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Recovering indium with sulfating roasting from copper-smelting ash

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Rare Metals 2007年第5期26卷 488-491页

作者： ZHU Guocai zheng mingdan FAN Guanglong ZHAO Yuna Institute of Nuclear and New Energy Technology Tsinghua University Beijing 102201 China

A technology for recovering indium from Jinchuan copper-smelting ash was developed. Indium in the ash was first enriched to the leaching-slag in leaching process,and then recovered by sulfating roasting. The method included mixing the leaching-slag with sulfuric acid,making them into particles,roasting the mixture,and then leaching the calcine with hot water. Above 90% of indium in calcine could be dissolved into the leaching solution. The optimized conditions were determined as follows： the mass ratio of sulfuric acid to leaching slag was 0.1,the roasting time was about 1 to 1.5 h in the temperature range of 200-250℃,and the calcine was leached for 1 h with 5：1 of liquid/solid ratio at 60℃. Over 99% of indium in leaching solution was finally enriched by Zn substitution or sulfide precipitation.

关键词： environmental engineering indium roasting copper-smelting ash

基于车载激光LiDAR点云数据的路面坑槽自动提取方法研究

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测绘与空间地理信息 2024年第10期47卷 197-199,203页

作者：郑明丹孙五斌罗明生浙江省测绘科学技术研究院浙江杭州311100

以车载激光LiDAR扫描道路点云数据为研究对象,提出一种基于点云剖面特征描述的坑槽提取方法。首先,对原始点云数据进行滤波处理,获取地面点数据;其次,对道路横纵剖面进行道格拉斯-普克算法的轮廓拟合,将积分不变性与微分特征作为描述算... 详细信息

以车载激光LiDAR扫描道路点云数据为研究对象,提出一种基于点云剖面特征描述的坑槽提取方法。首先,对原始点云数据进行滤波处理,获取地面点数据;其次,对道路横纵剖面进行道格拉斯-普克算法的轮廓拟合,将积分不变性与微分特征作为描述算法进行坑槽提取;最后,使用约束条件进行点云聚类实现噪声点的剔除,进一步识别确定提取坑槽。为了验证本文方法的有效性,使用某段道路点云数据进行实验,结果表明,本文方法能够有效提取得到道路面坑槽点,不受坑槽形状的限制,具有较高的精度。

关键词：车载激光LiDAR 点云滤波坑槽特征描述

Long-term thinning decreases the contribution of heterotrophic respiration to soil respiration in subalpine plantations

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Journal of Forestry Research 2024年第3期35卷 189-204页

作者： Longfei Chen Zhibin He Wenzhi Zhao Xi Zhu Qin Shen mingdan Song zhengpeng Li Junqia Kong Shuping Yang Yuan Gao Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China State Forestry Administration Key Laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China Academy of Agriculture and Forestry Sciences Qinghai UniversityXining 810000People's Republic of China College of Landscape Architecture Zhejiang A&F UniversityHangzhou 310000People's Republic of China

Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental ***,as a principal silvicultural practice,the long-term impacts of thinning on R_(S) and its heterotrophic and autotrophic respiration components(R_(h) and Ra,respectively)in subalpine plantations are poorly understood,espe-cially in winter.A 3-year field observation was carried out with consideration of winter CO_(2) efflux in middle-aged sub-alpine spruce plantations in northwestern China.A trench-ing method was used to explore the long-term impacts of thinning on Rs,Rn and R_(a).Seventeen years after thinning,mean annual Rs,Rn and R_(a) increased,while the contribu-tion of R_(h) to R_(s) decreased with thinning *** significantly decreased winter R,because of the reduction in R_(n) but had no significant effect on *** temperature sensitivity(Q_(10))of R_(h) and R_(a) also increased with thinning intensity,with lower Q_(10) values for R_(h)(2.1-2.6)than for Ra(2.4-2.8).The results revealed the explanatory variables and pathways related to R_(n) and R_(a) *** increased soil moisture and nitrate nitrogen(NO_(3)^(-)-N),and the enhanced nitrogen and water availability promoted R_(h) and R_(a) by improving fine root biomass and microbial *** results highlight the positive roles of NO_(3)^(-)-N in stimulating R_(s) components following long-term ***,applications of nitrogen fertilizer are not recommended while thinning subalpine spruce plantations from the perspective of reducing soil CO_(2) *** increased Q_(10) values of R_(s) components indicate that a large increase in soil CO_(2) emissions would be expected following thinning because of more pronounced climate warming in alpineregions.

关键词： Heterotrophic respiration Autotrophic respiration Long-term thinning impacts Cold seasons Subalpine plantations Temperature sensitivity

L2, 1-Norm Regularized Matrix Completion for Attack Detection in Collaborative Filtering Recommender Systems

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Chinese Journal of Electronics 2019年第5期28卷 906-915页

作者： SI mingdan LI Qingshan School of Computer Science and Technology Xidian University

Collaborative filtering recommender systems(CFRSs) are known to be highly vulnerable to profile injection attacks, in which malicious users insert fake profiles into the rating database in order to bias the systems' output, since their openness, and attack detection is still a challenging problem in CFRSs. In order to provide more accurate recommendations, many schemas have been proposed to detect such shilling ***, almost all of them are proposed to detect one or several specific attack types, and few of them can handle hybrid attack types, which usually happen in practice. With this problem in mind, we propose a novel L2, 1-norm regularized matrix completion incorporating prior information(LRMCPI) model to detect shilling attacks by combining matrix completion and L2, *** proposed LRMCPI formalizes the attack detection problem as a missing value estimation problem, and it is appropriate because the user-item rating matrix is approximately low-rank and attack profiles could be considered as structural noise. The proposed LRMCPI model not only can better recover the rating matrix using correct rating value but also can detect the positions where the attackers are injected. We evaluate our model on three well-known data sets with different density and the experimental results show that our model outperforms baseline algorithms in both single and hybrid attack types.

关键词： Profile injection attacks Shilling attacks Attack detection L2,1-norm Matrix completion

基于DNDC模型长期复种翻压绿肥对土壤有机碳和小麦产量的模拟

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草业科学 2024年第2期41卷 332-344页

作者：肖玉涛李正鹏宋明丹段豆豆韩梅青海大学农林科学院青海西宁810016

对青海高原农田特有春小麦(Triticum aestivum)+豆科绿肥栽培模式,为揭示绿肥还田对于春小麦产量和土壤有机碳(SOC)的长期效应,本研究采用小区试验与模型相结合的方法探索适宜青海高原的绿肥还田方式。本研究采用裂区试验设计,主区为秋... 详细信息

对青海高原农田特有春小麦(Triticum aestivum)+豆科绿肥栽培模式,为揭示绿肥还田对于春小麦产量和土壤有机碳(SOC)的长期效应,本研究采用小区试验与模型相结合的方法探索适宜青海高原的绿肥还田方式。本研究采用裂区试验设计,主区为秋闲期复种绿肥翻压还田(G)和不种绿肥不还田(CK),副区为后茬春小麦化肥用量,设置100%常规施肥(F_(100),225 kg·hm^(-2)N、112.5 kg·hm^(-2)P_(2)O_(5))、70%常规施肥(F_(70),157.5 kg·hm^(-2)N、78.75 kg·hm^(-2)P_(2)O_(5))和不施化肥(F_(0)),共6个处理,基于2019-2022年的田间试验数据对反硝化-分解(DNDC)模型进行率定与验证,用验证过的模型对不同处理下土壤有机碳和小麦产量的长期变化规律进行模拟研究。结果表明:DNDC模型可以较好地模拟土壤有机碳和小麦产量,率定和验证过程中土壤有机碳模拟值和实测值的NRMSE值介于0.017-0.295,R^(2)介于0.763-0.924,小麦产量模拟值和实测值的NRSME值范围为0.160-0.280,R^(2)均大于0.75,表明模拟值和实测值具有一致性,可以用校准验证过的模型模拟0-50 cm土层土壤SOC和小麦产量;未来30年的模拟结果显示,绿肥翻压还田可以增加土壤SOC,具体表现为F_(70)+G>F_(100)+G>F_(0)+G>F_(100)> F_(70)> F_(0);0-50 cm土层土壤SOC储量30年变化依次为172.82、136.91、65.21、-35.61、-46.70和-143.95kg·hm^(-2),产量趋势为F_(70)+G>F_(100)+>G>F_(100)>F_(70)>F_(0)+G>F_(0),绿肥翻压还田配施化肥增产效果较好,F_(0)+G、F_(70)+G和F_(100)+G比无绿肥处理(F_(0)、F_(70)、F_(100))下小麦产量分别提高了85.7%、87.5%和20.0%;模拟的土壤有机碳含量和小麦产量具有一定的相关性。综合来看,长期复种绿肥翻压还田配施70%的化肥的固碳增产效果最佳。

关键词：毛叶苕子绿肥还田春小麦模型评价模拟预测施氮量有机碳

冠心病合并焦虑抑郁的中医病因病机及治疗的研究进展

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中国医药导报 2024年第3期21卷 64-67页

作者：姚曳朱明丹天津中医药大学第二附属医院心内科天津300250

焦虑抑郁常与心血管系统疾病合并发生,对患者身心健康与生活质量都造成不利影响。本文基于中医整体观念、辨证论治的思维核心,对冠心病合并焦虑抑郁临床常见的病因病机、辨证治法进行分析,通过梳理归纳近年来临床治疗中运用到的中药汤... 详细信息

焦虑抑郁常与心血管系统疾病合并发生,对患者身心健康与生活质量都造成不利影响。本文基于中医整体观念、辨证论治的思维核心,对冠心病合并焦虑抑郁临床常见的病因病机、辨证治法进行分析,通过梳理归纳近年来临床治疗中运用到的中药汤剂、针灸推拿及其他中医特色疗法,探究中医治疗冠心病合并焦虑抑郁的处方规律。中医治疗冠心病合并焦虑抑郁具有效果明确、形式多样、易于接受、副作用小等优势,值得进一步与临床基础治疗结合,共同襄助患者向愈。

关键词：冠心病焦虑抑郁中医病因病机中医治疗

Bond valence parameters linearly dependent on the molybdenum oxidation states

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Chinese Science Bulletin 2002年第12期47卷 978-981页

作者： mingdan Chen Zhaohui Zhou Shengzhi Hu Xiamen Univ Dept Chem Inst Chem Phys State Key Lab Phys Chem Solid Surfaces Xiamen 361005 Peoples R China

Based on the available crystal data, a linear correlation between R0, the bond valence parameter for a Mo-containing chemical bond, and the Mo oxidation state n was developed for the first time. Using the 'universal' value of the parameter B = 0.037 nm, the linear equations of R0-n for Mo-X (X: O, S, N, Cl and F) bonds were established. The oxidation-state independent Mo-O bond valence parameters, R0 = 0.18788 nm and B = 0.03046 nm, published recently have been shown to be a special case of the linearly correlated functions. Some bond valence sum calculations in compounds containing only Mo-O bonds using these parameters are presented.

关键词： bond valence parameter Mo-O bond oxidation state valence sum rule.

基于降低便秘副作用的碳酸钙D_(3)咀嚼片制剂处方优化的研究

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医学临床研究 2024年第7期41卷 964-968页

作者：李明丹刘理谢宇圆朱恒陈志湖南省药物安全评价研究中心&新药药效与安全性评价湖南省重点实验室&长沙市儿科用药研究技术创新中心湖南长沙410329

【目的】探讨基于降低便秘副作用的碳酸钙D_(3)咀嚼片制剂处方优化方法。【方法】通过文献调研不同辅料对小鼠小肠运动的影响,选取5种不同辅料组成的市售产品,根据市售产品辅料组成实验室自制2种成品,通过小鼠小肠运动实验筛选出最优辅... 详细信息

【目的】探讨基于降低便秘副作用的碳酸钙D_(3)咀嚼片制剂处方优化方法。【方法】通过文献调研不同辅料对小鼠小肠运动的影响,选取5种不同辅料组成的市售产品,根据市售产品辅料组成实验室自制2种成品,通过小鼠小肠运动实验筛选出最优辅料组成。ICR小鼠随机分为8组,即空白对照组、401自制组、601自制组、金贝牌市售品组及已上市产品1组、2组、3组、4组,每组20只,雌雄各半,各组分别进行单次给药实验(给药1次)、重复给药实验(给药30 d),给药组给药剂量均为130 mg/kg(按钙含量计算),空白对照组给予相同体积纯水。实验期间每天观察小鼠一般表现和粪便性状;重复给药实验每周收集各组小鼠粪便,观察、拍照各组小鼠粪便性状,称各组6 h内粪便重量;单次给药实验、重复给药实验均在末次给药后进行肠推进实验,计算小鼠小肠墨汁推进率。【结果】不同辅料组成的碳酸钙D_(3)咀嚼片单次给药对小鼠小肠推进率均未见明显影响。重复给药30 d,与空白对照组比较,601自制组及已上市产品1组、2组、3组、4组小鼠可见粪便干燥,墨汁推进率明显降低(P<0.05);601自制组及已上市产品3组、4组小鼠给药3周、4周时粪便重量及已上市产品1组、2组小鼠给药4周粪便重量均明显减少(P<0.05);401自制组、金贝牌市售品组小鼠粪便性状、小肠推进率、粪便重量均未见明显影响。【结论】辅料组成中含有促排便成分的碳酸钙D_(3)咀嚼片可降低重复给药引起的便秘,不同促排便机制辅料可协同发挥作用,经过本研究比较,专利产品金贝牌碳酸钙D_(3)咀嚼片(浙江寰领科技有限公司,专利号CN112972408A)处方工艺最优,可有效降低重复给药引起的便秘。

关键词：便秘碳酸钙药用制剂

Comparison in diversity of eukaryotic algae in surface sediments from different functional sea areas of Qingdao coast,the Yellow Sea,China:a metabarcoding approach

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Journal of Oceanology and Limnology 2022年第6期40卷 2322-2342页

作者： Zhaohui WANG mingdan LEI Shuanghui JI Changliang XIE Jiazhuo CHEN Weiguo LI Tao JIANG College of Life Science and Technology Jinan UniversityGuangzhou 510632China Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of EducationGuangzhou 510632China School of Ocean Yantai UniversityYantai 264005China

Surface sediment samples were collected in three different functional sea areas in Qingdao coast,East China,including the inner Jiaozhou Bay,the Laoshan Coast,and the Amphioxus Reserve *** and community structure of eukaryotic algae especially those of phytoplankton resting stages were assessed by metabarcoding V4 region of the 18S *** elements including total organic carbon(TOC),organic matter(OM),total nitrogen(TN),total phosphorus(TP),and biogenic silicon(BSi)were analyzed.A total of 1496 eukaryotic operational taxonomic units(OTUs)were measured,including 207algal OTUs,which contributed to 13.84%of the total ***-eight species in 8 phyla,24 classes of eukaryotic algae were *** them,47 species have been reported to form resting stages,and 12 species are firstly recorded in Chinese coastal *** agellates dominated in both DNA reads and OTU richness,which contributed to 73.02%and 61.35%of the eukaryotic algal sequences and OTU richness,*** reads,OTU richness and alpha diversity indexes of eukaryotic algae were higher in the Laoshan Coast,and lower in Jiaozhou *** algal community differed in the three sea areas,which was dominated by chrysophytes in Jiaozhou Bay,by dinofl agellates in the Laoshan Coast,and co-dominated by dinoflagellates and chrysophytes in the Amphioxus Reserve *** analysis showed that the Laoshan Coast and the Amphioxus Reserve area are clustered together,while Jiaozhou Bay is clustered ***-six harmful algal bloom(HAB)species were detected,and 10 species have been reported to form blooms in Jiaozhou Bay and the Qingdao coast *** of these species occurred widely and dominantly in this study,suggesting high potential risk of HABs in the Qingdao coastal area.

关键词： benthic microalgae 18S rDNA metabarcoding resting stages Jiaozhou Bay Yellow Sea