Gas/particle partitioning of atmospheric PCDD/Fs in a satellite town in Eastern China

Gas/particle partitioning of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in ambient air was investigated in a satellite town in Eastern China from April 2007 to January 2008 comprehending large temperature variations (from 3 to 34 °C, daily average). Molecular weight, molecular structure and ambient temperatures are the three major factors that govern the gas/particle partitioning of atmospheric PCDD/Fs throughout the year. Generally, good agreements were obtained (except for winter) between measured particulate fractions and theoretical estimates of both the Junge–Pankow adsorption model and Harner Bidleman absorption model using different sets of subcooled liquid vapor pressure and octanol–air partition coefficient (K_oa), respectively. Models utilizing estimates, derived from gas chromatographic retention indices (GC-RIs), are more accurate than that of entropy-based. Moreover, during winter, the K_oa-based model using the GC-RIs approach performs better on lower chlorinated PCDD/Fs than that of -based. Furthermore, possible sources of mismatch between measured and predicted values in winter (3–7 °C) were discussed. Gas adsorption artifact was demonstrated to be of minor importance for the phenomena observed. On the other hand, large deviations of slopes (m_r) and intercepts (b_r) in logK_p vs. plots from theoretical values are observed in the literature data and these are found to be linearly correlated with ambient temperatures (P<0.001) in this study. This indicates that the non-equilibrium partitioning of PCDD/Fs in winter may be significantly influenced by the colder temperatures that may have slowed down the exchange between gaseous and particulate fractions.     

基于B/S+C/S的矿山安全标准化管理信息系统研究

首先介绍了安全标准化实施的关键步骤、技术特点及其在矿山的应用,通过现场调研、安全培训,危害辨识与风险评价、文件汇编等环节在山西某矿山建立了安全标准化管理信息系统,在此基础上开发了与之相配套的、基于B/S和C/S混合模式的、在局域网上运行的应用软件--矿山安全标准化管理信息系统.系统由统一信息发布平台、即时报警系统、安全记录管理系统、统计分析系统等14个子系统组成.系统的应用提升了矿山安全生产整体水平,实现了矿山安全标准化和信息化.     

The Tea Party versus Agenda 21: local groups and sustainability policies in U.S. cities

As local governments have moved toward adopting sustainability policies, there have been some cases where local Tea Parties have emerged as aggressive and strident opponents of such changes. Looking broadly at the Tea Party movement across the United States and systematically measuring its influence in urban America, we assess each Tea Party chapter’s capacity – its ability to convert resources into meaningful political advocacy. Data is derived from surveys of political elites in 50 cities as well as from determining the level of sustainability programming in each of these same cities. Evidence demonstrates that the Tea Party has not had a significant impact on city policymaking in the area of sustainability. Rather, the typical Tea Party chapter appears to be at best a modest presence in local politics.     

The conversion of chicken manure to biooil by fast pyrolysis I. Analyses of chicken manure,biooils and char by 13C and 1H NMR and FTIR spectrophotometry

Fast pyrolysis of chicken manure produced two biooils (Fractions I and II) and a residual char. All four materials were analyzed by chemical methods, ¹³C and 1H Nuclear Magnetic Resonance Spectrometry (¹³C and 1H NMR), and Fourier Transform Infrared Spectrosphotometry (FTIR). The char showed the highest C content and the highest aromaticity. Of the two biooils Fraction II was higher in C, yield and calorific value but lower in N than Fraction I. The S and ash content of the two biooil fractions were low. The Cross Polarization Magic Angle Spinning (CP-MAS) ¹³C NMR spectrum of the initial chicken manure showed it to be rich in cellulose, which was a major component of sawdust used as bedding material. Nuclear Magnetic Resonance (NMR) spectra of the two biooils indicated that Fraction I was less aromatic than Fraction II. Among the aromatics in the two biooils, we were able to tentatively identify N-heterocyclics like indoles, pyridines, and pyrazines. FTIR spectra were generally in agreement with the NMR data. FTIR spectra of both biooils showed the presence of both primary and secondary amides and primary amines as well as N-heterocyclics such as pyridines, quinolines, and pyrimidines. The FTIR spectrum of the char resembled that of the initial chicken manure except that the concentration of carbohydrates was lower.     

碳源及反硝化芽孢杆菌强化低C/N比景观水体的生物脱氮

实验探讨了添加碳源及投加反硝化细菌对低碳氮比景观水体生物脱氮的影响。结果表明,有机碳源及B.subtilis FS05均能显著促进实验水体的生物脱氮作用,实验水体在28℃静置72 h后,乙醇添加组的TN、氨氮、硝酸盐及亚硝酸盐的去除率分别达到了62.7%、67.0%、69.8%和29.4%,而同样条件下,B.subtilis FS05投加组的去除率分别达到了66.9%、73.4%、66.0%和82.2%。从水质变化趋势可以看出,投加B.subtilis FS05能在更短时间内完成生物脱氮过程,其中,硝酸盐和亚硝酸盐去除速率最快,分别仅需要18 h和12 h。     

C/N和pH值对高温好氧反硝化菌产N2O的影响研究

以50℃高温、好氧条件下能进行高效好氧反硝化的菌株TAD1为研究对象,在不同C/N和pH值培养条件下,对其24 h的反硝化效率和反硝化过程中N2O的逸出量进行了研究。结果显示,C/N和pH值对菌株TAD1的反硝化效率和N2O产生量有明显影响.菌株TAD1最适宜的C/N为9,pH值为7,此时反硝化效率达到99.12%,N2O产生量仅为3.35×10-2 mg/L,N2 O转化率为0.045%,反硝化产物以氮气为主。另外,菌株TAD1不适宜在酸性条件下生长,pH值为6时反硝化效率为83.18%,N2O产生量为13.88×10-2 mg/L,是pH值为7时的4.14倍,是pH值为8时的5.07倍。     

Ce-PbO_2/C电极的制备及其去除水中酸性红B

采用电沉积法制备铈修饰的PbO2/C电极,通过SEM、XRD、XPS及循环伏安对PbO2/C、Ce-PbO2/C电极进行表征,结果表明,Ce-PbO2/C电极比PbO2/C颗粒细小,表面均匀致密,电化学氧化能力较强,修饰电极中Ce以CeO2的形态存在。以Ce-PbO2/C为工作电极,电解浓度为1 000 mg/L的高盐酸性红B模拟活性染料废水,考察了电压、pH、电解质浓度、极间距对脱色率、氨氮去除率及COD去除率的影响。确定适宜工艺条件为：初始酸性红B溶液浓度为1 000 mg/L,pH值为6,电压10 V,电解时间1 h,电极间距1.5 cm,该条件下脱色率、氨氮去除率和COD去除率分别为99.98%、97.23%和90.17%。通过UV-Vis及GC-MS初步分析了降解过程可能存在的中间产物及降解途径。     

碳源类型及进水量分配对CMICAO工艺脱氮除磷的影响

研究了分别以葡萄糖和乙酸钠为碳源时多点交替进水阶式A2/O(CMICAO)工艺氮磷的去除效果,以及在不同进水C/N比时各进水量分配对脱氮除磷效果的影响.结果表明,在相同的进水COD浓度下,乙酸钠比葡萄糖更适合作为碳源,更能提高脱氮除磷效率.以葡萄糖为碳源时,COD为200 mg/L、C/N比为5、缺氧池与厌氧池进水配比为1∶2时,出水COD、TN、氨氮和TP浓度分别为28.5、10.8、2.1和0.5 mg/L,均达到国家一级A排放标准.若采用葡萄糖作为碳源,投加量以使进水C/N比为5～7.5为宜,外加碳源时缺氧池与厌氧池进水分配比可统一采用1∶1.     

Contributions to ecological chemistry CXII balance of conversion of buturon‐14C in wheat under outdoor conditions 1

Abstract

The urea herbicide buturon (N‐[p‐chlorophenyl] ‐N’ ‐methyl‐N’ ‐isobutinyl‐urea), ¹⁴C‐labeled, was sprayed on winter wheat as an aqueous formulation (2.98 kg/ha) under outdoor conditions. Upon harvest (three months after application), a total of 49. 2% of the applied radiocarbon was recovered: 2.0% in the plants, 46.9% in the soil, and 0.3% in the leaching water (depth > 50 cm); less than 0.1% was in the grains (0.464 ppm). Only about half of the radioactivity present in plants could be recovered under mild extraction conditions; about half of this was unchanged buturon. In straw and husk extracts, the following metabolites were identified by gaschromatography/mass spectrometry: N‐(p‐chlorophenyl)‐N‐methyl‐O‐methyl‐carbamate (metabolite I), N‐phenyl‐N’ ‐formyl‐urea (metabolite II), two unstable metabolites giving (p‐chlorophenyl)‐isocyanate upon purification (metabolites III and IV), N‐(p‐chlorophenyl)‐N’ ‐methyl‐N’ ‐isobutenylol‐urea (metabolite V), p‐chloroformanilide (metabolite VI) and biologically bound p‐chloroaniline (metabolite VII). In the root and basal stem extract, the following metabolites were identified by gas chromatography/mass spectrometry: N‐(p‐chlorophenyl)‐O‐methyl‐carbamate (metabolite VIII) and N‐(p‐chlorophenyl)‐N’ ‐methyl‐urea (metabolite IX).