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Flavanoids from Clematis hexapetala 被引量:14
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作者 董彩霞 武可泗 +1 位作者 史社坡 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第1期15-20,共6页
Aim To study the chemical constituents from the roots and rhizomes of Clematis hexapetala Pall.. Methods The components were isolated by means of solvent extraction, repeated chromatography with silica gel, sephadex L... Aim To study the chemical constituents from the roots and rhizomes of Clematis hexapetala Pall.. Methods The components were isolated by means of solvent extraction, repeated chromatography with silica gel, sephadex LH-20 and prep-HPLC. The structures were determined by spectrum analysis. Results Twelve flavonoids were isolated and their structures were identified as 3, 5, 6, 7, 8, 3', 4'-heptamethoxyflavone (1), nobiletin (2), liquiritigenin (3), hesperetin (4), naringenin (5), liquiritigen-7-O-β-D-glucopyranoside (6), 5,7, 4' -trihydroxy-3'- methoxyflavanone -7-O-α-L-rhamnopyranosyl ( 1→6 ) -β-D-glucopyranoside (7), 6-hydroxybiochain A ( 8), formononetin (9), daidzein (10), genistein (11), and tectoridin (12). Conclusion All the said compounds were isolated from the plant for the first time. 展开更多
关键词 Clematis hexapetala Pall. FLAVONOIDS structure determination
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Simulation and Analysis of Land System Structure Changes in Huang-Huai-Hai Plain Area 被引量:6
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作者 邓祥征 战金艳 +2 位作者 苏红波 姜群鸥 迟百余 《Agricultural Science & Technology》 CAS 2007年第3期45-52,共8页
The dynamic changes of land system in Huang - Huai - Hai Plain between 1988 and 2000 were researched in this paper. Spatial dominance econometric model was estabilished on 1 km cell to quantificafionally analyze the d... The dynamic changes of land system in Huang - Huai - Hai Plain between 1988 and 2000 were researched in this paper. Spatial dominance econometric model was estabilished on 1 km cell to quantificafionally analyze the driving-force for the dynamic change mechanism of land system, such as natural, social and economic factors. The future dynamic changes of land system in Huang - Huai - Hai Plain on each 1 km cell during 2000 to 2020 were stimulated by combining the dynamic changes of land system on each 1 km cell with different situations. The research indicated that the dynamic changes of land system structure changed mainly from the cultivated areas to building areas and industrial areas, and forest areas increased during this period. Although the revolutions of land system structure were different during 2000 to 2020 with the different referrence standard, ecological protection and economic development, the primary dynamic changes of land system structure were that the increase of building land areas with the decline cuhivaled land areas and the increase of woodlands. 展开更多
关键词 LAND Land system Land system structure Land system structure change Land use Dynamic simulation Huang- Huai -Hai Plain
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Preliminary Study on Electron Crystallography of 27 kD LHC-Ⅱ Complex from Cucumber
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作者 张旭家 王凌云 +2 位作者 黄有国 王可玢 匡廷云 《Acta Botanica Sinica》 CSCD 2000年第12期1253-1257,共5页
Cucumber ( Cucumis sativus L.) LHC_Ⅱ complex, which consists of only one subunit (27 kD), was isolated and purified. 2_D crystallization was performed by batch method. The crystal is 0.7 μm×1.0 μm, and diff... Cucumber ( Cucumis sativus L.) LHC_Ⅱ complex, which consists of only one subunit (27 kD), was isolated and purified. 2_D crystallization was performed by batch method. The crystal is 0.7 μm×1.0 μm, and diffracts to 30 ?. The projection map of the negatively stained two_dimensional crystal of LHC_Ⅱ complex shows that the crystal has p3 symmetry, lattice constant 15.4 nm×15.4 nm, which is different from the LHC_Ⅱ of spinach (Spinacia oleracea L.) and pea (Pisum satium L.). A continuous tomographic tilt series, containing 12 projections from the two_dimensional crystal was subjected to 3_D reconstruction. The 3_D model represents that LHC_Ⅱ complex consists of 6 monomers. These trimer and dimer interactions build up the six member ring. 展开更多
关键词 LHC_Ⅱ electron microscopy 3_D reconstructio(
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Geological structure of the yellow sea area from regional gravity and magnetic interpretation 被引量:37
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作者 Zhang Minghua Xu Deshu Chen Jianwen 《Applied Geophysics》 SCIE CSCD 2007年第2期75-83,共9页
Regional gravity and aeromagnetic data covering the area of 32°- 38° N, 118°-127° E at the scale of 1:1,000,000 are coordinated and integrated in a synthetic study of the South China Yellow Sea an... Regional gravity and aeromagnetic data covering the area of 32°- 38° N, 118°-127° E at the scale of 1:1,000,000 are coordinated and integrated in a synthetic study of the South China Yellow Sea and adjacent areas. Depth to magnetic crystalline basement and its structure are determined by magnetic anomaly inversion. Depth to and thickness of the Paleozoic rock are also revealed by gravity anomaly inversion with constrains of the basement and known seismic information from several profiles. Structure units, main faults, basin boundaries, and sub-suppressions are outlined on the basis of gravity data interpretation. 展开更多
关键词 Yellow Sea gravity and magnetic interpretation regional structure oil basins.
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Prospective cohort comparison of flavonoid treatment in patients with resected colorectal cancer to prevent recurrence 被引量:12
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作者 Harald Hoensch Bertram Groh +1 位作者 Lutz Edler Wilhelm Kirch 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第14期2187-2193,共7页
AIM: To investigate biological prevention with flavonoids the recurrence risk of neoplasia was studied in patients with resected colorectal cancer and after adenoma polypectomy. METHODS: Eighty-seven patients, 36 pati... AIM: To investigate biological prevention with flavonoids the recurrence risk of neoplasia was studied in patients with resected colorectal cancer and after adenoma polypectomy. METHODS: Eighty-seven patients, 36 patients with resected colon cancer and 51 patients after polypectomy, were divided into 2 groups: one group was treated with a flavonoid mixture (daily standard dose 20 mg apigenin and 20 mg epigallocathechin-gallat, n = 31) and compared with a matched control group (n = 56). Both groups were observed for 3-4 years by surveillance colonoscopy and by questionnaire. RESULTS: Of 87 patients enrolled in this study, 36 had resected colon cancer and 29 of these patients had surveillance colonoscopy. Among the flavonoid-treated patients with resected colon cancer (n = 14), there was no cancer recurrence and one adenoma developed. In contrast the cancer recurrence rate of the 15 matched untreated controls was 20% (3 of 15) and adenomas evolved in 4 of those patients (27%). The combined recurrence rate for neoplasia was 7% (1 of 14) in the treated patients and 47% (7 of 15) in the controls (P = 0.027). CONCLUSION: Sustained long-term treatment with a flavonoid mixture could reduce the recurrence rate of colon neoplasia in patients with resected colon cancer. 展开更多
关键词 FLAVONOIDS Colorectal cancer Recurrence risk Intestinal neoplasia Colon polyps
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Relationships among bioleaching performance, additional elemental sulfur, microbial population dynamics and its energy metabolism in bioleaching of chalcopyrite 被引量:11
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作者 XIA Le-xian TANG Lu +6 位作者 XIA Jin-lan YIN Chu CAI Li-yuan ZHAO Xiao-juan NIE Zhen-yuan LIU Jian-she QIU Guan-zhou 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第1期192-198,共7页
To estimate the relationships among bioleaching performance, additional elemental sulfur (S0), microbial population dynamics and its energy metabolism, bioleaching of chalcopyrite by three typical sulfur- and/or iro... To estimate the relationships among bioleaching performance, additional elemental sulfur (S0), microbial population dynamics and its energy metabolism, bioleaching of chalcopyrite by three typical sulfur- and/or iron-oxidizing bacteria, Acidithiobacillus ferrooxidans, Leptospirillum ferriphilum and Acidithiobacillus thiooxidans with different levels of sulfur were studied in batch shake flask cultures incubated at 30 °C. Copper dissolution capability (71%) was increased with the addition of 3.193 g/L S0, compared to that (67%) without S0. However, lower copper extraction was obtained in bioleaching with excessive sulfur. Microbial population dynamics during chalcopyrite bioleaching process was monitored by using PCR-restriction fragment length polymorphism (PCR-RFLP). Additional S0 accelerated the growth of sulfur-oxidizing bacteria, inhibited the iron-oxidizing metabolism and led to the decrease of iron-oxidizing microorganisms, finally affected iron concentration, redox potential and bioleaching performance. It is suggested that mixed iron and sulfur-oxidizing microorganisms with further optimized additional S0 concentration could improve copper recovery from chalcopyrite. 展开更多
关键词 BIOLEACHING sulfur oxidization iron oxidization microbial community CHALCOPYRITE
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Trophic interactions, ecosystem structure and function in the southern Yellow Sea 被引量:3
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作者 林群 金显仕 张波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期46-58,共13页
The southem Yellow Sea is an important fishing ground, providing abundant fishery resources. However, overfishing and climate change have caused a decline in the resource and damaged the ecosystem. We developed an eco... The southem Yellow Sea is an important fishing ground, providing abundant fishery resources. However, overfishing and climate change have caused a decline in the resource and damaged the ecosystem. We developed an ecosystem model to analyze the trophic interactions and ecosystem structure and function to guide sustainable development of the ecosystem. Atrophic mass-balance model of the southern Yellow Sea during 2000-2001 was constructed using Ecopath with Ecosim software. We defined 22 important functional groups and studied their diet composition. The trophic levels of fish, shrimp, crabs, and cephalopods were between 2.78 and 4.39, and the mean trophic level of the fisheries was 3.24. The trophic flows within the food web occurred primarily in the lower trophic levels. The mean trophic transfer efficiency was 8.1%, of which 7.1% was from primary producers and 9.3% was from detritus within the ecosystem. The transfer efficiency between trophic levels II to III to IV to V to 〉V was 5.0%, 5.7%, 18.5%, and 19.7%-20.4%, respectively. Of the total flow, phytoplankton contributed 61% and detritus contributed 39%. Fishing is defined as a top predator within the ecosystem, and has a negative impact on most commercial species. Moreover, the ecosystem had a high gross efficiency of the fishery and a high value of primary production required to sustain the fishery. Together, our data suggest there is high fishing pressure in the southern Yellow Sea. Based on analysis of Odum's ecological parameters, this ecosystem was at an immature stage. Our results provide some insights into the structure and development of this ecosystem. 展开更多
关键词 ECOPATH trophic interactions ecosystem structure FISHERIES the southern Yellow Sea
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Study on the Activity of Herbal Extract to Kill Root-knot Nematode of Cucumber Seedlings Stage 被引量:4
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作者 张敏 苏康宇 +3 位作者 刘晟 马永清 董书琦 宋吉青 《Agricultural Science & Technology》 CAS 2010年第5期129-133,共5页
Present mature plants hydroponic technology was used,combined with some excellent characteristics,such as growth conditions was easy to control and process of root growth was easy to continuously observe,the nematicid... Present mature plants hydroponic technology was used,combined with some excellent characteristics,such as growth conditions was easy to control and process of root growth was easy to continuously observe,the nematicidal activity of 5 kinds of Chinese herbs extracts and the compound solution of Avermectin,with strong contact toxicity effect indoor,was systematically studied and investigated the affection on the root-knot nematode parasitized on the cucumber seeding stage. It is found that under the premise of no influence on root growth of cucumber,extracts from Picrorhiza scrophulariiflora and Punica granatum showed strong prevention and nematicidal activity,and had the similar efficacy of Avermectin; while the extracts from Cibotium barometz,Aucklandia lappa Decne and Fructus cnidii showed low nematicidal activity and various degrees inhibition effect on plant growth. 展开更多
关键词 Chinese herbal extract Cucumber Hydroponics Root-knot nematode Nemeticidal activity
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Characteristics of discontinuities in Heifangtai landslide area in Gansu,China 被引量:3
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作者 Li Bin Xu Qiang +4 位作者 Cheng Qiang Liu Tian-Xiang Tang Ming-Gao Zheng Guang Wang Hai-Yan 《Applied Geophysics》 SCIE CSCD 2020年第5期857-869,904,905,共15页
Loesses are widely distributed all over the world,especially in China.Meanwhile,long-term agricultural irrigation and extreme climate changes have led to frequent geological disasters in the Heifangtai area of Lanzhou... Loesses are widely distributed all over the world,especially in China.Meanwhile,long-term agricultural irrigation and extreme climate changes have led to frequent geological disasters in the Heifangtai area of Lanzhou,Gansu,China.Of these,landslides are one of the most frequent types of disasters that are harmful to humans and the environment.A landslide is closely related to the lithology,structure,and groundwater of the site and consists of a combination of structure units divided by discontinuities,such as faults,joints,and fi ssures.Therefore,geological surveys,engineering drilling,and trenching are typically used to identify the stratum lithology,structure,and groundwater in order to visually display underground information within a limited depth range.However,these methods have disadvantages.In particular,geological surveys can only describe geological phenomena on the surface,while the cost of drilling and trenching may be high,along with the ineffi ciency of exploration.In this research,the integrated geophysical exploration method was used to analyze the hidden joints,cracks,and other discontinuities and geophysical features of the discontinuities.The results were verified by trench exploration,and large amounts of underground information were obtained,especially the spread and distribution of discontinuities in landslide areas.Such information can be effectively used for carrying out and providing meaningful experiences and lessons in future comprehensive geophysical processing and interpretations related to the prediction and evaluation of landslides. 展开更多
关键词 LOESS LANDSLIDE DISCONTINUITIES GEOPHYSICS engineering geology
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Facile synthesis of UCNPs/Zn_xCd_(1-x)S nanocomposites excited by near-infrared light for photochemical reduction and removal of Cr(Ⅵ) 被引量:7
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作者 Mengli Zhao Wanni Wang +5 位作者 Chenxi Huang Wang Dong Yang Wang Sheng Cheng Huiqing Wang Haisheng Qian 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第7期1240-1248,共9页
Photocatalysis driven by near-infrared(NIR)light is of scientific and technological interest for ex-ploiting solar energy.In this study,we demonstrate a facile hydrothermal process to synthesize core-shell nanoparti... Photocatalysis driven by near-infrared(NIR)light is of scientific and technological interest for ex-ploiting solar energy.In this study,we demonstrate a facile hydrothermal process to synthesize core-shell nanoparticles combining upconversion nanoparticles(UCNPs)and alloyed ZnxCwhich can be excited using NIR or visible light.Morphologies,phase,and chemical composition have been investigated using field-emission scanning electron microscopy,transmission electron mi-croscopy,X-ray diffraction analysis,and atomic absorption spectroscopy.Moreover,we found that amorphous TiO2 layers existing in the final samples play an important role in formation ofyolk-shell nanoparticles,which bind the as-prepared ZnxCnanoparticlescan be tuna-ble by adjusting the amount of the Cd and Zn source compounds.The photochemical reduction of Cr(Ⅵ)in water has been performed to study the photocatalytic performance under irradiation by NIR light or a simulated solar light,showing efficient photoreduction and Cr(Ⅵ)removal over the/TiO2 yolk-shell nanoparticles.The as-prepared UCNPs@ZnxC/TiO2 nanoparticles show excellent production of hydroxyl radicals,which are responsible for the photochemical reduction of Cr(Ⅵ)to Cr(Ⅲ).This study will provide an alternative strategy for en-vironmental wastewater treatment,making full use of solar energy. 展开更多
关键词 Upconversion nanoparticle ZnxCd1-xS alloyed semiconductor Yolk-shell PHOTOCATALYSIS Hydrothermal synthesis
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Bioleaching of chalcopyrite with different crystal phases by Acidianus manzaensis 被引量:7
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作者 Zhen-yuan NIE Wei-wei ZHANG +6 位作者 Hong-chang LIU Hong-rui ZHU Chang-hui ZHAO Duo-rui ZHANG Wei ZHU Chen-yan MA Jin-lan XIA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第3期617-624,共8页
Bioleaching of chalcopyrite with different crystal structures (α-phase,β-phase and γ-phase) by Acidianus manzaensis was comparatively studied by synchrotron radiation based X-ray diffraction (SR-XRD) and S K-edge X... Bioleaching of chalcopyrite with different crystal structures (α-phase,β-phase and γ-phase) by Acidianus manzaensis was comparatively studied by synchrotron radiation based X-ray diffraction (SR-XRD) and S K-edge X-ray absorption near edge structure (XANES) spectroscopy. The α-phase,β-phase and γ-phase chalcopyrite was prepared by heating original chalcopyrite at 583, 773 and 848 K, respectively. Bioleaching results showed that [Cu^2+] in the leaching solution of α-phase,β-phase,γ-phase and original chalcopyrite after 10 days of bioleaching was 1.27, 1.86, 1.43 and 1.13 g/L, respectively, suggesting that β-phase had a better leaching kinetics than others. SR-XRD and XANES results indicated that jarosite and chalcopyrite were the main components in the leaching residues in all cases, and elemental sulfur formed in the early stage of bioleaching. While for β-phase and γ-phase chalcopyrite during bioleaching, bornite was produced in the initial stage of leaching, and turned into chalcocite on day 6. 展开更多
关键词 CHALCOPYRITE crystal structure BIOLEACHING Acidianus manzaensis SR-XRD XANES
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Calculation of electron structure by density function theory and electrochemical process of surface (100) of FeS_2 被引量:9
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作者 黎全 覃文庆 +1 位作者 孙伟 邱冠周 《Journal of Central South University of Technology》 EI 2007年第5期618-622,共5页
The electron structure of FeS2 surface (100) was computed by DFT (density function theory) and the process of electron transfer in sulfide flotation was simulated through ab-initio calculation. The results show th... The electron structure of FeS2 surface (100) was computed by DFT (density function theory) and the process of electron transfer in sulfide flotation was simulated through ab-initio calculation. The results show that the interaction between xanthate and FeS2 is controlled by the energy of valence band. The products and degree of the reaction depend on the density of state of valence band and concentration election structure on the surface of of positive hole in valence band. Interaction between xanthate and pyrite can be changed by modifying the of the surface of pyrite. Xanthate is adsorbed on the surface of intrinsic pyrite. But the amount of xanthate adsorbed the pyrite with sulfur vacancy is more than that on the surface of the intrinsic pyrite due to the higher electron and vacancy density. Xanthate is not adsorbed on the surface of pyrite with Fe vacancy because of its high Fermi energy 展开更多
关键词 PYRITE electrochemiscal process FLOTATION ab-initio calculation
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Effect of TYLCV Infection on Leaf Anatomical Structure and Protective Enzyme System of Tomato 被引量:7
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作者 张永平 张辉 +1 位作者 朱龙英 朱为民 《Agricultural Science & Technology》 CAS 2009年第4期150-153,共4页
[Objective] The aim was to study the effect of tomato yellow leaf curl virus (TYLCV) infection on leaf anatomical structure and protective enzyme system of tomato. [Method] The anatomical structure of infected and h... [Objective] The aim was to study the effect of tomato yellow leaf curl virus (TYLCV) infection on leaf anatomical structure and protective enzyme system of tomato. [Method] The anatomical structure of infected and healthy leaves of tomato were observed and compared by using paraffin section method. The activity changes of SOD, POD and CAT in the infected leaves of tomato were determined. [ Result] The results revealed that there were some differences in anatomical structure between healthy and infected leaves. Some cells of infected leaves were damaged so that the leaves curled and became yellow, which affected the normal function of organs. Compared with control, enzyme activities in the tomato plants infected by TYLCV were enhanced at the early periods and higher than that in control, then started to decline at the middle and late periods but lower than that in control.[ Conclusion] After infection by TYLCV, the leaf anatomical structure of tomato was changed greatly and the protective enzyme system was damaged severely, and affected the normal physJological metabolic functions of tissues and organs in tomato in further. 展开更多
关键词 TYLCV INFECTION Anatomical structure Protective enzyme system
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The Structure and Formation Mechanism of a Sea Fog Event over the Yellow Sea 被引量:5
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作者 GUO Jingtian LI Pengyuan +3 位作者 FU Gang ZHANG Wei GAO Shanhong ZHANG Suping 《Journal of Ocean University of China》 SCIE CAS 2015年第1期27-37,共11页
In this paper, a heavy sea fog event occurring over the Yellow Sea on 11 April 2004 was investigated based upon observational and modeling analyses. From the observational analyses, this sea fog event is a typical adv... In this paper, a heavy sea fog event occurring over the Yellow Sea on 11 April 2004 was investigated based upon observational and modeling analyses. From the observational analyses, this sea fog event is a typical advection cooling case. Sea surface temperature(SST) and specific humidity(SH) show strong gradients from south to north, in which warm water is located in the south and consequently, moisture is larger in the south than in the north due to evaporation processes. After fog formation, evaporation process provides more moisture into the air and further contributes to fog evolution. The sea fog event was reproduced by the Regional Atmospheric Modeling System(RAMS) reasonably. The roles of important physical processes such as radiation, turbulence as well as atmospheric stratification in sea fog's structure and its formation mechanisms were analyzed using the model results. The roles of long wave radiation cooling, turbulence as well as atmospheric stratification were analyzed based on the modeling results. It is found that the long wave radiative cooling at the fog top plays an important role in cooling down the fog layer through turbulence mixing. The fog top cooling can overpower warming from the surface. Sea fog develops upward with the aid of turbulence. The buoyancy term, i.e., the unstable layer, contributes to the generation of TKE in the fog region. However, the temperature inversion layer prevents fog from growing upward. 展开更多
关键词 sea fog the Yellow Sea developing mechanism
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Effects of phosphorus and potassium addition on growth and nodulation of Dalbergia sissoo in the nursery 被引量:2
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作者 S. M. S. Huda M. Sujauddin +1 位作者 S. Shafinat M. S. Uddin 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期279-282,共4页
A study was conducted to test the influence of different inorganic fertilizers (phosphorous and potassium) on the nodulation and growth of Dalbergia sissoo grown in the nursery. Before seeds sowing, different combin... A study was conducted to test the influence of different inorganic fertilizers (phosphorous and potassium) on the nodulation and growth of Dalbergia sissoo grown in the nursery. Before seeds sowing, different combinations of P, K fertilizers were incorporated with the nutrient-deficient natural forest soils, and then amended with cowdung (soil: cowdung = 3:1). Nodulation status (nodule number, shape, fresh weight, dry weight and color) in the roots and the plant growth parameters (length of shoot and root, collar diameter, fresh and dry weight of shoot and root) were recorded 60 days after seeds sowing. Nodulation status and growth of the plants varied significantly (P〈0.05) in the soils amended with fertilizers in comparison to the control. The highest nodule number (62), fresh (0.50 g) and dry (0.07 g) weights were recorded with the dose of PK at the rate of 160 kg/hm2. Nodule shape and color also varied widely in different treatments. In case of plant growth parameters, shoot and root length, collar diameter, fresh and dry weight of the plants took on a significant difference (P〈0.05) among various combination of fertilizers. From the study, it is revealed that PK at the rate of 160 kg/hm^2 fertilizer with soil and cowdung mixture (soil: eowdung = 3:1) is recommended for optimum growth and nodule formation of D. sissoo in degraded soils at a nursery level. 展开更多
关键词 Dalbergia sissoo Inorganic fertilizers NODULATION Seedling growth NURSERY
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Molecular structures and activity of organic depressants for marmatite,jamesonite and pyrite flotation 被引量:12
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作者 陈建华 李玉琼 龙秋容 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期1993-1999,共7页
Ten kinds of organic depressants were used to investigate the depressing performance on marmatite and pyrite.Flotation results show that the organic compounds only with single group of hydroxyl(-OH),carboxyl(-COOH) or... Ten kinds of organic depressants were used to investigate the depressing performance on marmatite and pyrite.Flotation results show that the organic compounds only with single group of hydroxyl(-OH),carboxyl(-COOH) or amino(-NH2) in molecule are ineffective in depressing marmatite,jamesonite and pyrite.The combinations of these functional groups still cannot enhance the depressing ability of organic depressant.The thioglycollic acid containing reductive functional group(-SH) has a good depressing performance for marmatite and pyrite.The presence of benzene ring in molecule can enhance the depressing performance.The functional group electronegativity,hydrophilic-hydrophobic indexes and frontier orbital of organic depressants were calculated,and the criterion for the depressing effect of organic depressants to sulphide minerals was proposed. 展开更多
关键词 MARMATITE PYRITE organic depressant frontier orbital
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Prevention of hepatotoxicity due to anti tuberculosis treatment: A novel integrative approach 被引量:13
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作者 Meghna R Adhvaryu Narsimha M Reddy Bhasker C Vakharia 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第30期4753-4762,共10页
AIM: To evaluate the ability of Curcuma Ionga (CL) and Tinospora cordifolia (TC) formulation to prevent anti-tuberculosis (TB) treatment (ATT) induced hepatotoxicity. METHODS: Patients with active TB diagnos... AIM: To evaluate the ability of Curcuma Ionga (CL) and Tinospora cordifolia (TC) formulation to prevent anti-tuberculosis (TB) treatment (ATT) induced hepatotoxicity. METHODS: Patients with active TB diagnosis were randomized to a drug control group and a trial group on drugs plus an herbal formulation. Isoniazid, rifampicin, pyrazinamide and ethambutol for first 2 mo followed by continuation phase therapy excluding Pyrazinamide for 4 mo comprised the anti-tuberculous treatment. Curcumin enriched (25%) CL and a hydro-ethanolic extract enriched (50%) TC 1 g each divided in two doses comprised the herbal adjuvant. Hemogram, bilirubin and liver enzymes were tested initially and monthly till the end of study to evaluate the result. RESULTS: Incidence and severity of hepatotoxicity was significantly lower in trial group (incidence: 27/192 vs 2/316, P 〈 0.0001). Mean aspartate transaminase (AST) (195.93 ± 108.74 vs 85 ± 4.24, P 〈 0.0001), alanine transaminase (ALT) (75.74 ± 26.54 vs 41 ± 1.41, P 〈 0.0001) and serum bilirubin (5.4 ±3.38 vs 1.5 ±0.42, P 〈 0.0001). A lesser sputum positivity ratio at the end of 4 wk (10/67 vs 4/137, P = 0.0068) and decreased incidence of poorly resolved parenchymal lesion at the end of the treatment (9/152 vs 2/278, P = 0.0037) was observed. Improved patient compliance was indicated by nil drop-out in trial vs 10/192 in control group (P 〈 0.0001). CONCLUSION: The herbal formulation prevented hepatotoxicity significantly and improved the disease outcome as well as patient compliance without any toxicity or side effects. 展开更多
关键词 HEPATOPROTECTION Anti-tuberculous treatment Curcumin Ionga Tinospora cordifolia
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Advanced yolk-shell nanoparticles as nanoreactors for energy conversion 被引量:3
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作者 Meiwen Wang Yash Boyjoo +2 位作者 Jian Pan Shaobin Wang Jian Liu 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第6期970-990,共21页
Yolk‐shell structured nanoparticles are of immense scientific and technological interests because of their unique architecture and myriad of applications.This review summarizes recent progresses in the use of yolk‐s... Yolk‐shell structured nanoparticles are of immense scientific and technological interests because of their unique architecture and myriad of applications.This review summarizes recent progresses in the use of yolk‐shell structured nanoparticles as nanoreactors for various chemical reactions.A very brief overview of synthetic strategies is provided with emphasis on recent research progress in the last five years.Catalytic applications of these yolk‐shell structured nanoreactors are then discussed by covering photocatalysis,methane reforming and electrochemical conversion.The state of the art research and perspective in future development are also highlighted. 展开更多
关键词 Yolk‐shell nanoreactors Energy conversion applications PHOTOCATALYSIS Fuel cell Utilization of carbon sources
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Biomarker Records of Phytoplankton Productivity and Community Structure Changes in the Central Yellow Sea Mud Area During the Mid-Late Holocene 被引量:12
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作者 ZHAO Xiaochen TAO Shuqin +3 位作者 ZHANG Rongping ZHANG Hailong YANG Zuosheng ZHAO Meixun 《Journal of Ocean University of China》 SCIE CAS 2013年第4期639-646,共8页
The Yellow Sea (YS) environmental and ecological changes during the Holocene are driven by the interactions between the Yellow Sea Warm Current (YSWC), the East Asian Winter Monsoon (EAWM) and the Kuroshio Curre... The Yellow Sea (YS) environmental and ecological changes during the Holocene are driven by the interactions between the Yellow Sea Warm Current (YSWC), the East Asian Winter Monsoon (EAWM) and the Kuroshio Current (KC). We report marine biomarker records of brassicasterol, dinosterol and C37 alkenones in core ZY1 and core ZY2 from the South Yellow Sea (SYS) to reconstruct the spatial/temporal variations and possible mechanisms of phytoplankton primary productivity and community structure changes during the Mid-late Holocene. The contents of the corresponding biomarkers in the two cores are similar, and they also reveal broadly similar temporal trends. From 6kyr to 3kyr, the biomarker contents in the two cores were relatively low with small oscillations, followed by a distinct increase at about 3 kyr indicating productivity increases caused by a stronger EAWM. The alkenone/brassicasterol ratio (A/B) is used as a community structure proxy, which also showed higher values in both cores since 3 kyr, indicating increased haptophyte contribution to total productivity. It is proposed that the YS community structure has been mainly influenced by the YSWC, with stronger YSWC influences causing an increase in haptophyte contribution since 3 kyr. Some differences of the biomarker records between ZY2 and ZYI suggest spatial variations in response to YSWC and KC forcing. When the KC was intensified during the periods of 6-4.2kyr and 1.7-0kyr, the YSWC extended eastward, exerting more influence on core ZY1. On the other hand, when the KC weakened during 4.2-1.7 kyr, the YSWC extended westward, exerting more influence on the ZY2. 展开更多
关键词 BIOMARKER South Yellow Sea PRODUCTIVITY community structure Yellow Sea Warm Current East Asian Winter Monsoon Kuroshio Current
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Petroleum geological framework and hydrocarbon potential in the Yellow Sea 被引量:3
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作者 吴时国 倪祥龙 蔡峰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第1期23-34,共12页
Sedimentary basins in the Yellow Sea can be grouped tectonically into the North Yellow Sea Basin (NYSB), the northern basin of the South Yellow Sea (SYSNB) and the southern basin of the South Yellow Sea (SYSSB). The N... Sedimentary basins in the Yellow Sea can be grouped tectonically into the North Yellow Sea Basin (NYSB), the northern basin of the South Yellow Sea (SYSNB) and the southern basin of the South Yellow Sea (SYSSB). The NYSB is connected to Anju Basin to the east. The SYSSB extends to Subei Basin to the west. The acoustic basement of basins in the North Yellow Sea and South Yellow Sea is disparate, having different stratigraphic evolution and oil accumulation features, even though they have been under the same stress regime since the Late Triassic. The acoustic basement of the NYSB features China-Korea Platform crystalline rocks, whereas those in the SYSNB and SYSSB are of the Paleozoic Yangtze Platform sedimentary layers or metamorphic rocks. Since the Late Mesozoic terrestrial strata in the eastern of the NYSB (West Korea Bay Basin) were discovered having industrial hydrocarbon accumulation, the oil potential in the Mesozoic strata in the west depression of the basin could be promising, although the petroleum exploration in the South Yellow Sea has made no break-through yet. New deep reflection data and several drilling wells have indicated the source rock of the Mesozoic in the basins of South Yellow Sea, and the Paleozoic platform marine facies in the SYSSB and Central Rise could be the other hosts of oil or natural gas. The Mesozoic hydrocarbon could be found in the Mesozoic of the foredeep basin in the SYSNB that bears potential hydrocarbon in thick Cretaceous strata, and so does the SYSSB where the same petroleum system exists to that of oil-bearing Subei Basin. 展开更多
关键词 sedimentary basin petroleum system hydrocarbon potential the Yellow Sea
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