Peng Zicheng

Health Effects of Arsenic, Fluorine, and Selenium from Indoor Burning of Chinese Coal

Chinas economy has developed rapidly in the last two decades, leading to an increase in energy consumption and consequently emissions from energy generation. Coal is a primary energy source in China because of its abundance and will continue to be used in the future. The dominance of coal in energy production is expected to result in increasing levels of exposure to environmental pollution in China. Toxic trace elements emitted during coal combustion are the main sources of indoor air pollution. They are released into the atmosphere mainly in the forms of fine ash and vapors and have the potential to adversely affect human health. Those trace elements, which volatilize during combustion, are hazardous air pollutants (HAPs) and are particularly rich in Chinese coals. Among the HAPs, arsenic (As), fluorine (F), and selenium (Se) have already been identified as pollutants that can induce severe health problems. In this review, the geochemical characteristics of As, F, and Se, including their concentration, distribution, and mode of occurrences in Chinese coal, are documented and discussed. Our investigations have confirmed the current As- and F-induced epidemics in Guizhou (Southwest China) and Se epidemic in Hubei (Northeast China). In this study, diagnostic symptoms of arseniasis, fluorosis, and selenosis are also illustrated.

The longevity of subcontinental lithospheric mantle beneath Jiangsu-Anhui Region ——The Os isotope model age of mantle-derived peridotite xenoliths

The basalt-borne peridotite xenoliths from Jiangsu-Anhui provinces were analyzed for whole rock Os isotopic compositions in two laboratories of USTC, China and CRPG, France, respectively. The187Os/188Os ratio of the sample set ranges from 0.119 to 0.129 (25 samples, USTC) and from 0.117 to 0.131 (17 samples, CRPG). The Os isotopic compositions of most samples are less than 0.129 and depleted relatively to the primitive mantle, showing a good correlation with the major element compositions. With the187Os/188Os-Al2O3 alumichron, the samples yield a model age of 2.5 ± 0.1 Ga (data of USTC) and 1.9 ± 0.1 Ga (data of CRPG), late Archean to early Pro-terozoic. The two samples with the lowest187Os/188Os ratio (0.119 and 0.117) have the TRD (Re depleted age) of 1.1 Ga (USTC) and 1.4 Ga (CRPG), mid-Proterozoic. The Os isotope model age shows that the peridotite xenoliths from Cenozoic alkali basalt in Jiangsu-Anhui provinces have an old formation age (early- to mid- Proterozoic). They are not newly produced mantle after the Phanerozoic replacement of the lithosphere mantle, but residual fractions of Proterozoic mantle.

ESR dating of tooth enamel: comparison with U-series, FT and TL dating at the Peking Man site

Deer tooth samples from Zhoukoudian, the Peking Man Cave, were studied. Non-linear fitting is used to determine AD, from which ESR ages were calculated by both the disequilibria model (DU) and linear uptake model (LU). Comparison of ESR ages with those from U-series, FT and TL methods show that the enamel of deer teeth is a suitable material for ESR dating.

High-precision timing of the Quaternary standard samples with thermal ionization mass spectrometry (TIMS) U-series method

Two national stalagnlite standards (GBW04412, GBW04413) and one international coral standard (RKM-4) have been determined by using thcrmal ionization mass spcctrometry (TIMS) method. The values of (234U/238U)act, (230Th/234U)act and age are all consistent in error range with thc stantlard values obtained by using α spectrometry.Two national stalagnlite standards (GBW04412, GBW04413) and one international coral standard (RKM-4) have been determined by using thcrmal ionization mass spcctrometry (TIMS) method. The values of (234U/238U)act, (230Th/234U)act and age are all consistent in error range with thc stantlard values obtained by using α spectrometry.

Temporal variations of heavy metals in coralPorites lutea from Guangdong Province, China: Influences from industrial pollution, climate and economic factors

The eight heavy metals Cr, Mn, Co, Ni, Cu, Zn, Cd, and Pb have been determined in samples of coralPorites lutea collected from Dafangji Island waters (21°21′N, 111°11′E), Dianbai County, Guangdong Province, China, by the ICP-MS method. The samples represent the growth of coral in the period of 1982–2001. The results showed that the waters were polluted by the heavy metals Cu, Ni, Zn, and Pb in certain years, but not by other metals. The contamination may have come from industrial sources, including electroplating, metallurgy, mining, and aquatic industries in the coastal areas.The correlation coefficients among the metals and climatic and economic factors indicate that the metals Ni, Zn, and Cd behave similarly. Copper and Mn are positively correlated, and cobalt is negatively correlated with Cr, Ni, Zn, and Cd. Lead is not correlated with any other metals but is correlated with sea surface water temperature, air temperature, GDP and industrial-agricultural production in Dianbai County. Lead in corals is related to the enhanced pollution level of ocean waters as a result of increased industrial activities.

Estimation of the influence of experimental conditions on ESR dating results

Abstract Rapid progress has recently been made in ESR dating, a new dating technique. Much attention has been paid to the accuracy of its results, as errors may be caused by various factors. This paper probes into the influence of the applied microwave power and the absorbed dose rate of additional radiation. A few measurements we made with carbonate and quartz samples reveal that the microwave power saturation point depends on the type of paramagnetic centers and the type of samples. The microwave power and the dose rate of additional radiation have an apparent effect on the total radiation dose assessment in such samples. Extrapolating on a logarithmic scale, we determine that the ESR age of coral sample 87-04 is (3.64 ± 0.55) ka as microwave power is zero. This is in accord with its 14 C age (3.75 ± 0.19) ka.

Characteristics of coal ashes in Yanzhou mining district and distribution of trace elements in them

In the process of combustion of coal organic and inorganic materials in it will undergo a complex variation. Part of them will become volatiles and, together with coal smoke, enter into atmosphere, some will remain in micro-particulates such as ash and dust and find their way into atmosphere in the form of solid particles, and the rest will be retained in ash and slag. Coal ashes are the residues of organic and inorganic substances in coal left after coal combustion and the composition of coal ashes is dependent on that of minerals and organic matter in coal. This paper deals with the chemical composition of coal ashes, the distribution of trace elements in them and their petrological characteristics, and also studies the relationship between the yield of coal ashes and the distribution of trace elements. In addition, a preliminary study is also undertaken on the factors that affect the chemical composition of coal ashes. As viewed from the analyses of coal ash samples collected from the Yanzhou mining district, it can be seen clearly that coal ashes from the region studied are composed chiefly of crystalline materials, glassy materials and uncombusted organic matter and the major chemical compositions are SiO2, Al2O3, Fe2O3, and CaO, as well as minor amounts of SO3, P2O5, Na2O, K2O and TiO2. During the combustion of coal, its trace elements will be redistributed and most of them are enriched in coal ashes. At the same time, the concentrations of the trace elements in flying ash are much higher than those of bottom ash, i.e., with decreasing particle-size of coal ashes their concentrations will become higher and higher. So the contents of trace elements are negatively proportional to the particle-size of coal ashes. There has been found a positive correlation between the trace elements Th, V, Zn, Cu and Pb and the yield of coal ashes while a negative correlation between Cl and the yield of coal ashes.

Monthly sea surface temperature records reconstructed by δ18O of reef-building coral in the east of Hainan Island, South China Sea

Stable oxygen isotopic compositions of a coral colony ofPorites lutea obtained on a core allowed the reconstruction of a 56-a (1943–1998) proxy record of the sea surface temperatures. This coral δ18O data are from the east of Hainan Island water (22°20’N, 110°39’E), South China Sea. The relationship between δ18O in the skeletal aragonite carbonate and the sea surface temperature (SST) is SST = -5.36 δ18OPDB-3.51 (r = 0.73,n = 470), dδ18O/d(SST) = -0.187‱/ °C; and the thermometer was set at monthly resolution. The 56-a (1943–1998) proxy record of the sea surface temperatures reflected the same change trend in the northern part of South China Sea as the air temperature change trend in China.

Study on comparison of ESR dating of coral and shells with 230Th/234U and 14C methods

Abstract The ESR technique was available to date samples of coral and shells. The signal at g = 2.0007 seems to be suited for this task. ESR age of the coral sample at South Sea is 4.09 ± 0.61 ka, which is within the range of 5.0 ± 0.2 and 3.75 ± 0.19 supplied by the 230 Th/ 234 U and 14 C methods, respectively, being somewhat nearer to the 14 C age. ESR age of the shell at Baoyu island is 1.66 ± 0.25 ka by the exponential fit as given according to the occurrence of saturation of ESR intensity vs added γ-ray dose. It is concordant with the value 1.69 ± 0.09 ka ( 14 C). The other two shells from the upper and low layers of Baishakou sand barrier gave ESR ages of 3.90 ± 0.59 and 7.94 ± 0.95 ka, respectively, which compare with those of 3.77 ± 0.10 and 6.83 ± 0.12 ka, respectively, given by the 14 C method.

K-Ar ages and Pb, Sr isotopic characteristics of Cenozoic volcanic rocks in Shandong Province, China

Abstract28 samples of Cenozoic volcanic rocks collected from Shandong Province have been dated by K-Ar method. They are mainly Neogene with an age range of 4–19 m. y. The basalts from Linqu and Yishui in west Shandong Province are Miocene and those from Penglai and Qixia in east Shandong Province are Miocene and Pliocene in age. The basalts from Wudi in north Shandong Province are Middle-Early Pleistocene in age. In each area the duration of volcanic eruption was estimated at about 2–3 m. y.Pb and Sr isotopic compositions and U, Th, Pb, Rb, Sr, and major elements in most of the samples were determined. The isotopic compositions are:206Pb/204Pb—16.92-18.48,207Pb/204Pb—15.30-15.59,208Pb/204Pb—37.83-38.54, and (87Sr/86Sr)i—0.70327-0.70632. There are some positive or negative linear correlations between206Pb/204Pb and207Pb/204Pb, Pb isotopes and Pb content, Pb isotopes and Sr isotopes, and Sr isotopes and other elements. The basaltic rocks from east and west Shandong Province have somewhat differences in isotopic composition and element content. The basalts probably are products of multi-stage evolution of the mantle. They have preserved the primary features of the source, although they were influenced, to some extent, by the contamination of crustal materials.