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Progress of gastric cancer etiology:N-nitrosamides in the 1990s

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World Journal of Gastroenterology 2000年第4期6卷 613-618页

作者： Da Jun Deng Laboratory of Cancer Etiology,beijing Medical university school of Oncology& beijing Institute for Cancer Research,100034,china 北京医科大学北京

Stomach carcinoma is still the leading cause of cancer death in china and the second one in the world. Its possible causes include: A) chemical factors such as intragastric formation of N-nitroso compounds (NOC) and high salt intake; B ) biological factors such as infection of Helicobacter pylori and biotoxins intake; and C ) nutritional factors such as deficiency of vitamin C, selenium, and other antioxidants. Nitrogenous precursors of NOC, e.g., alkylamines, alkylureas, alkylguanidines, and alkylamides, occur widely in nature and potential nitrosating agents, e.g., nitrite (NO2-) and NOx (the gaseous oxides of nitrogen ) are similarly widespread. Relationship between exposure to NOC and causes of human cancer was investigated extensively ten years ago. Results indicated that the exposures of NOC might contribute to the occurrences of malignancy in the upper digestive tracts including stomachs. It was also observed that both high salt intake and deficiency of some micronutrients enhanced NOC-induced carcinogenicity. Recent studies show that infection of H. pylori can lead to atrophic gastritis and achlorhydria, and promote endogenous formation of NOC indirectly[1] . Much attention has been paid to stomach cancer and NOC regarding the characterization of natural N-nitrosamides in human environment in the 1990s.

关键词： stomach neoplasms/etiology nitroso compounds nitrosamides/nitrosourea epidemiology chromatography liquid microorganisms

Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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Science china Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2, HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. College of Chemistry and environment Science, Hebei university, Baoding 071002, china 2. International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, china 3. College of Physics Science and technology, Hebei university, Baoding 071002, china College of Chemistry and environment Science Hebei University Baoding China International Center for Materials Physics Chinese Academy of Sciences Shenyang China College of Physics Science and technology Hebei University Baoding China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

TiO_2-assisted photo-catalysis degradation process of dye chemicals

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Journal of environmental Sciences 2001年第1期13卷 64-68页

作者： LI Fang\|bai 1,2 , GU Guo\|bang\+2, HUANG Guo\|feng\+1, GU Yun\|li\+2, WAN Hong\|fu\+1 (1.Guangdong Institute of Eco\|environment and Soil Science,Guangzhou 510650, china. E\|mail: fbli@*** 2.College of chemical engineering, South Technolog Guangdong Institute of Eco-environment and Soil Science Guangzhou 510650 China. E-mail:[email protected] College of chemical engineering South Technology University Guangzhou510642 China

The photo-catalytic degradation pathway and degradation products of methylene blue, rhodamine B, methyl orange, and malachite green in aqueous TiO2 suspension irradiated by high pressure mercury lamp by means of UV-visible absorption spectra and ion chromatography were investigated. The photo-catalysis degradation of dye solutions with charges was greatly effected by pH value owing to the electrostatic model. The photo-degradation rate of dyes anion increased with the decrease of pH value, in contrast, the photo-degradation rate of dyes cation increased with the increase of pH value. And the absorption peaks diminished with a blue shift. After illuminated for 30 minutes, a part of dye chemicals were completely mineralized and transferred into inorganic species including chloride ion, ammonium ion, nitrate ion, sulfate ion. And the addition of 100 mmol/L H2O2 promoted the formation of inorganic species. In this study, the quantity of ammonium ion was much more than that of nitrate ion. That indicated the formation of nitrate is from ammonium. The purification rate of COD in four kinds of dye solution was 71.7%-88.7%. The decrease of COD of dyes solution implies the feasibility of the environmental application of photo-catalyzed process.

关键词： Chromatography Irradiation Mercury vapor lamps pH effects Photocatalysis Spectrum analysis Titanium oxides

Goaf Purifying Characteristic of Mine Water with High Turbidity,High Concentration of Iron and Manganese

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Goaf Purifying Characteristic of Mine Water with High Turbid...

KINETIC FEATURES OF HYDROCARBON GENERATION OF DESMOCOLLINITE FROM LATE PERMIAN COALS IN SOUTH china

2011 International Symposium on Water Resource and environmental Protection(ISWREP 2011)

作者： SHAO Li-nan YANG Xiao-song Institute of environmental engineering beijing General Research Institute of mining Metallurgy beijing china HE Xu-wen school of chemical and environmental engineering china university of mining and technology(beijing) beijing china

Taking mine water with high iron and high manganese as research object, kinetic parameter experiment were carried out by goaf filling. The result shows that dispersion coefficient and adsorption coefficient of goaf filling are D 3.12m 2 /d, K d Fe =11.07mL/g, K d Mn =7.543mL/g respectively;Iron and manganese desorption rate is very low in goaf filling, and the highest desorption rates of iron, manganese are 29.29% and 33.85% respectively;Based on experiment result, iron and manganese fixed state adsorption capacity are 119.915μg/g, 68.6μg/g respectively.

关键词： goaf purifying high turbidity high concentration of iron and manganese mine water

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Scientia Geologica Sinica 2000年第1期 97-102页

作者： Sun Xuguang and Wang Guanyu (Department of Geology Peking university, beijing 10087) Hao Duohu and Jin Kuili( beijing Graduate school, china university of mining and technology beijing 100083)

The kinetic parameters of hydrocarbon generation from coals or kerogens, can indicate the structure of their internal molecular. The structure has been extensively studied by laboratory experiments. In this paper, Rock-Eval II were carried out on desmocollinite, which is isolated from Late Permian coals in Shuicheng, Guizhou Province in southern china. The determination of the kinetic parameters shows that the activation energies are correlated with chemical structures. The desmocollinite show a broader distribution of activation energies, thus reflecting a more complex composition. The average activation energy of barkinite, desmocollinite and fusinite are 177 kJ/mol, 200 kJ/mol and 360 kJ/mol. Respectively. We can conclude that the order for the three macerals to form oil is barkinite -vitrinite -fusinite.

关键词： rock KINETIC FEATURES OF HYDROCARBON GENERATION OF DESMOCOLLINITE FROM LATE PERMIAN COALS IN SOUTH china

EFFECT OF WEAK INTERACTIONS ON PHENOL ADSORPTION FROM AQUEOUS SOLUTIONS BY AMINATED POLYMERIC ADSORBENTS

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Chinese Journal of Polymer Science 2006年第1期24卷 61-66页

作者： Wei-ming Zhang Jin-long Chen Ai-min Li Bing-cai Pan Qun Chen Ming-yang He and Quan-xing Zhang a State Key Laboratory of Pollution Control and Resources Reuse,school of the environment,Nanjing university,Nanjing 210093,china b Research Center for engineering technology of Organic Poison Control and Resources Reuse in Jiangsu Province,Nanjing 210038,china c Department of chemical engineering,Jiangsu Polytechnic university,Changzhou 213016,china State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210093 China Research Center for engineering technology of Organic Poison Control and Resources Reuse in Jiangsu Province Nanjing 210038 China Department of chemical engineering Jiangsu Polytechnic University Changzhou 213016 China

Adsorption behaviors of phenol from aqueous solutions have been investigated in batch systems at 303 K and 318 K respectively, using hypercrosslinked polymeric adsorbent （CHA111）, aminated hypercrosslinked polymeric adsorbents （NDA101, NDA103, NDA105） and weakly basic polymeric adsorbent （D301） with a view to studying the effect of hydrogen bonding and Van der Waals interactions between adsorbate and the adsorbent. All adsorption isotherms can be well fitted by Langmuir and Freundlich equations. Compared with D301 driven by hydrogen bonding interaction only and CHA111 driven by Van der Waals interaction only, phenol adsorption on aminated adsorbents driven by both hydrogen bonding and Van der Waals interactions were apparently different, i.e., negative effect for NDA105, positive effect for NDA101 and synergistic effect for NDA103. In this synergistic action, some weak interactions would contribute more or less to the adsorption than they work individually.

关键词： Polymeric adsorbent Phenol Adsorption behaviours Negative effect Positive effect Synergistic effect.

Distribution and germination of viable diatom resting stage cells in sediments of the East china Sea

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Acta Oceanologica Sinica 2010年第5期29卷 121-128页

作者： ZHANG Yuyu LU Songhui ZHANG Chuansong GAO Yahui Key Laboratory of Ministry of Education for Coast and Wetland Ecosystems School of Life Sciences Xiamen University Xiamen 361005 China Research Center for Harmful Algae and Aquatic environment Jinan University Guangzhou 510632 China College of Life Science South China Normal University Guangzhou 510631 China College of Chemistry and chemical engineering Ocean University of China Qingdao 266100 China

The abundance and temporal patterns of viable diatom resting stage cells in sediments of the East china Sea in 2006 have been *** abundance of viable resting stages was enumerated with the most probable number（MPN） ***,25 diatom species（including varieties） belonging to 16 genera were *** resting stage cells were common,on the order of 103 to 106 cells/g dry *** abundant taxa included Skeletonema marina,***,Chaetoceros curvisetus and Thalassiosira spp.,with Skeletonema accounting for 83.3% of the *** effects of temperature（10,15,20,25 ℃）,salinity（20,25,30,35 psu） and light intensity（0,300,4 000,8 000 lux） on the germination of resting stages in sediment samples were also *** results showed that light intensity had a significant positive effect on the germination of diatom resting stage cells（p 〈0.01） and that diatoms could not germinate in *** and salinity had no noticeable effects on the *** present study suggests that there are abundant diatom resting cells in sediments of the East china Sea,which could serve as a ＂seed bank＂ in the phytoplankton population succession and contribute to the initiation of algal blooms.

关键词： diatom germination MPN resting stages seed bank sediment

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受施工扰动影响土体环境稳定理论与变形控制

同济大学学报（自然科学版） 2004年第10期32卷 1261-1269页

作者：孙钧周健龚晓南张弥同济大学地下建筑与工程系上海200092 浙江大学建筑工程学院浙江杭州310027 北京交通大学土木建筑工程学院北京100044

讨论了城市市区进行的各种工程活动中 ,因施工扰动引起的环境土工损伤问题及其施工变形的智能预测与控制方法 .分别对土体受施工扰动的诸因素 ,如 :对土体力学性态、开挖卸载条件下土体应力路径、土体孔隙比和含水量的变化 ,以及土体结... 详细信息

讨论了城市市区进行的各种工程活动中 ,因施工扰动引起的环境土工损伤问题及其施工变形的智能预测与控制方法 .分别对土体受施工扰动的诸因素 ,如 :对土体力学性态、开挖卸载条件下土体应力路径、土体孔隙比和含水量的变化 ,以及土体结构的破坏、土体化学组成的改变、土体成分的混合与分离和土体固结状态的变化等 ,均作了系统研究 .进而据此从理论上和实验室测试 2方面探讨了就软土工程性质的上述变化对施工过程中土体强度、变形、稳定性和承载力的影响 .另一方面 ,首次将人工智能和自动控制等软科学理论与技术引入岩土工程领域 ,采用了一种称之为“多步滚动预测”的人工神经网络模型于盾构隧道施工中地面沉降的预测和预报 ,还应用了模糊逻辑控制方法对工程施工变形位移实现了实时。

关键词：土体施工扰动环境土工稳定施工变形预测与控制智能方法

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth Sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3,5, SUN Junying4,5, Paul A. Mayewski2 & QIN Dahe5 1. National Climate Center, china Meteorological Administration, beijing 100081, china 2. Climate Change Institute, university of Maine, Orono, ME 04469, USA 3. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, china 4. Chinese Academy of Meteorological Sciences, beijing 100081, china 5. Key Laboratory of Ice Core and Cold Regions environment, Cold and Arid environmental and engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, china National Climate Center China Meteorological Administration Beijing China Climate Change Institute University of Maine Orono ME USA Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Key Laboratory of Ice Core and Cold Regions environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Chinese Academy of Meteorological Sciences Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.