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Leaf wax molecular and isotopic ratios are generally considered robust isotopic pale-ohydrologic proxies. Here we evaluate the proxy value of the molecular distributions and hydrogen isotopic compositions of long chain n-alkanes (δDalk ) in surface peats collected from peatlands across a range of annual air temperatures from 1 to 15°C and a range of annual mean precipitation from 720 to 2070 mm in the monsoonal region of China. The alkane ratios (ACL and CPI) and δDalk values show relatively large variations in multiple samples from a single site, highlighting the complexity of these ratios at a small spatial scale. In the montane Zoigê peatland, the apparent fractiona-tion between precipitation and δDalk is more positive than in the other six sites, which is possibly an effect of the higher conductivity of the water in this high elevation site (3500 m a.s.l.). At a larger spatial scale, the site-averaged CPI ratios and the δDalk values of n-C29 and n-C31 alkanes show significant correlation with the air temperature and precipitation. These results support the application of the CPI ratio and the δDalk ratios of n-C29 and n-C31 alkanes as sensitive paleohydrologic proxies on millennial and larger timescales. [ABSTRACT FROM AUTHOR]

PM2.5 is an important global air pollution issue. PM2.5 causes various problems on the environment and human health. Even though PM2.5 of the outdoor air is eliminated by particulate air filters, the chemicals adsorbed on the filtered PM2.5 can be outgassed and introduced into the semiconductor manufacturing facilities and processes, thus causing defects on the semiconductor chips by producing particles and haze as airborne molecular contamination. Therefore, estimating the amount of the outgassing from PM2.5 is a very important factor to control gaseous contaminants in the semiconductor industry. In this paper, the PM2.5 samples at different PM2.5 mass loadings were collected in Xi’an, China and evaluated using the soft X-ray radiolysis method for determining the relation between the outgassing and the PM2.5 mass loading. The PM2.5 samples were also analyzed by several methods for quantifying organic and elemental carbons, water soluble ions, and organic compounds in the PM2.5 samples. The outgassing measured by the soft X-ray method increased linearly with the PM2.5 mass loading, and the chemical analyses explained that the organic carbon (OC) was dominantly detected by the soft X-ray method in the current study. Moreover, the sampling location of the PM2.5 affected on the organic compounds of the PM2.5. [ABSTRACT FROM AUTHOR]

• Decarbonisation of the industrial sector is key to achieve net-zero emission target on schedule. • For the cement and iron and steel industry, some new technologies which based on their production material(CaO, steel slag) have been gradually developed. • The economic benefits generated by chemical industry can promote the application of carbon reduction technologies in other fields. • The small-scale projects can reduce economic costs through enhancing regional synergy. With the continuous increase in anthropogenic CO 2 emissions, many countries have researched and implemented carbon reduction technologies for large-scale industrial processes. In addition to the power industry, the cement, steel and iron, and chemical production industries are large sources of CO 2 emissions. However, the processes and flue gas characteristics of each industry differ; thus, the carbon capture methods applicable to each industry differ. This paper reviews the key technologies, status, and development trends of carbon reduction methods for each industrial source with a focus on the unique characteristics of each industry. As emission reduction targets become stricter, the large-scale development of carbon reduction demonstration projects will inevitably lead to a decrease in the costs of emission reduction technology. This review would be useful for obtaining an overview of the current progress and future prospect for carbon reduction of nonpower industries in both fundamental research and commercial applications. [ABSTRACT FROM AUTHOR]

Daily exposures to chemicals in drinking water are of importance in risk assessment to human health. However, exposure assessment of chemicals in drinking water has seldom been performed in China. Until now, no such a detailed exposure assessment was reported in China. The aim of the present paper is to describe the scenes of daily exposure to Cu and Zn in drinking water by the population of Shanghai, China in the summer of 2003. A total of 163 volunteers and/or homes were selected to be statistically representative of the population of Shanghai, China. The Modified Consumption Habit Exposure Model (CHEM) method combined with the measurement of metals concentrations in stagnant water and actual ingested water was used to describe the daily exposure. The Consumption Habit Exposure Model method results showed that water consumption ranged from 1.7 to 2.2 L/day, varied with different age, gender and work location groups. Chemical results showed that the average Cu and Zn concentrations in stagnant water were much higher than those in actual ingested water (13.5 μg/L and 1.55 mg/L vs. 10.8 μg/L and 0.29 mg/L). Exposure assessment results also showed that volunteers had the highest exposure from the time of after breakfast to before dinner, and had the lowest exposure during the 15 minutes before sleeping. It was also showed that there were few volunteers directly exposed to stagnant water, although six hours stagnant time can be reached in most of the homes in Shanghai in the morning. The mean daily exposures to Cu and Zn were 0.36 μg/kg/day and 0.01 mg/kg/day. Daily intakes of Cu and Zn from drinking water by Shanghai people were 1.8% and 4.4% of the World Health Organization recommendations for minimum total intakes of Cu and Zn for adults, respectively. [ABSTRACT FROM AUTHOR]

The following paper is based in part upon a workshop chaired by the author at the 6th Annual Generic Drug Summit (http://www.iirusa.com/genericsummit/). in Washington, DC, USA, on 28th September. The title of the workshop was ‘Strategic Sourcing in the generic drug industry in the US’. One of the objectives of the workshop was to examine the trend in the level of activity of API manufacturers in developing products for the US market and to discuss some basic principles that the sourcing manager can apply to make good business decisions sourcing APIs for the generic pharmaceutical company. [ABSTRACT FROM AUTHOR]

This paper presents the preliminary results of a modeling study on regional air pollutants transport over the Pearl River Delta (PRD) region of China in fall season (Nov. 2002) on the basis of compiled emission inventories. The advanced regional chemical transport model, STEM-2K1, driven by meso-scale meteorological model MM5, was employed with a nesting technique. Three weather patterns were found in the fall season. Numerical sensitive study indicated that external influence on air quality in PRD was significant and dependent on the transport pattern determined by weather situations. [ABSTRACT FROM AUTHOR]

The purpose of this investigation is to evaluate the current status and identify the problems of municipal solid waste (MSW) management in China in order to determine appropriate remedial strategies. This is the first of two papers, discussing primarily the general characteristics of MSW and its management in China. The second paper focuses on specific remedial strategies. MSW generation in China has increased rapidly in the past 20 years from 31.3 million tons in 1980 to 113.0 million tons in 1998. The annual rate of increase is 3-10%. The average generation per capita is 1.0 kg/day (0.38 t/year). Nearly one-half of the waste generated is dumped in the suburbs, where the accumulated quantity has reached 6 billion tons, which has caused heavy environmental pollution. This paper provides information on MSW management in China, such as MSW generation and its physical, chemical, and biological properties. Low calorific value and high moisture content characterize China's municipal waste. Other issues related to MSW management in China are also discussed, including the factors that influence MSW generation quantity and quality, MSW collection, transfer and transport, treatment and disposal, material recovery, legislation, enforcement, and administration. [ABSTRACT FROM AUTHOR]

This paper examines the current status of Pak-China commercial cooperation, the convergence of this cooperation towards the realisation of China-Pakistan Economic Corridor (CPEC), and the challenges and opportunities envisioned for this relationship. Constructivism is the best possible characterisation of the nature of Pakistan's commercial relations with China, as these do not amount to a zero-sum regional game that would seek maximisation of power at the cost of their Asian neighbours. The current trajectory of Beijing-Islamabad relations transcends the geopolitical and geo-economic expediencies that could beckon prosperity and economic cooperation. Both countries have an interest in creating an enabling security, political, and trade environment for the envisioned growth and sustainability of their commercial relations. An environment of peace and stability will not happen in a vacuum, especially if other regional and extra-regional powers are not willing to tango. For the first time in Pakistan's history, its territory shall set a course of economic cooperation rather than geopolitical competition. The CPEC is not only the pivot of Pakistan-China politico-economic relations, but holds similar promise for the region and beyond. In the aforementioned context, the paper explains multifarious economic and trade linkages between the two countries, and proffers recommendations for deepening commercial cooperation through optimisation of trade balance, export diversification, and foreign direct investment (FDI) inflows. [ABSTRACT FROM AUTHOR]

Abstract: Vehicle populations in China have been increasing sharply since 1990s. Vehicle emissions including various gaseous pollutants and particulate matter cause deterioration of air quality. However, measurements of particulate mater from on-road vehicles in China are scarcely reported, and thus the chemical compositions of particles emitted from vehicles in China are unknown. In this research, tunnel experiments were performed to measure PM2.5 in the Wutong tunnel, Shenzhen, China. Detailed PM2.5 chemical compositions, with organic compounds determined by GC/MS, in the tunnel were presented. Elemental carbon and organic matter composed 63% and 34% of the total PM2.5 mass in the Wutong tunnel, respectively. Alkanes, PAHs, hopanes, fatty acids, and dicarboxylic acids were the major identified organic compounds, and their source profiles in the PM2.5 in the Wutong tunnel were characterized. The comparisons of our measurements with those in the literature were also made to demonstrate the characteristics of the vehicle source profiles in the Wutong tunnel. The experimental results in this paper can improve understanding of particulate matter emitted from vehicles in China. [Copyright &y& Elsevier]

Abstract: In this paper, chemometric approaches based on correlative analysis, hierarchical clustering, classical and robust principal component analysis were investigated to characterize the quality of the atmospheric environment in Hong Kong. Since the weather behaved quite atypically as concerns both the rains and temperature during the sampling period, it is difficult to clarify the relationship between the chemical species, weather and the environmental quality with the raw data directly. However, with the help of suitable chemometric methods, the correlationship between samples or variables could be investigated. Moreover, pattern recognition based on hierarchical clustering, classical and robust principal component analysis could provide a visual aid for identifying the homogeneity and/or differences of the samples under study. The successful applications to 55 coarse and fine particulate observations from the atmospheric environment in Hong Kong showed that chemometric approaches could develop a clear picture concerning the correlation between samples or variables and especially the linkage of the chemical components, weather and the environmental quality for the atmospheric system with much complexity. [Copyright &y& Elsevier]

The table of contents for the November 2013 issue of the journal "Journal of the Chinese Chemical Society," is presented.

Background: In China, Atractylodes macrocephala is mainly distributed in Zhejiang province. It is, therefore, desirable to determine a reliable and accurate methodology to differentiate the samples collected from Zhejiang province. Although some studies on the fingerprints of Atractylodes macrocephala using HPLC have been published, none of them compared the processed product of Atractylodes macrocephala from different areas of Zhejiang province. Materials and Methods: Reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with hierarchical cluster analysis was employed in the fingerprint analysis of Atractylodes macrocephala from Zhejiang province, China. The LC assay was performed on a reversed-phase C18 column with linear gradient elution using water and acetonitrile. The LC data showed considerable variation of chemical constituents among Atractylodes macrocephala populations. Results: 21 and 22 characteristic peaks in the 14 grants of Atractylodes macrocephala and its processed product were determined in samples from different habitats of Zhejiang province, respectively. Their chromatographic patterns were generally consistent although their contents of chemical compositions were greatly different. The results of hierarchical cluster analysis showed that the samples could be divided into four groups; it was able to select excellent resources from the groups. Conclusion: This was the first report of hierarchical cluster analysis of crude and processed Atractylodes macrocephala according to their chemical fingerprints and could be applied to the intrinsic quality control of crude and processed Atractylodes macrocephala. The processing technique of Atractylodes macrocephala through the pilot-scale experiment was first studied and is simple and suitable for prepared yin pian of Atractylodes macrocephala industrial manufacture. [ABSTRACT FROM AUTHOR]

n ongoing project monitors saline dust transportation and accumulation in the Western Junggar Basin to determine the rate and chemical composition of dust inputs to soils and their impact on snow/ice melt and vegetation degradation of the surrounding areas. The 1-year record from ten dust trap sites in the Ebinur region of northwest China reveals that yearly deposition rates fluctuate strongly between different sampling sites. The mass accumulation rates (fluxes) of the dust, including water-soluble solutes and trace element, range from 79 to 381 g m year. With increasing distance from the dry lake bed, dust deposition gradually decreases. The salinity of the dust ranges from about 43 to 185 g kg and the mass-soluble salt fluxes range from 4 to 61 g m year. The types of water-soluble salt are different at different sampling sites. In all samples, the major types of water-soluble salts in the dust are sulfates and chlorides. Sulfate and chloride are the major anions while sodium and calcium are the main cations, and nitrate was not found in any dust samples. Potentially toxic trace elements such as Cd, Cr, Pb, Mn, As, Cu, and Ni are present in all samples, with high levels of Cr, Pb, Mn, Cu, and Ni. The dust is a chemical dust in that it consists of dense fine sulfates, chlorides and potentially toxic elements, and causes serious air pollution, resulting in soil salinization and vegetation degradation and accelerating snow/ice melt. [ABSTRACT FROM AUTHOR]

A commentary on the past, present and future of chemical engineering in China is presented. According to the authors, the modern chemical industry started in the 19th century. They discussed the history of the chemical industry in China. They looked at the progress made in the various branches of chemical engineering including chemical and petrochemical industries, coal chemical chemistry, and fine chemicals and materials manufacture.

One-minute PM2.5 concentration was obtained with LD-5C pocket microcomputer laser dust instrument from Dec. 15th, 2005 to Jan. 16th, 2006 and Mar. 17th to Apr. 28th, 2006 in Beijing. The concentration of SO2, NO2, O3, CO, and PM10 from Jan. 1st, 2001 to Dec. 31st, 2004 were obtained from the conversion of air pollution index. Results showed that all the pollutants showed cyclic characteristics. The longer yearly cycles was shown from SO2, NO2, O3, CO, and PM10, as the sampling time was 4-year long and daily collected. The shorter hourly and daily cycle was shown from 1-min PM2.5, as the sampling time was about 1-month long and one collected at 1 min. The spectral density analysis confirmed this from the periodogram graphs. The longer yearly cycle (365, 180 days), the seasonal cycle (120, 60–90 days), and monthly cycle (21, 23, 27 days) of SO2, NO2, CO, O3, and PM10 were obviously shown. In addition, the shorter weekly cycle of 5–7 days is obviously shown, too. The shorter hourly cycle (8–12, 4–6, 3, 1–2 h, 20 min) of 1-min PM2.5 was also indicated from spectral density analysis. Two major factors contribute the 1-min PM2.5 cycles, i.e., the meteorological factors and source effects. Both the relative humidity and dew point showed consistent variation with PM2.5, but the wind speed showed inverse variations with PM2.5. Furthermore, the spectral density analysis of the meteorological factors (4–5, 2–2.5, 1–1.5 days, 12, 6–8, 3 h) may partially explain the cycles of PM2.5. As for the sources effects, it can be shown from the strong dust storm of April 16–18th, 2006. PM2.5 constantly increased tens and even hundreds of times high concentration within a few minutes due to the intensity of the dust sources. [ABSTRACT FROM AUTHOR]

Aspergillus versicolor D-1 was employed to convert dehydrocostuslactone (1) and 3-hydroxy-1(10),3,11(13)-guaiatriene-12,6-olide-2-one (5) stereoselectively. The reactions occurring were specific hydrogenation on the exocyclic α,β-double bond of sesquiterpene lactones with excellent conversion. Products were identified by the analysis of their spectra such as UV, IR, MS, 1H, 13C NMR, and NOESY, and the structure of one new compound was elucidated. The characteristic of the stereoselective hydrogenation was also discussed and suggested. [ABSTRACT FROM AUTHOR]

The occurrence and environmental risk of endocrine-disrupting chemicals was investigated in the surface water samples of the Zhujiang and Dongjiang rivers, Pearl River Delta (PRD) of South China. Thirty surface water samples were collected in the dry season and analyzed by using an MSTFA derivation and a GC-MS-SIM method. Concentrations of biphenol A (BPA) ranged from 43.5 to 639.1 ng L − 1, and concentrations of estrone (E1) and 17β-estradiol (E2) ranged from <1.5 to 8.2 ng L − 1 and from <1.1 to 1.7 ng L − 1, respectively. The spatial distribution of these chemicals was related to the discharge of domestic and industrial wastewater along the rivers. The highly significant correlation among BPA, E1, and dissolved organic carbon (DOC) might be related to their same contamination source and/or their association with colloidal organic carbon of DOC in the river samples. Compared with other studied rivers in the world, the estrogenic contamination in the investigated rivers was high for BPA and moderate for E1. As the average estrogenic activity in E2 activity equivalent (E2eq; 1.16 ng E2eq L − 1) for the target BAP, E1, and E2 combined with those for nonyphenol and octylphenol, which were previously reported, exceeds documented effect levels in the investigated river waters for some aquatic species, they may pose a high risk to the local aquatic organisms. [ABSTRACT FROM AUTHOR]

Sequential extraction integrated with isotope analysis was carried out on a sediment core from Liaodong Bay, northeast China, for characterizing Pb in various extraction phases and its possible sources. Results show that in all extracted fractions Pb concentrations increased abruptly in the top part of the sediments that deposited after 1980, but remained lower and rather constant before 1980. Consistent with the variation pattern of Pb concentration, the 206Pb/207Pb ratio displays a dramatic decrease around 1980. These findings strongly suggest serious Pb pollution since then. The Pb concentration and the isotopic ratios of 206Pb/207Pb and 208Pb/207Pb in the residual fraction show rather small changes through the entire core, and are similar to those of uncontaminated Chinese loess, possibly representing the characteristics of the regional geogenic background. The isotopic ratios of the sediments before 1980 varied in different extracted fractions with a linear pattern, from the residual at the highest toward the average signature of automobile exhausts and Pb-Zn deposits, implying a prominent two-end member mixing style of the Pb origin; one is the regional geologic background and the other is anthropogenic sources. The difference in isotopic ratios between the extractions might be indicative of varied proportions of the two sources. For sediments after 1980, however, the isotope ratios in nonresidual fractions are all relatively low and show little differentiation, which may suggest that polluted Pb dominates all the extracted fractions for the top part of the core. [ABSTRACT FROM AUTHOR]

The increasing use of industrial biotechnology by the Chinese liquid biofuels and chemical industries is expected to help offset energy security and environmental concerns generated by China's robust economic growth. The expanding use of bioprocesses to produce products such as fuel ethanol and bioplastics is also likely to contribute to continued innovation, productivity gains, and cost savings. This, combined with strong government promotion of the country's bio-based economy, coincides with the two industries' growing global prominence; China is currently the world's third largest producer of ethanol and second largest producer of chemicals. This growth has encouraged expanded domestic and foreign investment, including in bio-based projects, and generated related gains in exports, particularly in the chemical industry. Market conditions facing many ongoing and prospective ventures, however, are changing as a result of a combination of factors, including the strength of the Chinese currency, new labor regulations, tax changes, and volatile energy prices. [ABSTRACT FROM AUTHOR]

A 3-D regional chemical transport model, the Nested Air Quality Prediction Model System (NAQPMS), with an on-line tracer tagging module was used to study the source of the near-ground (<1.5 km above ground level) ozone at Mt. Tai (36.25° N, 117.10° E, 1534ma.s.l.) in Central Eastern China (CEC) during the Mount Tai experiment 2006 (MTX2006). The model reproduced the temporal and spatial variations of near-ground ozone and other pollutants, and it captured highly polluted and clean cases well. The simulated near-ground ozone level over CEC was 60-85 ppbv (parts per billion by volume), which was higher than values in Japan and over the North Pacific (20-50 ppbv). The simulated tagged tracer data indicated that the regionalscale transport of chemically produced ozone over other areas in CEC contributed to the greatest fraction (49%) of the near-ground mean ozone at Mt. Tai in June; in situ photochemistry contributed only 12%. Due to high anthropogenic and biomass burning emissions that occurred in the southern part of the CEC, the contribution to ground ozone levels from this area played the most important role (32.4 ppbv, 37.9% of total ozone) in the monthly mean ozone concentration at Mt. Tai; values reached 59 ppbv (62%) on 6-7 June 2006. The monthly mean horizontal distribution of chemically produced ozone from various ozone production regions indicated that photochemical reactions controlled the spatial distribution of O3 over CEC. The regional-scale transport of pollutants also played an important role in the spatial and temporal distribution of ozone over CEC. Chemically produced ozone from the southern part of the study region can be transported northeastwardly to the northern rim of CEC; the mean contribution was 5-10 ppbv, and it reached 25 ppbv during high ozone events. Studies of the outflow of CEC ozone and its precursors, as well as their influences and contributions to the ozone level over adjacent regions/countries, revealed that the contribution of CEC ozone to mean ozone mixing ratios over the Korean Peninsula and Japan was 5-15 ppbv, of which about half was due to the direct transport of ozone from CEC and half was produced locally by ozone precursors transported from CEC. [ABSTRACT FROM AUTHOR]

The shallow groundwater in Hangzhou area has the characteristics of high mineralization, high salinity and high contents of iron and manganese. Statistical analyses and the experiments of simulation show that the Holocene transgressive strata has a crucial effect on the formation of chemical composition of the shallow groundwater in the plain area of Hanghzhou. The degree of transgression is in consonance with the variation tendency of the thickness of the transgressive strata. The chemical compositions of the subsurface water in the hilly area depend on the lithology of the aquifers. [ABSTRACT FROM AUTHOR]

The article reports on the groundwater crisis in China and discusses the contamination of chemicals with groundwater.

The article examines the chemical composition of Rhododendron primulaeflorum in China. It notes that the leaves and flowers of this plant help clear away heat, tonify the kidney, and is used for detumescence. Among the compounds identified from the plant include umbelliferone, lyoniside, scopoletin, and ssioriside. It points out that this investigation justifies the therapeutic effect of the plant.