SPE-RRLC-MS/MS法测定制药废水中青霉素G

建立了利用固相萃取-高分离度快速液相色谱-串联质谱(SPE-RRLC-MS/MS)测定制药废水中青霉素G残留的方法。水样以30%硫酸锌+20%亚铁氰化钾作为沉淀剂沉淀蛋白质后,上清液采用Oasis HLB固相萃取柱富集和净化,以0.01 mol/L乙酸铵溶液(加0.1%甲酸)+乙腈作为流动相进行等度洗脱,经Agilent Plus C18柱分离后,在串联质谱ESI(+)源下进行MRM检测。该方法的青霉素G检出限(S/N=3)为0.02μg/L,目标物在0.0020～1.0 mg/L范围内线性关系良好,线性相关系数为0.9997。在0.20,1.0,2.0μg/L添加水平平均回收率为74.6%～101.4%,相对标准偏差为4.49%～8.17%。该方法灵敏度高、重现性好、定性定量准确,可满足制药废水中青霉素G残留检测的要求。     

The quandary of local people—Park relations in Nepal's Royal Chitwan National Park

This paper analyzes five major causes of park-people conflicts that have occurred in Nepal's Royal Chitwan National Park. The causes include illegal transactions of forest products from the park, livestock grazing in the park, illegal hunting and fishing, crop damage, and threats to human and animal life caused by wild animals from the park. The conflicts indicate a reciprocal relationship between the park and local people. They reflect the attitudes of local people and representatives of the park authority whose priorities and objectives largely diverge. The results show that people settled adjacent to the park are heavily dependent on its resources. Even in places where some, albeit few alternative sources exist, local people continue to trespass the park boundary as these sources are inadequate to ensure the fulfillment of local people's resource needs. Illegal transactions of resources continue throughout the year; however, they are less intense during summer due to flooding caused by the Rapti River, which forms the park boundary towards the northern section where this study is conducted. The frequency of local people's visits to the park is mainly determined by their age, distance between homesteads and park, and volume of crop loss caused by wild animals. Crop damage is the function of size of landholding, distance, and frequency of crop raid. Local people claim that they have no intention of letting their livestock graze in the park; however, the dense vegetation of the park attracts livestock grazing on riverbanks just outside the open park boundary. Many head of livestock are killed by carnivores of the park. Human casualties are mainly caused by sloth bear (Melursus ursinus), tiger (Panthera tigris), wild pig (Sug scrofa), and rhinoceros (Rhinoceros unicornis). There had been some earlier attempts to reconcile the conflicts by offering local people different kinds of compensations; however, these were unsuccessful measures. An integrated approach is essential if efforts to resolve the park-people conflicts are to succeed. The government is in the process of launching a project that aims to resolve the inherent problems with such an approach. Suggestions are made to incorporate some key elements, such as maintaining effective communication between various parties and the potential for wildlife conservation among local people.     

TECHNICAL CLARITY IN INTER-AGENCY NEGOTIATIONS: LESSONS FROM FOUR HYDROPOWER PROJECTS1

ABSTRACT: We investigated the effect of technical clarity on success in multi-party negotiations in the Federal Energy Regulatory Commission (FERC) licensing process. Technical clarity is the shared understanding of dimensions such as the geographic extent of the project, range of flows to be considered, important species and life stages, and variety of water uses considered. The results of four hydropower licensing consultations are reported. Key participants were interviewed to ascertain the level of technical clarity present during the consultations and the degree to which the consultations were successful. Technical clarity appears to be a prerequisite for successful outcomes. Factors that enhance technical clarity include simple project design, new rather than existing projects, precise definition of issues, a sense of urgency to reach agreement, a sense of fairness among participants, and consistency in participation. Negotiators should not neglect the critical pre-negotiation steps of defining technical issues and determining appropriate studies, deciding how to interpret studies, and agreeing on responses to study results.     

局域网内ARP协议攻击及解决办法

地址解析协议(ARP,Address Resolution Protocol)是用于关联某个3层(网络层)地址(如IP地址)和某个两层(数据链路层)地址(MAC地址)。由于ARP协议的自身的缺陷,使得ARP协议在使用的过程中存在着盗用IP地址和ARP欺骗等严重的安全问题。笔者在对ARP协议简要介绍的基础上,主要分析了利用ARP协议漏洞进行网络攻击的原理和攻击的常见方式,并提出相关的ARP攻击的解决办法。     

卫星遥感技术在本溪典型区域的应用

以本溪典型区域为研究区,以高分辨率卫星数据为主要信息源,利用不同波段的组合图像,借助eCognition软件,对地表地物光谱特征和空间特征进行分析,建立卫星遥感分析成果信息库。基于不同时相分类结果的变化检测,以及对研究区水体污染、矿区复垦、耕地变化、林地变化等的分析,定量分析了研究区生态环境的动态变化。此项研究工作为研究区的生态环境规划、建设和管理,特别是对土地利用的管理工作提供了有用的资料。     

200MW燃煤机组SCR脱硝改造关键技术问题解析

目前,国内200 MW机组SCR脱硝改造尚无样板工程及改造先例。200 MW机组由于其独特地设计,同300 MW以上等级机组相比,脱硝改造的技术方式与改造内容均有较大的差异。文章从国内200 MW机组脱硝改造实际情况出发,从设计参数选取、还原剂选择、SCR反应器布置方式、低氮燃烧器改造、空预器改造及引风机改造、厂用变压器系统改造等关键问题进行了技术分析并提出可行建议,为同等级机组脱硝改造工作提供方法与经验。     

机场大气污染物高时间分辨率排放清单计算方法研究

通过研究机场大气污染物排放特征,结合我国相关排放政策及规范,以排放因子法为主要方法,设计了可建立机场高时间分辨率大气污染物排放清单的计算方法,以期为机场大气污染物排放实时监管提供研究基础。该方法针对飞机发动机和地面保障设备(GSE),实现了颗粒物、二氧化硫、氮氧化物等大气污染物和温室气体的半小时级别排放量计算。通过收集整理北京首都国际机场日航班计划与GSE运作情况实际数据,计算并建立了高时间分辨率的排放清单,验证了计算方法的可行性。随后,从活动水平误差和排放因子适用性两方面,对清单进行了不确定性分析,并通过计算结果对机场排放特征进行了分析,提出了减排建议。     

现代受体模式评述

传统的数学受体模式可概括地分为两大类,即化学质量平衡法(CMB)和多元技术(MVT),CMB由于要求已知所求源的成分谱。从而在应用中受到限制。MVT以因子模式为中心,由于因子模式的本征向量解法求解不唯一或称误差太大,使得MVT给人一种人造数据的印象。近年来,元素示踪体系将受体模式的应用范围从城市尺度扩展到区域尺度,由于该体系经验性太强,未能得到广泛的应用。本文针对现代受体模式中存在的一些关键性问题作了系统的评述。      

廊坊市夏季大气气溶胶消光特性及其来源

通过对廊坊市2016年5~9月的空气污染指标进行连续观测,分析了PM_2.5污染特征、消光特性,并进行来源解析及潜在污染区域分析.观测期间PM_2.5浓度为（43.82±28.68）μg/m,PM_2.5中SO₄^2-,NO₃^-,NH₄⁺,OC和EC分别占PM_2.5总质量的24.74%,22.98%,20.54%,8.79%和5.50%,各组分随着PM_2.5浓度增加而增加;气溶胶散射系数（Bsp）和吸收系数（Bap）分别为（294.54±257.35）,（16.05±9.14）Mm^-1,粗粒子（CM）对消光系数的贡献为11.12%,细颗粒子PM_2.5在大气消光中起主要作用,其中硝酸盐（32.23%）,硫酸盐（27.28%）和OM （20.56%）为最主要消光成分;PM_2.5主要来自工业（14.14%）、机动车（15.15%）、二次无机气溶胶（38.38%）、燃煤（22.22%）及扬尘和生物质燃烧（10.10%）,对消光系数的贡献分别为工业（1.32%）、机动车（17.25%）、二次气溶胶（55.57%）、燃煤（18.56%）,扬尘和生物质燃烧（7.32%）.后轨迹分析表明廊坊市以来自山东、河南的小尺度_,短距离和来自内蒙古东北部、中部的中短距离传输为主,占比接近80%,污染源的潜在分布区域主要是山东东北部、河南东部、山西东部、辽宁西南等地.