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Effects of mercury contaminated rice from typical chemical plant area in China on nitric oxide changes and c-fos expression of rats brain 被引量:8
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作者 CHENGJin-ping WANGWen-hua +3 位作者 JIAJin-ping HUWei-xuan SHIWei LinXue-yu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期177-180,共4页
China is one of countries with the highest mercury production in the world. The Guizhou Province in Southwestern China is currently one of the world's most important mercury production areas. In order to study the... China is one of countries with the highest mercury production in the world. The Guizhou Province in Southwestern China is currently one of the world's most important mercury production areas. In order to study the neurotoxicity of rice from Qingzhen Chemical Plant area and probe into the signal transduction molecular mechanism of injury in rat brain stimulation by mercury contaminated rice. The rats were exposed to mercury contaminated rice for 20 d. Both of the measurements of NO and NOS were processed according to the protocol of the kit. The effect of Hg contaminated rice on the expression of c-fos mRNA in rat brain and the expression of c-FOS protein in cortex, hippocampus were observed using reverse transcription polymerase chain reaction(RT-PCR) and immunocytochemical methods. The results showed the neural transmitter NO and NOS in brain were significantly change between exposure groups and control group; the mercury polluted rice induced significantly the expression of c-fos mRNA; the c-FOS positive cells in hippocampus and cortex of exposure groups were significant different from control group(p<0.01). It could be concluded that nitric oxide was involved in mercury contaminated rice induced immediate early gene c-fos expressions in the rat brain. Through food chain, local ecosystem and health of local people iave been deteriorated seriously by mercury. This serious situation will last a long period. In order to alleviate mercury pollution, more work needs to do. 展开更多
关键词 chemical plant mercury contaminated rice C-FOS NO NOS
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Effects of seven different companion plants on cucumber productivity, soil chemical characteristics and Pseudomonas community 被引量:4
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作者 CHANG Chun-ling FU Xue-peng +2 位作者 ZHOU Xin-gang GUO Mei-yu WU Feng-zhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2206-2214,共9页
Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study,... Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study, seven different plant species were selected as companion plants for testing their effects on cucumber productivity. The effects of different companion plants on changes in soil chemical properties such as electrical conductivity (EC) and contents of essential nutrients as well as the structure and abundance of the soil Pseudomonas community were evaluated. The results showed a higher cucumber yield in the wheat/cucumber companion system than that in the cucumber monocultured and other companion cropping systems. The lowest phosphorus (P) and potassium (K) contents in the soil were found in the cucumber monocultured system, and the highest NO3+-N and NH4*-N contents were observed in the rye/cucumber companion system. PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR analysis showed that the trifolium/cucumber companion system increased the diversity of the soil Pseudomonas community, while the chrysanthemum/cucumber companion system increased its abundance. Interestingly, plant-soil feedback trials revealed that inoculating the soil of the wheat/cucumber companion system increased the growth of cucumber seedlings. In conclusion, the effects of different companion plants on cucumber productivity, soil chemical characteristics and the soil Pseudomonas community were different, and wheat was a more suitable companion plant for increasing cucumber productivity. In addition, the altered microbial community caused by companion cropping with wheat contributed to increased cucumber productivity. 展开更多
关键词 CUCUMBER companion plants soil chemical characteristics Pseudomonas community
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Physicochemical Properties of Combustion Ashes of Some Trees(Urban Pruning)Present in the Neotropical Region
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作者 John Freddy Gelves-Díaz Ludovic Dorkis +2 位作者 Richard Monroy-Sepúlveda Sandra Rozo-Rincón Yebrail Alexis Romero-Arcos 《Journal of Renewable Materials》 EI 2023年第10期3769-3787,共19页
Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion processes.In accordance with the above,in this paper,we wanted to study the ash from urban pru... Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion processes.In accordance with the above,in this paper,we wanted to study the ash from urban pruning residues that are generated in cities in the Neotropics.Species such as Licania tomentosa,Azadirachta indica,Ficus benjamina,Terminalia catappa,Leucaena leucocephala,Prosopis juliflora and Pithecellobium dulce were selected because they have been previously studied and showed potential for thermal energy generation.These materials were calcined in an oxidizing atmosphere and characterized by X-ray diffraction and fluorescence,scanning electron microscopy with microchemistry,BET surface area,thermal gravimetric analysis,and differential scanning calorimetry.The pH and apparent density were also established.The results show high basicity materials(average pH 10),a behavior associated with the presence of chemical elements such as calcium,potassium,magnesium,chlorine,phosphorus,and sulfur.Structurally,these materials have a very significant amorphous fraction(between 49%and 74.5%),the dominant crystalline phases are calcite,arcanite,sylvite,and hydroxyapatite.These ashes have low surface area and do not exceed 13 m^(2)/g.Two characteristic morphological aspects were observed in these ashes:a morphology of rounded grains where silicon content is highlighted,and lamellar morphologies where the presence of chlorine is highlighted.Thermally,these ashes show four significant mass loss events(400℃,430℃,680℃,and 920℃),causing mass losses that vary between 25%and 40%.Through this study,it was possible to establish that,from a chemical point of view,these ashes are less dangerous in comparison with those of a mineral coal that was used as a reference.However,they require additional treatments for their disposal due to their high basicity.Because of their composition,these ashes have the potential to be used in the ceramic and cement industries,and in the manufacture of fertilizers. 展开更多
关键词 Bottom ash chemical composition characterization MINERALOGY plant biomass pruning residues urban flora
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基于Plant Simulation的化纤自动落丝系统仿真实验分析
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作者 穆国鹏 徐志刚 +2 位作者 杨红亮 张博 苏武会 《高科技纤维与应用》 CAS 2024年第2期40-47,共8页
基于Plant Simulation软件,构建一种化纤自动落丝系统的3D数字化模型,对系统效率关键输入因子进行参数化设置,将系统各工位三维数字模型导入软件中建立层次化运动机构图形结构,并运用Simltalk语言实现三维动作仿真,通过基础物理参数设置... 基于Plant Simulation软件,构建一种化纤自动落丝系统的3D数字化模型,对系统效率关键输入因子进行参数化设置,将系统各工位三维数字模型导入软件中建立层次化运动机构图形结构,并运用Simltalk语言实现三维动作仿真,通过基础物理参数设置,保证了仿真数字化模型与现实系统更具一致性。通过多级实验设计分析了系统影响因子对于系统效率的影响特性曲线,并进一步通过动态参数化实验方法,计算出双输入因子对系统效能影响的敏感度。该实验结果可为化纤自动落丝系统的建设成本控制与可行性分析提供指导,具有较好的工程应用价值。 展开更多
关键词 化纤自动落丝 动态参数化 虚拟仿真 plant Simulation
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Use of Several Plant Materials and Chemicals to inhibit Soil Urease Activity and Increase Nitrogen Recovery Rate of Urea by Plant 被引量:6
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作者 XU WEIHONG, WANG ZHENGYIN, JIA ZHONGYUAN, HUANG YUN, YUAN LUJIANG and WANG JUANMEICollege of Resources and Environmental Science, Southwest Agricultural University, Chongqing 400716 (China) 《Pedosphere》 SCIE CAS CSCD 2002年第3期275-282,共8页
Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodora Hook., P1), robust eucalyptus (E. robusta Smith, P2), Nepal camphortree (Cinnamomum glanduliferum (Wall.) Nees, P3), tea (Camellia sinensis (Lin... Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodora Hook., P1), robust eucalyptus (E. robusta Smith, P2), Nepal camphortree (Cinnamomum glanduliferum (Wall.) Nees, P3), tea (Camellia sinensis (Linn.) O. Ktze. f., P4), oleander (Nerium indicum Mill, P5), rape (Brassica campestris L., P6),Chinese tallow tree (Sapium sebiferum L., P7), tung (Vernicia fordii (Hemsl.), P8), and croton (Croton tiglium L., P9), 7 chemicals, boric acid (C1), borax (C2), oxalic acid (C3), sodium oxalite (C4), sodium dihydrogen phosphate (C6), sodium silicate (C7) and sodium citrate (C8), and a natural organic substance,humic acid (C5), on urease activity of a neutral purple soil and recovery of urea nitrogen by maize were studied through incubation and pot experiments. Hydroquinone (HQ) was applied as the reference inhibitor. After incubation at 37 ℃ for 24 h, 7 inhibitors with higher ability to inhibit urease activity were selected and then incubated for 14 days at 25 ℃. Results of the incubation experiments showed that soil urease activity was greatly inhibited by them, and the inhibition effect followed an order of P2>P4>C3>C2>P3>C1>HQ>P1.The 7 selected materials reduced the accumulative amounts of N released from urea and the maximum urease activity by 11.7%~28.4% and 26.7%~39.7%, respectively, and postponed the N release peak by 2~4 days in the incubation period of 14 days under constant temperature, as compared to the control (no inhibitor).In the pot experiment with the 7 materials at two levels of addition, low (L) and high (H), the C1 (H), C3(H), C1 (L), P4 (L) and C2 (L) treatments could significantly increase the dry weights of the aboveground parts and the total biomass of the maize plants and the apparent recovery rate of urea-N was increased by 6.3%~32.4% as compared to the control (no hibitor). 展开更多
关键词 土壤脲酶 尿素 植物 化学品 脲酶活性
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Current Seasonal Variations in Physicochemical and Heavy Metals Parameters of Sewage Treatment Plant Effluent and Suitability for Irrigation 被引量:2
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作者 Chandan Maurya Janendra Nath Srivastava 《Journal of Water Resource and Protection》 2019年第7期852-865,共14页
The study aims to investigate the current extent of physicochemical parameters and heavy metal contamination in the effluent of the Jaganpur sewage treatment plant (STP), Dayalbagh, Agra India. Majority of the nearby ... The study aims to investigate the current extent of physicochemical parameters and heavy metal contamination in the effluent of the Jaganpur sewage treatment plant (STP), Dayalbagh, Agra India. Majority of the nearby farmers have access to use of STP effluent in irrigation purposes for growing major edible crops. The problems of using STP effluent for irrigation purpose, continuous water quality analysis required. To check the quality of irrigation water, substantial physicochemical parameters accordance to Indian Standards (IS-Reaffirmed 2002/2003) analysed to calculate Sodium absorption ratio (SAR) and Residual sodium carbonate (RSC). To estimate the heavy metal pollution index (HPI) and metal quality index (MQI), toxic Heavy metals such as As, Cr, Mn, Fe, Ni, Cu, Zn, Pd, Cd, Co, and B also determined in the STP effluent with an AAS and results verified with ICP-OES against certified standards. The high value of SAR (range 13 to 20) and RSC (range -10 to 11) in STP effluent exceeded the permissible limit for irrigation purpose. On the other hand, HPI and MQI values (1692.4 and 58.1, respectively) show that high metal contamination mainly due to industrial and domestic wastewater does not treat appropriately in the sewage treatment plant. Thus it is suggested that further studies are carried out on the STP effluents to improve the water quality through proper treatment. Treated wastewater used for irrigation purposes needs to analyse the contamination like heavy metals and pinpoint the pollution sources. 展开更多
关键词 Heavy Metals PHYSICO-chemical Parameters SEWAGE Treatment plants EFFLUENT IRRIGATION Water
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Distribution and Chemical Composition of Monocarpic Plants of the Apiaceae Family in Tien Shan Mountain
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作者 Ilkhom Uktamovich Mukumov Murtoza Abdivalievich Hasanov +1 位作者 Yulduzoy Erkin Kizi Ikromova Tolibjon Mukimov 《American Journal of Plant Sciences》 2022年第2期265-276,共12页
The article presents materials on the distribution and data on the chemical composition of monocarpic plants of the Apiaceae family in the Tien Shan Mountains.
关键词 Monocarpic plants chemical Composition MOUNTAIN Apiaceae Family plant Species
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Effect of Organic Fertilizer Doses on the Plant Growth,Essential Oil Production and Chemical Substances of "Carqueja" over Two Harvest Moments
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作者 Daniel Garcia Paulo Sérgio Siberti da Silva +3 位作者 Marcos Roberto Furlan Monica Tiho Chisaki Isobe Marcia Ortiz May Marques Lin Chau Ming 《Journal of Agricultural Science and Technology(B)》 2017年第2期114-124,共11页
This study aimed to investigate, for the first time, the plant growth, essential oil content and their chemical substances ofBaccharis trimera (Less.) DC., the first Brazilian variety of medicinal plant, in response... This study aimed to investigate, for the first time, the plant growth, essential oil content and their chemical substances ofBaccharis trimera (Less.) DC., the first Brazilian variety of medicinal plant, in response to five doses of organic fertilizer (0, 10, 20,30, 40 and 50 ton/ha) over two harvest moments-120 d and 242 d after transplanting (DAT). The work was carried out fromFebruary to October 2011 at the experimental farm of the Sao Paulo State University "Julio de Mesquita Filho" (UNESP), Brazil.The seedlings of B. trimera var. CPQBA-1 were respectively transplanted into experiment plots under six treatments: 0, 10, 20, 30,40 and 50 ton/ha of organic fertilizer. Each treatment had four replications and each plot consisted of 12 plants. Then they wereharvested at 120 DAT and 242 DAT, and the essential oil were extracted by hydrodistillation and analyzed by gas chromatograph.The results were subjected to analysis of variance and the means were analysed using Tukey's test (5%) followed by a regressionanalysis. The fertilizer dose significantly influenced the height of the plants in the second harvest, while the higher dose of organicfertilizer positively impacted the essential oil content in the first harvest. Also, the level of organic fertilizer was directly correlatedwith the production of dry matter during the regrowth. Twenty-seven substances were identified in the essential oil samples, and themajor components were: bicyclogermacrene, trans-caryophyllene, germacrene-D, spathulenol and caryophyllene oxide. Thesefindings suggest that to obtain higher yields of dry matter ofB. trimera, it should be harvested around 242 DAT and organic fertilizershould be applied approximately to 50 ton/ha. Furthermore, higher doses of organic fertilizer and harvest at 120 DAT is able toincrease the essential oil content. 展开更多
关键词 BACCHARIS trimera BRAZILIAN MEDICINAL plant dry matter chemical substances bicyclogermacrene.
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Variability in Content and Chemical Constituents of Essential Oil of Sweet Basil (Ocimum basilicum L.) Obtained from Aerial Plant Parts
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作者 Yasmin A. A. Aburigal Nada B. Hamza +4 位作者 Ismail H. Hussein Elfadl Y. Elmogtaba Tanzeil H. Osman Faiza I. Ali Awatif A. M. Siribel 《Advances in Bioscience and Biotechnology》 2016年第3期183-187,共5页
Sweet basil (Ocimum basilicum L.) project that is being conducted at the National Oilseed Processing Research Institute (NOPRI) aims at exploiting the genetic diversity and associated phenotypic variation in the inves... Sweet basil (Ocimum basilicum L.) project that is being conducted at the National Oilseed Processing Research Institute (NOPRI) aims at exploiting the genetic diversity and associated phenotypic variation in the investigated basil germplasm and evaluating key factors such as variety, plant ontogeny and plant parts that affect yield, chemical constituents, aroma and flavor of essential oils. This paper discussed the variability inessential oils content and chemical constituents of the aerial plant parts of the basil. An open-air pot experiment was carried out using three accessions provided by Agricultural Research Corporation-Genetic Resources Unit, Sudan. The essential oils were hydro distilled from the aerial parts, flowers, leaves, stems, using Clevenger apparatus. The chemical constituents of the essential oils were determined by Gas Chromatography-Mass Spectrometry (GC-MS). As the hydro distillation yielded no oil from the stem, we present only the results for leaves and flowers. The results revealed that the essential oil content varied with a range of 0.29% to 0.33% for flowers and 0.32% to 0.48% for leaves. As usual, the content of essential oils was higher in leaves than in flowers. The Silate-Egyptian accession had the lowest essential oil content obtained from leaves and flowers. However, South Darfur accession from Sudan had the highest oil content but did not significantly differ from Kennana accession. Several oil components were identified based upon comparison of their mass spectral data with those of reference compounds published in literature or stored in a computer library. The combined GC-MS analysis showed that methyl eugenol was the major constituent of the essential oil of Kennana accession. While the major constituent of essential oil of South-Darfur and Silate-Egyptian accessions were germacrene and linalool, respectively. 展开更多
关键词 Sweat Basil Ocimum basilicum L. Essential Oils HYDRODISTILLATION plant Parts chemical Constituents
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Advances in Measures of Reducing Chemical Pesticides to Control Plant Diseases
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作者 Yanmin Sun Jinfeng Han +1 位作者 Xiaoli Chen Hui Guo 《Plant Diseases and Pests》 CAS 2021年第5期1-6,16,共7页
In order to provide the technological support for further implementing measures of reducing chemical pesticide to control plant diseases,the research progress on non-chemical pesticide measures to control plant diseas... In order to provide the technological support for further implementing measures of reducing chemical pesticide to control plant diseases,the research progress on non-chemical pesticide measures to control plant diseases are reviewed from the aspects of agricultural control,botanical pesticide control and microbial pesticide control,and the development prospects are proposed,including accelerating innovative research on botani-cal pesticide control such as Chinese herb extracts,and screening microbial pesticides from valuable bio-control bacteria or plant endophyte metabolites for commercial production and utilization. 展开更多
关键词 Reduction of chemical pesticide Agricultural control Botanical pesticide Microbial pesticide plant disease Disease control
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WEIFANG CHEMICALS PLANT
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《China's Foreign Trade》 1994年第11期45-45,共1页
As a large, key enterprise in Weifang City and Shandong, the Weifang Chemicals Plant has developed an annual production capacity of 35.000 tons of caustic soda, 10,000 tons of polyvinyl chloride, 6,000 tons of polyeth... As a large, key enterprise in Weifang City and Shandong, the Weifang Chemicals Plant has developed an annual production capacity of 35.000 tons of caustic soda, 10,000 tons of polyvinyl chloride, 6,000 tons of polyethylene chloride, 15.000 tons of chlorine liquid. 10,000 tons of synthetic hydrochloric acid. 7.000 tons of etectride stone and 20. 展开更多
关键词 AS WEIFANG chemicalS plant
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Agent Orange Chemical Plant Locations in the United States and Canada: Environmental and Human Health Impacts
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作者 Kenneth R. Olson David R. Speidel 《Open Journal of Soil Science》 CAS 2022年第8期363-426,共64页
During the Vietnam War, millions of liters of six tactical herbicides were sprayed on the southern Vietnam landscape to defoliate forests, to clear military perimeters and to destroy enemy food supplies. The environme... During the Vietnam War, millions of liters of six tactical herbicides were sprayed on the southern Vietnam landscape to defoliate forests, to clear military perimeters and to destroy enemy food supplies. The environmental and human health impacts of spraying these herbicides, especially Agent Orange and those formulated with mixtures that included 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) which was contaminated with 2,3,7,8-tetracholorodibenzo-p-dioxin (TCDD) have been documented over the last 60 years. The dioxin TCDD clean-up efforts at former military bases and other Vietnam hotspots are ongoing. However, the lesser-told story was the environmental and human health impacts on the communities and chemical plant workers who manufactured Agent Orange and other herbicides that became contaminated with dioxin TCDD in the manufacturing processes at seven locations in the United States and one site in Canada. The pollution at these chemical plant sites, adjacent rivers and groundwater is well known within each affected state or province but not widely recognized beyond their localities. In this paper we assess the national long-term effects on land, groundwater and river resources where Agent Orange and other agricultural herbicides containing 2,4,5-T with unknown amounts of dioxin TCDD were manufactured, transported, and temporarily stored. The sites where residual tactical herbicides with contaminated by-products were applied to public lands or disposed of by military and civilian workers within the United States and Canada are identified. After 60 years, these communities are still paying the price for the U.S. Government, DOD and USDA decisions to provide and use agricultural herbicides as tactical chemical weapons during the Vietnam War (1962-1971). There have been human health issues associated with the chemical manufacture, transport, storage and disposal of these herbicides related to workers who moved these chemical weapons from United States and Canada to SE Asia. Most of these dioxin contaminated tactical herbicides were transported via railroads to ports at Mobile, Alabama and Gulfport, Mississippi. They were then loaded on ocean-going ships and transported via the Panama Canal for use during the Vietnam War. The objective of this study is to document the environmental and human consequences of the manufacture of tactical herbicides with dioxin TCDD and arsenic on the chemical plant, transportation, application, storage and disposal workers. The costs of cleanup of these North America chemical plant sites, transportation corridors, temporary and long-term storage areas, supply chain storage facilities with residual tactical herbicide, application, and disposal sites to date, is in the billions of dollars. Billions have been spent on hazardous waste incineration to destroy the dioxin TCDD or bury it in certified landfills. Government mandated environmental covenants are on titles of properties still contaminated with high levels of dioxin TCDD. If landowners attempt to rescind land use restrictions, many more billions of dollars will be needed to finish the environmental cleanup and restore natural resources. These cost estimates do not include the billions of dollars needed to treat the effects of dioxin TCDD exposure of U.S. and Canadian civilian workers who manufactured and handled these contaminated herbicides during the Vietnam War as well as address human health issues of their offspring. 展开更多
关键词 Dioxin TCDD Arsenic chemical plant Workers CHLORACNE Cancer Herbicides Cacodylic Acid Monsanto Dow Nitro Midland Elmira Uniroyal Times Beach MISSOURI Gagetown Incineration Certified Landfill Environmental Covenants
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Chemical Composition and Ruminal Digestibility of Ceratoides, a Salt-tolerant Perennial Plant,at Different Years
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作者 SUN H ISHIKAWA N +5 位作者 VIN G SHIMIZU K CAO W Hasiqiqige AMARI M Alata 《畜牧与饲料科学》 2012年第11期108-108,共1页
It has been proposed that salt-tolerant plant could be used as a feed resource for ruminants whereby salt would be removed from salinized land (Asian -Aust. J. Anim. Sci. (2002) 15:998 -1001). Ceratoides arborescens (... It has been proposed that salt-tolerant plant could be used as a feed resource for ruminants whereby salt would be removed from salinized land (Asian -Aust. J. Anim. Sci. (2002) 15:998 -1001). Ceratoides arborescens (Losinsk.) Tsien et C. G. Ma is known as a drought-and salt-tolerant plant,a kind of shrubs, growing in semi-arid land of Inner Mongolia. Because the covering effect of the perennial plant as a mulch over the soil might be expected, the optimum covering effect would be obtained after the growth period.The perennial plant produces seeds around summer and end its growth thereafter. Nutrient value of the perennial salt-tolerant plant, however,had not been reported in flowering period at different year. It is necessary to know the ruminal degradability of the plants of each growing year in order to determine the regimen to diet for ruminants. The present experiment,therefore,was undertaken to analyze the digestibility and chemical composition of Ceratoides arborescens as feed for ruminants. 展开更多
关键词 a Salt-tolerant Perennial plant at Different Years chemical Composition and Ruminal Digestibility of Ceratoides
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Toxic Gas Put 161 Workers of Jilin Chemical Fiber Plant in Hospital
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《China Textile》 2009年第6期18-18,共1页
A news briefing held on May 13 by local government in Jilin city of Jilin province released that 161 workers got sick symptoms as a result of their contact with an unidentified gas emitting from Jilin Chemical Fiber G... A news briefing held on May 13 by local government in Jilin city of Jilin province released that 161 workers got sick symptoms as a result of their contact with an unidentified gas emitting from Jilin Chemical Fiber Group Corp. 展开更多
关键词 Toxic Gas Put 161 Workers of Jilin chemical Fiber plant in Hospital
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Spatial heterogeneity of soil chemical properties between Haloxylon persicum and Haloxylon ammodendron populations 被引量:11
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作者 Li, CongJuan Li, Yan +2 位作者 Ma, Jian Fan, LianLian Wang, QinXue 《Journal of Arid Land》 SCIE 2010年第4期257-265,共9页
Spatial heterogeneity is a ubiquitous feature in natural ecosystems, especially in arid regions. Different species and their discontinuous distribution, accompanied by varied topographic characteristics, result in soi... Spatial heterogeneity is a ubiquitous feature in natural ecosystems, especially in arid regions. Different species and their discontinuous distribution, accompanied by varied topographic characteristics, result in soil resources distributed differently in different locations, and present significant spatial heterogeneity in desert ecosystems. In this study, conventional and geostatistical methods were used to identify the heterogeneity of soil chemical properties in two desert populations, Haloxylon persicum Bunge ex Boss., which dominates on the slopes and tops of sand dunes and Haloxylon ammodendron (C. A. Mey.) Bunge, which inhabits interdunes in the Gurbantunggut Desert of Xinjiang, China. The results showed that soil pH, electrical conductivity (EC), soil organic carbon (SOC), available nitrogen (AN) and available phosphorus (AP) were significantly higher in H. ammodendron populations than that in H. persicum. The coefficient of variation (CV) indicated that (1) most parameters presented a moderate degree of variability (10% 【 CV 【 100%) except pH in both plots, (2) the variability of soil pH, EC and AP in H. ammodendron populations was higher than that in H. persicum populations, and (3) SOC and AN in H. ammodendron populations were lower than that in H. persicum populations. Geostatistical analysis revealed a strong spatial dependence (C0/(C0+C) 【 25%) within the distance of ranges for all tested parameters in both plots. The Kriging-interpolated figures showed that the soil spatial distribution was correlated with the vegetation distribution, individual size of plants, and the topographic features, especially with the plants nearest to sampling points and the topographic features. In each plot, soil EC, SOC, AN and AP presented similar distributions, and fertile islands and salt islands occurred in both plots but did not affect every individual plant, since the sampling distance was larger than the size of such fertile islands. The results of topographic effects on soil heterogeneity suggested significant differences between the interdunes and dune-tops. Different topographic characteristics (physical factors) between plots result in the differences in SOC, AN and AP, while the heterogeneity of soil pH and EC arise from plant species and their distribution (biotic factor). Such biotic and physical factors did not occur in isolation, but worked together on soil heterogeneity, and played important parts in improving the soil properties. Hence these factors were ecologically valuable in the highly resource-stressed arid study area. 展开更多
关键词 fertile island GEOSTATISTICS plant population soil chemical properties spatial heterogeneity
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Spatiotemporal simulation and predication of heavy metal(loid) concentrations in coal chemical industrial areas with a soil environmental capacity model 被引量:6
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作者 Kai Zhang Jiajun Yang +1 位作者 Yuning Ji Yu Xia 《International Journal of Coal Science & Technology》 EI 2018年第4期508-518,共11页
Heavy metal (loid)(HM) accumulation in the soil and the HM spatiotemporal distribution have important implication for soil pollution prevention and remediation. The present study investigated the concentrations and sp... Heavy metal (loid)(HM) accumulation in the soil and the HM spatiotemporal distribution have important implication for soil pollution prevention and remediation. The present study investigated the concentrations and spatiotemporal distributions of lead (Pb), mercury (Hg), cadmium (Cd), chromium (Cr) and arsenic (As) in the topsoil of a coal chemical plant in Ningxia Aulonomous region (Ningxia), China. Topsoil samples (/?= 153) were obtained using the checkerboard method, and the HM concentrations were determined. The soil residual rates of the five HMs were measured with leaching experinients and were applied in a soil environmental capacity model to predict the quarHitiHive variation of the HM concentrations. The predicted results were employed to estimate the HM spatiotemporal distribution within 2() years with the Kriging technique. The number of sampling sites, where all five HM concentratio ns exceed their corresponding background values in Ningxia, would be increased from 0 to 90% within 1() years of the plant operation. In addition, Pb and Cd were distributed along the traffic routes. Mercury and As were distributed near fuel gas emission vents. Chromium was mainly accumulated in slag dumps. The study may provide the theoretical and practical foun d at ion for future HM pollution control in coal chemical plants. 展开更多
关键词 COAL chemical plant Soil Heavy metal(loid) KRIGING SIMULATION prediction
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Research Progress on the Natural Anti-peptic Ulcer Chemical Structures 被引量:1
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作者 简舒心 田应园 +2 位作者 汪鋆植 胡为民 黄年玉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第11期1703-1710,共8页
Natural products provide an important original source of structural diversity for finding new compounds as anti-peptic ulcer drugs. The present review highlights some recent advances on gastro-protective flavonoids, t... Natural products provide an important original source of structural diversity for finding new compounds as anti-peptic ulcer drugs. The present review highlights some recent advances on gastro-protective flavonoids, terpenes, alkaloids, steroids, phenylpropanoids,glycosides and chromenes from natural herbs or traditional medicinal plants, and helps us analyze the structure-activity relationship(SAR) of natural products in healing of peptic ulcer for further drug development. 展开更多
关键词 peptic ulcer natural products medicinal plants chemical structures structure-activity relationship
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An updated review on pharmacological activities and phytochemical constituents of evening primrose(genus Oenothera)
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作者 Rebecca Munir Nabil Semmar +1 位作者 Muhammad Farman Naseem Saud Ahmad 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第11期1046-1054,共9页
Genus Oenothera includes medicinal plants that are distributed throughout the world and are known since ancient times. Popular indications of different species of this genus include treatment of inflammations, diabete... Genus Oenothera includes medicinal plants that are distributed throughout the world and are known since ancient times. Popular indications of different species of this genus include treatment of inflammations, diabetes, microbial infections, ulcers, tumors, kidney and liver problems. The plants of this genus are a botanical source for various pharmaceutically active components like sterols, alkaloids, phenolic acids, flavonoids, triterpenoids, saponins, biflavonols and tocopherols. This review article is a compilation of chemical composition and biological activities of the various species of the genus Oenothera. 展开更多
关键词 OENOTHERA Medicinal plants chemical composition Biological activities
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Advances in Chemical Constituents and Pharmacological Activity of Pholidota spp.
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作者 Xiucai WU Shuang LIANG Zhengying SU 《Medicinal Plant》 CAS 2020年第2期13-15,共3页
In recent years,a large number of studies have shown that the effective compounds extracted from Pholidota spp.have pharmacological activities such as anesthesia,analgesia,anti-fatigue,anti-hypoxia,anti-tumor and anti... In recent years,a large number of studies have shown that the effective compounds extracted from Pholidota spp.have pharmacological activities such as anesthesia,analgesia,anti-fatigue,anti-hypoxia,anti-tumor and anti-oxidant.Because of significant activity and small side effects,Pholidota spp.have attracted much attention.In this article,the effective chemical constituents and pharmacological activity of Pholidota spp.are reviewed comprehensively in order to provide reference for the further rational development of Pholidota spp.and development of new drugs. 展开更多
关键词 Pholidota spp. MEDICINAL plant chemical CONSTITUENT PHARMACOLOGICAL activity
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A Toxicological Assessment of Endocrine Disrupting Chemicals Found in the BMW (Border, Midland and Western) Region of Ireland
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作者 Kathryn M. Quinn-Hosey James J. Roche +1 位作者 Andrew M. Fogarty Concepta A. Brougham 《Journal of Environmental Protection》 2012年第4期304-315,共12页
A battery of tests was established to determine the oestrogenic, mutagenic and genotoxic potential of two categories of endocrine disrupting chemicals (EDCs), phthalates and alkylphenols. Diisononylphthalate (DINP), d... A battery of tests was established to determine the oestrogenic, mutagenic and genotoxic potential of two categories of endocrine disrupting chemicals (EDCs), phthalates and alkylphenols. Diisononylphthalate (DINP), diethylhexylphthalate (DEHP), dibutylphthalate (DBP), diisododecylphthalate (DIDP) and 4-nonylphenol (4-NP) were oestrogenic in the yeast estrogen screen (YES) assay and potently oestrogenic in the MVLN and E-SCREEN assays at environmentally relevant concentrations. DINP and 4-NP were mutagenic in the Ames assay and also induced significant levels of unscheduled DNA synthesis and DNA strand breakage. Significant induction in the percentage of cells containing micronuclei was observed after treatment with DINP, DEHP and 4-NP. In addition, sewage effluents from sewage treatment plants (STPs) in the Border, Midlands and Western (BMW) region of Ireland were significantly oestrogenic in the YES assay. Moreover, analysis of levels of phthalates and alkylphenol identified in Irish rivers receiving treated effluent showed potent oestrogenicity in the YES assay. The proliferative and genotoxic ability of the phthalates and alkylphenol, and the oestrogenicity of the treated effluents reported here, is significant as these EDCs and EDCs within the effluent may play a role in the etiology of human abnormalities. 展开更多
关键词 Endocrine Disrupting chemicals (EDCs) Proliferation TRANSACTIVATION Mutagenicity Genotoxicity Sewage Treatment plant (STP) BORDER Midlands and WESTERN (BMW) REGION of IRELAND
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