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Micro-textures in plagioclase from 1994-1995 eruption, Barren Island Volcano: Evidence of dynamic magma plumbing system in the Andaman subduction zone 被引量:4
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作者 M.L.Renjith 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第1期113-126,共14页
A systematic account of micro-textures and a few compositional profiles of plagioclase from high-alumina basaltic aa lava erupted during the year 1994-1995, from Barren Island Volcano, NE India ocean, are presented fo... A systematic account of micro-textures and a few compositional profiles of plagioclase from high-alumina basaltic aa lava erupted during the year 1994-1995, from Barren Island Volcano, NE India ocean, are presented for the first time. The identified micro-textures can be grouped into two categories: (i) Growth related textures in the form of coarse/fine-sieve morphology, fine-scale oscillatory zoning and resorption surfaces resulted when the equilibrium at the crystal-melt interface was fluctuated due to change in temperature or H20 or pressure or composition of the crystallizing melt; and (ii) morphological texture, like glomerocryst, synneusis, swallow-tailed crystal, microlite and broken crystals, formed by the influence of dynamic behavior of the crystallizing magma (convection, turbulence, degassing, etc.). Each micro-texture has developed in a specific magmatic environment, accordingly, a first order magma plumbing model and crystallization dynamics are envisaged for the studied lava unit. Magma generated has undergone extensive fractional crystallization of An-rich plagioclase in stable magmatic environment at a deeper depth. Subsequently they ascend to a shallow chamber where the newly brought crystals and pre-existing crystals have undergone dynamic crystallization via dissolution-regrowth processes in a convective self- mixing environment. Such repeated recharge-recycling processes have produced various populations of plagioclase with different micro-textural stratigraphy in the studied lava unit. Intermittent degassing and eruption related decompression have also played a major role in the final stage of crystallization dynamics. 展开更多
关键词 Micro-texture Plagioclase Magma chamber process barren Island Volcano Andaman subduction zone
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Inheritance of Ear Tip-Barrenness Trait in Maize 被引量:2
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作者 MENG Zhao-dong ZHANG Fa-jun +4 位作者 DING Zhao-hua SUN Q i WANG Li-ming GUO Qing-fa WANG Hong-gang 《Agricultural Sciences in China》 CAS CSCD 2007年第5期628-633,共6页
The aim of this paper is to study the inheritance pattern of ear tip-barrenness trait in maize (Zea mays L.). Ear tipbarrenness trait in maize can be classified into two types, tip-barren and tip-barrenless. Two inb... The aim of this paper is to study the inheritance pattern of ear tip-barrenness trait in maize (Zea mays L.). Ear tipbarrenness trait in maize can be classified into two types, tip-barren and tip-barrenless. Two inbred lines, lx01-3 (tipbarrenless type), wx04-1 (tip-barren type), and their F1, F2, BC1, BC2 generations were analyzed on their ear tip-barrenness types. Results showed that F1 was tip-barren type; the ratio of tip-barren type versus tip-barrenless type followed a 12.78: 1 ratio in F2 segregation population and a 2.75:1 ratio in BC1. Z2 test indicated that the trait of ear tip-barrenness type followed an inheritance pattern of 2 duplicate dominant genes. SPSS analysis indicated that the trait of ear tip-barrenness length is of abnormal distribution. Above results mean that: (1) The trait of maize ear tip-barrenness type is controlled by 2 duplicate dominant genes; tip-barren type is dominant over tip-barrenless type; (2) the trait of tip-barrenness length is a quantitative character controlled by polygene with major genes expected. 展开更多
关键词 MAIZE ear tip-barrenness type fructification habit dominant inheritance duplicate genes
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Genome-wide association study and metabolic pathway prediction of barrenness in maize as a response to high planting density
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作者 ZHANG Xu-huan LIU Hao +9 位作者 MA Xu-hui ZHOU Gu-yi RUAN Hong-qiang CUI Hong-wei PANG Jun-ling KHAN Ullah Siffat ZONG Na WANG Ren-zhong LENG Peng-fei ZHAO Jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第12期3514-3523,共10页
Increasing the planting density is one way to enhance grain production in maize.However,high planting density brings about growth and developmental defects such as barrenness,which is the major factor limiting grain y... Increasing the planting density is one way to enhance grain production in maize.However,high planting density brings about growth and developmental defects such as barrenness,which is the major factor limiting grain yield.In this study,the barrenness was characterized in an association panel comprising 280 inbred lines under normal(67500 plants ha–1,ND)and high(120000 plants ha–1,HD)planting densities in 2017 and 2018.The population was genotyped using 776254 single nucleotide polymorphism(SNP)markers with criteria of minor allele frequency>5%and<20%missing data.A genome-wide association study(GWAS)was conducted for barrenness under ND and HD,as well as the barrenness ratio(HD/ND),by applying a Mixed Linear Model that controls both population structure and relative kinship(Q+K).In total,20 SNPs located in nine genes were significantly(P<6.44×10–8)associated with barrenness under the different planting densities.Among them,seven SNPs for barrenness at ND and HD were located in two genes,four of which were common under both ND and HD.In addition,13 SNPs for the barrenness ratio were located in seven genes.A complementary pathway analysis indicated that the metabolic pathways of amino acids,such as glutamate and arginine,and the mitogen-activated protein kinase(MAPK)signaling pathway might play important roles in tolerance to high planting density.These results provide insights into the genetic basis of high planting density tolerance and will facilitate high yield maize breeding. 展开更多
关键词 Zea mays L high planting density barrenness genome-wide association study MAPK pathway
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Investigation on the Green Planting Situation of Dongchuan Barren Hills in Kunming City
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作者 Haifan WANG 《Agricultural Biotechnology》 CAS 2018年第5期252-255,共4页
Dongchuan District of Kunming City has undulating terrain with large fluctuations, fragile ecological environment, low rainfall and high evaporation, coupled with frequent debris flow activities, resulting in very low... Dongchuan District of Kunming City has undulating terrain with large fluctuations, fragile ecological environment, low rainfall and high evaporation, coupled with frequent debris flow activities, resulting in very low forest coverage rate in Dongchuan. In this study, a comprehensive and systematic investigation was carried out to the green planting of barren hills in Dongchuan District from January to June, 2016. The results showed that the major planting tree species in the region with an altitude of less than 1 600 m were Leucaena leucocephala, Cupressus torulosa, L. leucocephala, C. torulosa, Celtis yunnanensis, Melia azedarach , among which L. leucocephala had become of pioneer tree species of afforestation in the Dongchuan dry-hot valley. The major planting tree species at the altitude of 1 600-2 500 m were C. torulosa, Sabina chinensis, Alnus nepalensis, C. yunnanensis, and Pinus armandi , and at the altitude of over 2 500 m, the major tree species were Sabina chinensis, Abies georgei var. smithii, P.densata. Based on the investigation, suggestions were proposed for the existing problems in the greening and planting of Dongchuan barren hills, in order to provide certain theoretical basis for the sustainable development of forestry in Dongchuan. 展开更多
关键词 Dongchuan Ecological environment barren hill Green planting
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Arbuscular mycorrhizal fungal communities associated with switchgrass(Panicum virgatum L.)in the acidic,oligotrophic pine barrens ecosystem
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作者 Molly Bindell Jing Luo +5 位作者 Emily Walsh Nicole EWagner Stephen JMiller Guohong Cai Stacy ABonos Ning Zhang 《Grass Research》 2021年第1期3-12,共10页
Arbuscular mycorrhizal(AM)fungi contribute globally to ecosystem services and play an important role in sustainable crop production.However,it is unclear which factors contribute most to their colonization and communi... Arbuscular mycorrhizal(AM)fungi contribute globally to ecosystem services and play an important role in sustainable crop production.However,it is unclear which factors contribute most to their colonization and community structure at different sites,particularly in understudied ecosystems.This study investigated the AM fungal communities associated with switchgrass(Panicum virgatum L.)in the understudied acidic and oligotrophic pine barrens ecosystem using next-generation sequencing.Switchgrass was also sampled from agroecosystems,as well as,from a native prairie for comparison.The pine barrens switchgrass harbored a distinct AM fungal community−Acaulospora and Ambispora were almost exclusively found in the pine barrens sites,and some of these species may represent undescribed taxa.Glomus was the most ubiquitous AM fungal genus recovered from all sites.This study suggests differences in the AM fungal community structure under different soil properties and land uses.This is the first sequence-based report of the AM fungal communities in the pine barrens ecosystem. 展开更多
关键词 barren SOIL ACIDIC
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Presence of Black Carbon in Soil due to Forest Fire in the New Jersey Pine Barrens
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作者 Bente Foereid Johannes Lehmann +1 位作者 Christopher Wurster Michael Bird 《Journal of Earth Science and Engineering》 2015年第2期91-97,共7页
关键词 森林火灾 新泽西州 松树林 黑碳 土壤 生产速度 生态因子 消防管理
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乏情季节应用孕酮微囊包被液态制剂对奶山羊同期发情人工授精效果对比分析
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作者 董志岷 王春 +6 位作者 郭雅娟 贺佳唯 刘艳琴 朝格吉乐图 范佳乐 王贵 杜金娥 《中国饲料》 北大核心 2024年第4期13-16,共4页
奶山羊发情具有一定的季节性,每年的4~7月份属于乏情季节,为了提高种山羊的利用率,扩大种群规模,实现全年均衡生产,必须突破乏情季节奶山羊繁殖率低的瓶颈。本试验将150只适繁奶山羊随机分为3组,每组50只,第1组以全混合日粮(TMR)为载体... 奶山羊发情具有一定的季节性,每年的4~7月份属于乏情季节,为了提高种山羊的利用率,扩大种群规模,实现全年均衡生产,必须突破乏情季节奶山羊繁殖率低的瓶颈。本试验将150只适繁奶山羊随机分为3组,每组50只,第1组以全混合日粮(TMR)为载体投放孕酮微囊包被液态制剂+PMSG+PG处理,第2组以阴道硅胶支架(CIDR)+PMSG+PG处理,第3组不做任何处理。结果表明,在相同饲养条件下,第1、2组同期发情率较高,差异不显著(P> 0.05),但显著高于第3组(P <0.05);但发情母羊人工授精后的妊娠率显示第1组和第3组显著高于第2组(P <0.05),说明在乏情季节对奶山羊应用孕酮微囊包被液态制剂可以有效减少生殖道投药的不利影响,可以有效提高种羊的利用率,为实现舍饲奶山羊快速扩繁提供技术支撑。 展开更多
关键词 乏情季节 孕酮微囊包被液态制剂 CIDR 同期发情
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络合沉淀法—硫化沉淀法联合处理铜氰贫液试验研究
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作者 刘强 伍赠玲 +3 位作者 高世康 王弘 韩良 林国钦 《黄金》 CAS 2024年第2期89-92,共4页
针对某黄金生产企业产生的铜氰贫液,采用络合沉淀法—硫化沉淀法联合进行回收处理。在络合沉淀法五水合硫酸铜投加量3.0 g/L、焦亚硫酸钠投加量2.0 g/L,硫化沉淀法九水合硫化钠加药量0.35 g/L条件下,铜氰贫液中总氰化合物、铜和硫氰酸... 针对某黄金生产企业产生的铜氰贫液,采用络合沉淀法—硫化沉淀法联合进行回收处理。在络合沉淀法五水合硫酸铜投加量3.0 g/L、焦亚硫酸钠投加量2.0 g/L,硫化沉淀法九水合硫化钠加药量0.35 g/L条件下,铜氰贫液中总氰化合物、铜和硫氰酸盐质量浓度从150.84 mg/L、121.46 mg/L、252.65 mg/L降至0.44 mg/L、86.17 mg/L、1.23 mg/L,回收金、银、铜的产值为116.62元/m^(3),扣除药剂成本后产生经济效益55.44元/m^(3)。研究结果为类似氰化企业铜氰贫液的净化处理提供参考。 展开更多
关键词 铜氰贫液 络合沉淀 硫化沉淀 联合处理 总氰化合物
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相关细胞因子对不孕症的影响分析及育龄期女性子宫内膜异位症预测模型构建
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作者 金凤梅 马清杰 付久园 《河北医学》 CAS 2024年第3期488-493,共6页
目的:分析相关细胞因子对不孕症的影响,并建立育龄期女性子宫内膜异位症治疗后不孕症的预测模型。方法:纳入2020年3月至2022年3月医院108例育龄期女性子宫内膜异位症患者,所有患者入院时均接受血清学检测。随访1年,观察其自然妊娠情况,... 目的:分析相关细胞因子对不孕症的影响,并建立育龄期女性子宫内膜异位症治疗后不孕症的预测模型。方法:纳入2020年3月至2022年3月医院108例育龄期女性子宫内膜异位症患者,所有患者入院时均接受血清学检测。随访1年,观察其自然妊娠情况,依据妊娠结果分为自然妊娠组与不孕组,对比两组基线资料及血清学检测指标,建立育龄期女性子宫内膜异位症预测模型,并分析相关细胞因子对不孕症的影响。结果:随访1年,108例育龄期女性子宫内膜异位症患者中成功妊娠66例(61.11%),未成功妊娠42例(38.89%);不孕组子宫内膜异位症Ⅲ期-Ⅳ期、未接受促排卵治疗的患者占比高于自然妊娠组(χ2=6.495、5.945,P<0.05);不孕组白细胞介素-1β(IL-1β)、白细胞介素-18(IL-18)、肿瘤坏死因子-α(TNF-α)水平高于自然妊娠组(t=7.345、4.095、5.739,P<0.05);绘制血清学细胞因子预测育龄期女性子宫内膜异位症患者发生不孕症的受试者工作曲线(ROC),结果显示,IL-1β、IL-18、TNF-α水平对育龄期女性子宫内膜异位症患者发生不孕症具有一定预测价值(AUC=0.837、0.711、0.779,P<0.05),联合预测价值更高(AUC=0.864);经Logistic回归分析,结果显示,子宫内膜异位症Ⅲ期-Ⅳ期、未接受促排卵治疗、高IL-1β、IL-18、TNF-α水平是育龄期女性子宫内膜异位症患者发生不孕症的危险因素(OR=4.730、4.173、16.216、1.012、4.631,P<0.05),将其带入回归方程可得:Logit(P)=-15.285+1.554X1+1.429X2+2.786X3+0.012X4+1.533X5。结论:子宫内膜异位症Ⅲ期-Ⅳ期、未接受促排卵治疗、高IL-1β、IL-18、TNF-α水平是育龄期女性子宫内膜异位症患者发生不孕症的危险因素,建立的Logistic回归模型可预测育龄期女性子宫内膜异位症患者发生不孕症的可能性,有助于帮助医务人员识别不孕症高风险者。 展开更多
关键词 子宫内膜异位症 育龄期女性 细胞因子 不孕症
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新技术在甘肃荒山植树造林中的应用
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作者 车宗奎 《园艺与种苗》 CAS 2024年第1期79-81,共3页
随着国家对荒山改造力度的逐渐增大,相关林业单位对采用新技术开展荒山植树造林工作越来越重视。该文以甘肃荒山植树造林为例,通过创新型植树造林技术有效改造荒山,逐步实现以生态化模式发展经济,从而加快黄河中上游流域生态环境修复工作。
关键词 甘肃地区 植树造林 荒山 应用
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荒山造林树种的选择与造林技术
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作者 杜海涛 《林业科技情报》 2024年第2期122-124,共3页
荒山造林地块交通不便,多为远山、高山和瘦山,立地条件较差,土壤瘠薄,不但是降水少、蒸发量大、日照时间短、负积温多,无霜期长,而且受干旱灾害频发,严重影响了造林的成活率低、保存率少。随着人们对生态环境的逐渐重视,荒山造林作为改... 荒山造林地块交通不便,多为远山、高山和瘦山,立地条件较差,土壤瘠薄,不但是降水少、蒸发量大、日照时间短、负积温多,无霜期长,而且受干旱灾害频发,严重影响了造林的成活率低、保存率少。随着人们对生态环境的逐渐重视,荒山造林作为改善生态环境的重要手段也愈发得到相应的重视。借助荒山造林的方式既可以带动当地经济良好发展,同时可以有效改善环境质量,进而创设优质的生活环境。对此该文主要从适地适树原则、生态优先原则、混交原则以及稳定原则等方面分析了荒山造林树种选择的基本原则,同时阐述了造林树种的具体选择,并对荒山造林技术进行了探讨,以供参考。 展开更多
关键词 荒山造林 基本原则 造林技术
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山西黄土丘陵区荒山造林技术研究
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作者 刘小鹏 《园艺与种苗》 CAS 2024年第1期48-50,共3页
为了改善山西省生态环境,实施对黄土丘陵区生态系统的全方位改造,加强荒山造林技术应用,攻克黄土丘陵区造林难题,对山西省黄土丘陵区荒山造林工作开展状况进行研究、整理和分析,阐述了山西省黄土丘陵区荒山造林面临的现实困境,从前期规... 为了改善山西省生态环境,实施对黄土丘陵区生态系统的全方位改造,加强荒山造林技术应用,攻克黄土丘陵区造林难题,对山西省黄土丘陵区荒山造林工作开展状况进行研究、整理和分析,阐述了山西省黄土丘陵区荒山造林面临的现实困境,从前期规划、整地、造林、抚育管理、日常养护等多个环节提出黄土丘陵区荒山造林技术应用优化策略,以重塑黄土丘陵区绿色生态,推动绿色发展战略目标实现,为相关工作人员提供理论参考。 展开更多
关键词 黄土丘陵区 荒山造林技术 应用研究
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Plant physiological changes along an encroachment gradient: an assessment of US Mid-Atlantic serpentine barrens
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作者 Nicole A.Havrilchak Jessica L.Schedlbauer 《Journal of Plant Ecology》 SCIE CSCD 2018年第6期853-865,共13页
Aims Serpentine barrens of the Mid-Atlantic United States are globally rare,grass-dominated ecosystems thought to exclude C3 spe-cies and characterized by unique soil composition.However,like many grassland ecosystems... Aims Serpentine barrens of the Mid-Atlantic United States are globally rare,grass-dominated ecosystems thought to exclude C3 spe-cies and characterized by unique soil composition.However,like many grassland ecosystems globally,these sites are presently facing encroachment by surrounding forest.In this ecosystem,the tendril climbing vine,Smilax rotundifolia,forms dense thickets around bar-rens that typically precede forest encroachment.While numerous factors speculatively initiate and promote encroachment in these systems,few studies have examined photosynthetic responses of serpentine grasses to changes in resource availability initiated by encroachers or physiological ability of encroaching S.rotundifolia to colonize high-light barren environments.We sought to under-stand both environmental and physiological dynamics of encroach-ment along an irradiance gradient in these systems.Methods At three serpentine barren sites in southeastern Pennsylvania,physiological responses of the native grasses Sorghastrum nutans and Schizachyrium scoparium to increased shading by S.rotundi-folia were examined.Additionally,the physiological performance of S.rotundifolia in the forest understory was compared to that in sunlit barrens environments.Light-saturated photosynthesis(A_(sat)),stomatal conductance(g_(s)),instantaneous transpiration efficiency(ITE),maximum efficiency of photosystem II(F_(v)/F_(m)),midday leaf water potential(ψ_(leaf))and specific leaf area(SLA)were measured for all species over the course of the 2014 growing season.Two-way analyses of variance were used to assess changes in these param-eters across growing environments,as well as seasonally for each species.Multiple regression analyses were also performed to inves-tigate the influence of vapor pressure deficit(D)and leaf tempera-ture(T_(leaf))on A_(sat) and ITE.Important Findings Light-saturated photosynthesis was significantly greater in S.rotun-difolia growing in sun than in the shade(P<0.001)and early in the season(P=0.012).Sun S.rotundifolia had up to 27%greater A_(sat) than shaded plants.Even with reducedψleaf in the barrens,S.rotundifolia maintained high g_(s) though A_(sat) was limited by high D later in the growing season.These data are in agreement with recent research suggesting that plants are not subject to water limi-tation in Mid-Atlantic barrens.Unexpectedly,shaded grasses at the encroachment interface did not exhibit any significant reduc-tion in A_(sat).Declines in grass photosynthesis do not likely occur until S.rotundifolia rhizomes transition into monotypic thickets,completely excluding grasses.Encroachment by S.rotundifolia appears to be primarily facilitated by its ability to capitalize on light resources early on in the summer growing season,when environ-mental conditions are less stressful. 展开更多
关键词 ENCROACHMENT PHOTOSYNTHESIS serpentine barren Schizachyrium scoparium Smilax rotundifolia Sorghastrum nutans
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Ga-(Nb+Ta)-(Nb/Ta)(Zr/Hf) Ternary Diagram: An Excellent Tool for Discriminating Barren and Ta-Hosting Granite-Pegmatite Systems
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作者 Maryam Mohamadizadeh Seyed Hossein Mojtahedzadeh Farimah Ayati 《Journal of Earth Science》 SCIE CAS CSCD 2020年第3期551-558,共8页
Discriminating barren and fertile intrusions is one of the main challenges in the search for rare-element pegmatites.Diagrams comprising more than one element can make discrimination of productive and barren samples m... Discriminating barren and fertile intrusions is one of the main challenges in the search for rare-element pegmatites.Diagrams comprising more than one element can make discrimination of productive and barren samples more valid.These diagrams distinguish samples by simultaneous means of positive and/or negative correlations between variables.A ternary diagram for S-type peraluminous granites has been obtained in this study.Firstly,a database composed of Ta-bearing and barren granitic systems was created,then geochemical behavior of trace elements was studied,and statistical investigations were done using GCDkit software,which resulted in the Ga-(Nb+Ta)-(Nb/Ta)(Zr/Hf)ternary diagram which can distinguish the non-mineralized granites from productive ones.The Ta-bearing samples,which are situated in the fertile field in the diagram,are those which have high Nb and Ta contents,elevated Ga content and the lowest Nb/Ta and Zr/Hf values. 展开更多
关键词 tantalum mineralization S-type peraluminous granite discrimination of fertile and barren granites whole-rock geochemistry indicators
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基于混合团树的贝叶斯网络智能推理算法 被引量:1
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作者 郑靓 孙毅 《东北师大学报(自然科学版)》 CAS 北大核心 2023年第2期35-44,共10页
提出了一种基于混合团树的智能推理体系架构,利用原始贝叶斯网络中变量之间的依赖关系对连接树进行改造,使得在推理过程中满足以下两个优势:(1)它能直接消除与证据和查询的无关的变量集,使得混合团树得以缩减为更小规模的二级树状结构,... 提出了一种基于混合团树的智能推理体系架构,利用原始贝叶斯网络中变量之间的依赖关系对连接树进行改造,使得在推理过程中满足以下两个优势:(1)它能直接消除与证据和查询的无关的变量集,使得混合团树得以缩减为更小规模的二级树状结构,进而使消息不必在所有节点中传播;(2)它继承了连接树传播算法中可以重复利用混合团树中预先储存的信息进行加速推理. 展开更多
关键词 贝叶斯网络 智能推理 连接树传播 混合团树 barren
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SART法和配合沉淀法脱除氰化贫液中铜氰的对比研究
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作者 刘强 伍赠玲 +3 位作者 高世康 王弘 韩良 林国钦 《湿法冶金》 CAS 北大核心 2023年第5期497-502,共6页
针对某黄金生产企业铜硫分离浮选后硫精矿氰化产生的氰化贫液,分别采用SART法与配合沉淀法净化处理,对比研究了2种方法的铜与氰化物的脱除效果及回收沉渣中铜、金的经济效益。结果表明:贫液中铜、金、氰化物和硫氰酸盐质量浓度分别为121... 针对某黄金生产企业铜硫分离浮选后硫精矿氰化产生的氰化贫液,分别采用SART法与配合沉淀法净化处理,对比研究了2种方法的铜与氰化物的脱除效果及回收沉渣中铜、金的经济效益。结果表明:贫液中铜、金、氰化物和硫氰酸盐质量浓度分别为121.46、0.12、150.84、252.65 mg/L时,采用SART法时在溶液pH=5、硫铜物质的量比2∶1条件下,滤液中铜、总氰化物质量浓度为1.52、99.72 mg/L,沉渣中铜、金质量分数分别为65.26%、10.56 g/t;采用配合沉淀法时,在铜离子与亚硫酸根物质的量比1.25∶1、铜离子与氰化物与硫氰酸盐之和物质的量比2∶1条件下,滤液中铜、总氰化物质量浓度为22.08、0.77 mg/L,沉渣中铜、金质量分数分别为51.26%、86.53 g/t;相较SART法,配合沉淀法回收有价金属经济效益更高,更适于回收含铜氰化贫液中的铜和氰化物。 展开更多
关键词 氰化贫液 SART法 配合沉淀法 净化 氰化物
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络合沉淀法净化处理铜氰贫液
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作者 刘强 伍赠玲 +3 位作者 高世康 王弘 韩良 林国钦 《矿冶》 CAS 2023年第6期88-95,共8页
针对某黄金生产企业产生的氰化贫液,采用络合沉淀法用复配亚铜溶液对贫液进行净化处理,考察初始pH值、硫酸铜与亚硫酸钠加药量对氰化物和铜离子去除效果的影响。采用BBD试验设计和响应面法建立贫液中氰化物和铜离子剩余含量的响应面方... 针对某黄金生产企业产生的氰化贫液,采用络合沉淀法用复配亚铜溶液对贫液进行净化处理,考察初始pH值、硫酸铜与亚硫酸钠加药量对氰化物和铜离子去除效果的影响。采用BBD试验设计和响应面法建立贫液中氰化物和铜离子剩余含量的响应面方程。通过对数学模型进行求解得知,在硫酸铜和亚硫酸钠投加量分别为3.01 g/L和2 g/L的条件下,处理后贫液中氰化物和铜离子浓度同时达到最低值,分别为0.38 mg/L和61.94 mg/L,响应面法的预测值与试验值吻合较好,所建模型的可信度较高。对处理后的贫液过滤后调节pH值至10,除去剩余的铜离子,铜离子、氰化物和硫氰酸盐浓度分别达到7.26、0.35和1.42 mg/L,达到回用于生产流程的条件要求。 展开更多
关键词 铜氰贫液 络合沉淀 净化处理 响应面法
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Single-qubit quantum classifier based on gradient-free optimization algorithm
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作者 张安琪 王可伦 +1 位作者 吴逸华 赵生妹 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期241-247,共7页
A single-qubit quantum classifier(SQC)based on a gradient-free optimization(GFO)algorithm,named the GFO-based SQC,is proposed to overcome the effects of barren plateaus caused by quantum devices.Here,a rotation gate R... A single-qubit quantum classifier(SQC)based on a gradient-free optimization(GFO)algorithm,named the GFO-based SQC,is proposed to overcome the effects of barren plateaus caused by quantum devices.Here,a rotation gate R_(X)(φ)is applied on the single-qubit binary quantum classifier,and the training data and parameters are loaded intoφin the form of vector multiplication.The cost function is decreased by finding the value of each parameter that yields the minimum expectation value of measuring the quantum circuit.The algorithm is performed iteratively for all parameters one by one until the cost function satisfies the stop condition.The proposed GFO-based SQC is demonstrated for classification tasks in Iris and MNIST datasets and compared with the Adam-based SQC and the quantum support vector machine(QSVM).Furthermore,the performance of the GFO-based SQC is discussed when the rotation gate in the quantum device is under different types of noise.The simulation results show that the GFO-based SQC can reach a high accuracy in reduced time.Additionally,the proposed GFO algorithm can quickly complete the training process of the SQC.Importantly,the GFO-based SQC has a good performance in noisy environments. 展开更多
关键词 single-qubit quantum classifier gradient-free parameters optimizing barren plateau quantum noise
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黄河源高寒草甸退化秃斑地土壤基本特征及其风蚀规律 被引量:1
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作者 童生春 李国荣 +5 位作者 李进芳 翟辉 朱海丽 刘亚斌 陈文婷 胡夏嵩 《水土保持研究》 CSCD 北大核心 2023年第4期10-17,共8页
[目的]阐明高寒草甸不同类型退化秃斑地的土壤基本特征及其风蚀规律,揭示土壤物理力学特性与土壤风蚀之间的交互影响作用,进而为黄河源区生态植被的修复和保护提供理论依据。[方法]以黄河源7种草甸退化秃斑地及高原鼢鼠鼠丘为研究对象,... [目的]阐明高寒草甸不同类型退化秃斑地的土壤基本特征及其风蚀规律,揭示土壤物理力学特性与土壤风蚀之间的交互影响作用,进而为黄河源区生态植被的修复和保护提供理论依据。[方法]以黄河源7种草甸退化秃斑地及高原鼢鼠鼠丘为研究对象,结合野外调查和原位试验,对不同秃斑地土壤物理力学特征、土壤风蚀规律的差异性及土壤风蚀量与可蚀性因子间的关联度和相关性等进行了分析和讨论。[结果](1)不同退化秃斑地土壤基本物理力学特性指标差异较显著,7种秃斑地的平均土壤含水率、密度、紧实度和黏聚力分别是高原鼢鼠鼠丘的1.3倍、2.6倍、14.2倍和5.0倍,秃斑地中风毛菊的恢复生长对土壤的保水固土能力最强,香薷草和臭蒿相对较弱。(2)风蚀60 min后高原鼢鼠鼠丘土壤的总流失量是退化秃斑地的1.3~4.4倍;风蚀量的增加幅度随风蚀时间呈先增后减的趋势,风蚀作用的前5~10 min是土壤风蚀的敏感期;不同退化秃斑地土壤风蚀量与植被恢复类型有关,且与土壤物理力学指标值之间呈反比例关系。(3)退化秃斑地土壤风蚀量与植被覆盖度、土壤含水率和土壤紧实度之间均呈线性负相关关系,与土壤黏聚力间呈指数函数负相关关系;土壤风蚀量与覆盖度、含水率、紧实度和黏聚力间存在极显著负相关,与土壤密度和土壤平均粒径分别存在显著负相关和显著正相关。[结论]不同类型的退化秃斑地均可通过提升土壤基本物理力学特性,从而对土壤风蚀产生抑制效应,其中风毛菊抑制效果最佳、香薷草和臭蒿相对较弱。 展开更多
关键词 黄河源区 高寒草甸 退化秃斑地 土壤基本特征 土壤风蚀
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元宝枫荒山造林技术研究 被引量:1
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作者 任红剑 程甜甜 +2 位作者 孙忠奎 张林 褚敏 《林业勘查设计》 2023年第3期9-13,共5页
针对全国局部地区荒山植被缺失和森林覆盖率较低的现状,结合大规模国土绿化行动,为充分利用树种资源、地类条件和气候等自然条件,课题组以山东省宁阳县为例,将元宝枫这一优良乡土树种应用于荒山造林,并进行技术研究,以期为元宝枫综合利... 针对全国局部地区荒山植被缺失和森林覆盖率较低的现状,结合大规模国土绿化行动,为充分利用树种资源、地类条件和气候等自然条件,课题组以山东省宁阳县为例,将元宝枫这一优良乡土树种应用于荒山造林,并进行技术研究,以期为元宝枫综合利用及森林环境改善提供技术支撑。 展开更多
关键词 元宝枫 荒山 造林技术 山东省宁阳县
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