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Potential sources of unintentionally produced PCB, HCB, and PeCBz in China: A preliminary overview

Xiaotu Liu, Heidelore Fiedler, Wenwen Gong, Bin Wang, Gang Yu

《环境科学与工程前沿（英文）》 2018年第12卷第6期 doi: 10.1007/s11783-018-1036-9

摘要：

A preliminary analysis of potential sources for unintentionally produced PCB, HCB and PeCBz in China.

Activity rates of sources for reference years from 2000 to 2015 provided.

Emissions from a number of sources summarized and compared.

Implications for future research and regulation discussed.

关键词： Unintentionally produced POPs Polychlorinated biphenyls Hexachlorobenzene Pentachlorobenzene sources of releases Annual production activities

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兴建年产一千吨电子级多晶硅工厂的思考

梁骏吾

《中国工程科学》 2000年第2卷第6期页码 33-35

摘要：

文章简要评述了世界以及中国的电子级多晶硅的生产能力和市场需求。在2000年和2010年中国对多晶硅的需求分别是736 t/a和1304 t/a。但近几年中国的多晶硅生产仅达到80 t/a，所以在中国建设一座年产1000 t电子级多晶硅的工厂是很合理的。然而由最新统计数据可知，自1997年以来，世界多晶硅生产能力连年均超过市场需求，而且在最近的将来，这一趋势将会继续。为了占领国内多晶硅市场，未来的多晶硅工厂将面临挑战，产品质量和生产成本是应当考虑的最重要指标。为了占领国内市场，在保证多晶硅产品纯度的前提下，生产成本只能略微超过20美元/kg。

关键词：多晶硅半导体工业规模生产

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Estrogenic activities of di-2-ethylhexyl phthalate

JIN Qiumei, LI Yan, SUN Zengrong

《医学前沿（英文）》 2008年第2卷第3期页码 303-308 doi: 10.1007/s11684-008-0058-2

摘要： Phthalate esters are widespread in the environment. They have been described as being one of the most abundant man-made environmental contaminants that may be adverse to human health. Particularly, di-2-ethylhexyl phthalate (DEHP) has been shown to cause reproductive and developmental toxicity and is suspected to be an endocrine disruptor. The primary objective of this study is to determine the estrogenic activity of DEHP. Estrogenic activities of DEHP were studied by assays of human breast cancer MCF-7 cell proliferation. Estrogen-dependent MCF-7 cells were grown in RPMI1640 medium containing 10% fetal bovine serum. Five days before the addition of the test compounds, the cells were washed by phosphate balanced solution (PBS), and the medium was substituted with a phenol red-free RPMI1640 medium containing 5% dextral charcoal-stripped Fetal Bovine Serum (FBS). Fresh medium was added to the respective test compounds and the control cell received only the vehicle (ethanol). The proliferation of MCF-7 cell was analyzed by the MTT assay, growth curves, mitotic index and colony forming efficiency. Compared with the ethanol control cells, the proliferation of tested cells treated with DEHP, like estradiol, was significantly enhanced and the activity of the cell proliferation reached the maximum at 1 × 10 mol/L DEHP. The relative proliferative potency of DEHP was 0.000 001 with a relative proliferative effect of 97.32%. During the log phase, the mitotic index of the tested cells treated with DEHP and estradiol was significantly increased. The cell cloning efficiency was enhanced, which was treated by 10 mol/L DEHP only for 48 hours. The results show a time-dependent and dose-dependent model. Di-2-ethylhexyl phthalate enhanced the proliferation of human breast cancer MCF-7 cells and might demonstrate an estrogenic activity.

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Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

《化学科学与工程前沿（英文）》 2022年第16卷第7期页码 1090-1100 doi: 10.1007/s11705-021-2091-5

摘要： Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by ¹H nuclear magnetic resonance (NMR), ¹³C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.

关键词： synthesis pyrimidin-4-amine derivatives 1 2 4-oxadiazole insecticidal activity structure-activity relationship

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我国航天的成就与发展

王礼恒

《中国工程科学》 2008年第10卷第12期页码 10-12

摘要：

概述了国际航天发展的现状，对国际航天发展的新趋向“新世纪航天新计划”及其特点进行了概括，同时客观地总结了我国航天事业发展所取得的辉煌成就，在此基础上充分地展望了我国航天事业未来的发展愿景。

关键词：中国航天航天新计划中国航天成就

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A comparison of the biological activities of ethyl acetate fractions from the stems and leaves of

Zhaolei WANG, Kai JIANG, Qinchao DING, Shujun LIU, Xiaobing DOU, Bin DING

《农业科学与工程前沿（英文）》 2020年第7卷第4期页码 505-512 doi: 10.15302/J-FASE-2019271

摘要：

Pursh (PCP) is a popular traditional medicinal plant in China, widely used for the treatment of a variety of liver diseases. Although it has been long recognized that the main active elements of PCP are contained in ethyl acetate fraction (EAF), little is known so far in terms of the relative effectiveness of EAF derived from the stems versus leaves of this plant. In the current study, we prepared EAF by reflux extraction and sequential extraction from the stems (SEAF) and leaves (LEAF) of PCP and tested their hepatoprotective efficacies. The extract rates and flavonoid contents of LEAF were higher than those of SEAF. EAFs (>50 μg·mL ) prevented lipid accumulation in cells and protected against lipotoxicity injury when the concentration exceeded 25 μg·mL . More than 95% free radicals released by 2,2-diphenyl-1-picrylhydrazyl (DPPH) were eliminated by 25 μg·mL SEAF and 50 μg·mL LEAF, respectively. Further, EAFs (25 μg·mL ) also showed protective antioxidant effects, with the activity of LEAF being significantly higher than that of SEAF. EAFs (10 mg·mL ) also showed similar unspecific bacteriostatic activity. In comparison with SEAF, LEAF contained more flavonoids and had a higher anti-oxidation capability and for these reasons we suggest it should be better for clinical use.

关键词： antibacterial anti-oxidation lipid accumulation lipotoxicity Penthorum chinense Pursh

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Corrigendum to “Multidecadal Trends in Large-Scale Annual Mean SATa Based on CMIP5 Historical Simulations Corrigendum

Nan Xing,Jianping Li,Lanning Wang

《工程（英文）》 2017年第3卷第3期页码 428-428 doi: 10.1016/J.ENG.2017.03.015

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试论人类水事活动的新思维

李佩成

《中国工程科学》 2000年第2卷第2期页码 5-9

摘要：

总结过去，展望未来，作者提出新世纪人类水事活动的新思维，并用大量事例和数据作了论证，认为在21世纪的水事活动中必须正确处理人类活动、水体动态、生态环境、经济发展与社会进步的关系，简称人-水-环-发-社关系；要特别把握人类水事活动和其它人类活动对水体动态的长期影响及其逆反作用；要把水库视为保护和恢复水源的决定性措施加以实现；正确处理耕地、绿地和水域的关系，保护并适当增大水体面积，保护沼泽，关心小河小水的命运；在未来水事活动中要从与天的抗争转变为适应与利用，充分运用各种信息技术建立“信息水利”，并通过对水文气象的把握，经营“应变农业”，从而在获得足够农产品的同时能在用水量最大的部门求得战略性的节水途径。

关键词：水事活动节水水保护新思维

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中国航天的发展战略和重点领域

孙来燕

《中国工程科学》 2006年第8卷第10期页码 6-12

摘要：

回顾了中国航天50年来取得的成就，总结了中国航天发展的经验及存在的差距；就国际航天的发展趋势，阐述了我国航天未来的发展战略及重点发展领域。

关键词：中国航天发展战略重点领域

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Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

《环境科学与工程前沿（英文）》 2008年第2卷第2期页码 218-223 doi: 10.1007/s11783-008-0037-5

摘要： To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated. Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase were determined by potassium permanganate titration, TTC (CHN·Cl) colorimetry, phenyl phosphate dinatrium colorimetry, and anthrone colorimetry, respectively. The result showed that soil pH, organic carbon (C), and total nitrogen (N) had great effects on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 0–20 cm thick soil. However, pH only had great effect on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 20–40 cm thick soil. Hydrogen peroxidase, dehydrogenase, and alkaline phosphatase were important biological indicators for the fertility of urban forest soil. Both in 0–20 cm and 20–40 cm soil, soil enzyme system (hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase) had a close relationship with a combination of physicochemical indicators (pH, organic C, total N, available K, available P, cation exchange capacity (CEC), and microbial biomass carbon (C)). The more soil enzyme activities there were, the higher the fertility of urban forest soil.

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Beneficial metabolic activities of inflammatory cytokine interleukin 15 in obesity and type 2 diabetes

null

《医学前沿（英文）》 2015年第9卷第2期页码 139-145 doi: 10.1007/s11684-015-0377-z

摘要：

In obesity, chronic inflammation is believed to induce insulin resistance and impairs adipose tissue function. Although this view is supported by a large body of literature, it has been challenged by growing evidence that pro-inflammatory cytokines may favor insulin sensitivity through induction of energy expenditure. In this review article, interleukin 15 (IL-15) is used as a new example to explain the beneficial effects of the pro-inflammatory cytokines. IL-15 is secreted by multiple types of cells including macrophages, neutrophils and skeletal muscle cells. IL-15 expression is induced in immune cells by endotoxin and in muscle cells by physical exercise. Its transcription is induced by transcription factor NF-κB. IL-15 binds to its receptor that contains three different subunits (α, β and γ) to activate JAK/STAT, PI3K/Akt, IKK/NF-κB and JNK/AP1 pathways in cells. In the regulation of metabolism, IL-15 reduces weight gain without inhibiting food intake in rodents. IL-15 suppresses lipogenesis, stimulates brown fat function, improves insulin sensitivity through weight loss and energy expenditure. In human, circulating IL-15 is negatively associated with body weight. In the immune system, IL-15 stimulates proliferation and differentiation of T cells, NK cells, monocytes and neutrophils. In the anti-obesity effects of IL-15, T cells and NK cells are not required, but leptin receptor is required. In summary, evidence from human and rodents supports that the pro-inflammatory cytokine IL-15 may enhance energy expenditure to protect the body from obesity and type 2 diabetes. The mechanism of IL-15 action remains to be fully uncovered in the regulation of energy expenditure.

关键词： inflammation obesity cytokine energy expenditure insulin resistance

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Antioxidant and antitumor effects and immunomodulatory activities of crude and purified polyphenol extract

Xiaohong Kou,Lihua Han,Xingyuan Li,Zhaohui Xue,Fengjuan Zhou

《化学科学与工程前沿（英文）》 2016年第10卷第1期页码 108-119 doi: 10.1007/s11705-016-1553-7

摘要： The antioxidant and antitumor effects as well as the immunomodulatory activities of crude and purified polyphenol extract from blueberries were investigated. The antioxidant and antitumor effects of the polyphenol extract were measured both and , and their effect on the immune systems of CD-1 tumor-bearing mice were also analyzed. assays demonstrated that blueberry purified polyphenol extract (BBPP) exhibited higher antioxidant activities than blueberry crude polyphenol extract (BBCP), but the opposite effect was observed . Both the and antitumor activity and the immunity assay showed that BBCP not only inhibited tumor growth, but also significantly improved the immunity of the mice. According to physical and histological studies, the CD-1 tumor-bearing mice treated with the polyphenol extract, especially high doses of BBCP experienced a higher quality of life than the positive control group (treated with cyclophosphamide). These results indicate that BBCP has significant antioxidant and antitumor activities and that it can enhance the immunity of CD-1 tumor-bearing mice.

关键词： crude polyphenol extract purified polyphenol extract blueberry antioxidant antitumor immunity

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and mechanism insight on SiC quantum dots sensitized inverse opal TiO with superior photocatalytic activities

《化学科学与工程前沿（英文）》 2023年第17卷第12期页码 1913-1924 doi: 10.1007/s11705-023-2350-8

摘要： The combination of SiC quantum dots sensitized inverse opal TiO₂ photocatalyst is designed in this work and then applied in wastewater purification under simulated sunlight. From various spectroscopic techniques, it is found that electrons transfer directionally from SiC quantum dots to inverse opal TiO₂, and the energy difference between their conduction/valence bands can reduce the recombination rate of photogenerated carriers and provide a pathway with low interfacial resistance for charge transfer inside the composite. As a result, a typical type-II mechanism is proved to dominate the photoinduced charge transfer process. Meanwhile, the composite achieves excellent photocatalytic performances (the highest apparent kinetic constant of 0.037 min^–1), which is 6.2 times (0.006 min^–1) and 2.1 times (0.018 min^–1) of the bare inverse opal TiO₂ and commercial P25 photocatalysts. Therefore, the stability and non-toxicity of SiC quantum dots sensitized inverse opal TiO₂ composite enables it with great potential in practical photocatalytic applications.

关键词： inverse opal TiO₂ silicon carbide quantum dots quantum dot sensitized photocatalyst type-II charge transfer route

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Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

《环境科学与工程前沿（英文）》 2013年第7卷第1期页码 43-48 doi: 10.1007/s11783-012-0397-8

摘要： The effects of hydraulic retention time (HRT) on the nitrification activities and population dynamics of a conventional activated sludge system fed with synthetic inorganic wastewater were investigated over a period of 260 days. When the HRT was gradually decreased from 30 to 5 h, the specific ammonium-oxidizing rates (SAOR) varied between 0.32 and 0.45 kg (kg mixed liquor suspended solids (MLSS)·d) , and the specific nitrate-forming rates (SNFR) increased from 0.11 to 0.50 kg (kg MLSS·d) , showing that the decrease in HRT led to a significant increase in the nitrite oxidation activity. According to fluorescence in situ hybridization (FISH) analysis results, the proportion of ammonia-oxidizing bacteria (AOBs) among the total bacteria decreased from 33% to 15% with the decrease in HRT, whereas the fraction of nitrite-oxidizing bacteria (NOBs), particularly the fast-growing sp., increased significantly (from 4% to 15% for NOBs and from 1.5% to 10.6% for sp.) with the decrease in HRT, which was in accordance with the changes in SNFR. A short HRT favored the relative growth of NOBs, particularly the fast-growing sp., in the conventional activated sludge system.

关键词： ammonia-oxidizing bacteria hydraulic retention time nitrification activity nitrite-oxidizing bacteria population dynamics

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Catalytic activities and mechanism of formaldehyde oxidation over gold supported on MnO

Guanglong PANG,Donghui WANG,Yunhong ZHANG,Chunyan MA,Zhengping HAO

《环境科学与工程前沿（英文）》 2016年第10卷第3期页码 447-457 doi: 10.1007/s11783-015-0808-8

摘要： MnO microspheres with various surface structures were prepared using the hydrothermal method, and Au/MnO catalysts were synthesized using the sol-gel method. We obtained three MnO microspheres and Au/MnO samples: coherent solid spheres covered with wire-like nanostructures, solid spheres with nanosheets, and hierarchical hollow microspheres with nanoplatelets and nanorods. We investigated the properties and catalytic activities of formaldehyde oxidation at room temperature. Crystalline structures of MnO are the main factor affecting the catalytic activities of these samples, and γ-MnO shows high catalytic performance. The excellent redox properties are responsible for the catalytic ability of γ-MnO . The gold-supported interaction can change the redox properties of catalysts and accelerate surface oxygen species transition, which can account for the catalytic activity enhancement of Au/MnO . We also studied intermediate species. The dioxymethylene (DOM) and formate species formed on the catalyst surface were considered intermediates, and were ultimately transformed into hydrocarbonate and carbonate and then decomposed into CO . A proposed mechanism of formaldehyde oxidation over Au/MnO catalysts was also obtained.

关键词： MnO₂ microspheres Au/MnO₂ formaldehyde oxidation γ-MnO₂