对径流的影响作了预估, 在此基础上, 对祁连山云水 资源开发利用后山前走廊各流域水资源状况及社会经济状况进行了合理的预测。最后, 选用其中 11 项指标, 并运用层次分析法对祁连山空中云水资源开发利用效益进行了评价。结果表明: 祁连山 空中云水资源开发利用对山前走廊的社会、经济、生态等效益均显著增加, 祁连山区通过人工增雨, 降水增加10%时, 河西地区综合效益将提高5.3%, 降水增加20%时, 综合效益提高12.5%。     

矸石基X型分子筛对水中Co2+、Cu2+、Cd2+和Cr3+的去除

以煤矸石为原料,采用碱熔后水热合成法制备X型分子筛并进行XRD、SEM、BET和Zeta电位分析。研究其对水中Co2+、Cu2+、Cd2+和Cr3+4种离子的吸附性能,包括吸附等温线、吸附动力学以及初始金属离子浓度、pH值对吸附性能的影响。所合成的矸石基X型分子筛的BET比表面积为676.02 m2/g,微孔孔容为0.263 cm3/g。吸附实验表明,矸石基X型分子筛能有效去除上述4种离子,同时实现煤矸石的资源化和金属离子的去除。4种离子的平衡吸附量均随初始浓度的增大而增大,相同条件下平衡吸附量的大小顺序为Cd2+>Cr3+>Cu2+>Co2+。准二级动力学模型能很好地描述4种离子的吸附动力行为。Langmuir模型对Co2+、Cu2+和Cd2+吸附的拟合较Freundlich模型高,说明其主要表现为物理吸附过程。4种离子的吸附速率均由液膜扩散和颗粒内扩散共同控制。