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基于整合分析土壤微生物量碳、氮含量对有机肥施用的响应特征

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中国土壤与肥料 2024年第6期 89-101页

作者：莫艳芳申云鑫贺彪施竹凤唐加菜杨童雨翟恒韩天华陈齐斌杨佩文云南省农业科学院农业环境资源研究所云南昆明650205 云南农业大学植物保护学院云南昆明650201 云南省烟草公司丽江市公司云南丽江674100

土壤微生物量碳、氮含量是评价土壤肥力的重要指标。探究施用有机肥对土壤微生物量碳、氮含量的影响,旨在为生产中有机肥的科学施用提供指导。通过数据库共检索得高质量文献84篇,提取有效田间试验数据625组,以不施肥和单施无机肥为对照... 详细信息

土壤微生物量碳、氮含量是评价土壤肥力的重要指标。探究施用有机肥对土壤微生物量碳、氮含量的影响,旨在为生产中有机肥的科学施用提供指导。通过数据库共检索得高质量文献84篇,提取有效田间试验数据625组,以不施肥和单施无机肥为对照,采用Meta分析有机肥施用下土壤微生物量碳、氮含量和作物产量变化及其影响因素。研究结果表明:施用有机肥对土壤微生物量碳、氮含量以及作物产量具有显著的促进作用(P<0.05),分别增加41.14%[95%置信区间(CI):38.32%~44.04%]、46.46%(95%CI:43.02%~50.01%)和48.85%(95%CI:43.86%~45.03%)。与不施肥相比,施用有机肥可提高微生物量碳含量46.80%(95%CI:43.22%~50.46%),提高微生物量氮含量56.0%(95%CI:47.18%~65.37%),提高作物产量47.48%(95%CI:39.98%~55.36%);与单施化肥相比,有机肥施用下土壤微生物量碳含量可提高36.06%(95%CI:21.22%~52.71%),微生物量氮含量可提高40.80%(95%CI:30.42%~52.01%),作物产量可提高4.04%(95%CI:2.26%~5.46%);Meta分析结果表明,土壤微生物量碳、氮含量以及作物产量还受作物类型、氮肥施用量、有机肥施用方式、土壤初始pH、土壤类型以及气候条件的影响。进一步相关性分析结果表明,微生物量碳含量与土壤初始pH和年均温度呈显著正相关(P<0.05);土壤微生物量氮含量与土壤初始pH和氮肥施用量呈显著正相关(P<0.05);土壤微生物量碳氮比与年均温度呈显著正相关(P<0.05);作物产量与土壤微生物量碳、氮含量和土壤初始pH呈显著正相关(P<0.05)。有机肥对土壤微生物量碳、氮含量及作物产量具有显著的促进作用,建议结合作物类型、土壤条件和气候类型等因素,构建单施或配施有机肥的施肥技术,实现构建土壤健康微生态,最终实现肥料资源有效利用和提高土壤生产力的目的。

关键词：微生物量碳微生物量氮有机肥土壤肥力作物产量 Meta分析

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Application and prospective of 3D printing in rock mechanics: A review

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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 1-17页

作者： Yong-tao Gao tian-hua Wu Yu Zhou Key Laboratory of Ministry for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

This review aims to discuss the application and development of three-dimensional printing(3DP) technology in the field of rock mechanics and the mechanical behaviors of 3D-printed specimens on the basis of various available printing *** review begins with a brief description of the concepts and principles associated with 3DP, and then systematically elaborates the five major applications of 3DP technology in the field of rock mechanics, namely, the preparation of rock(including pre-flawed rock) specimens, preparation of joints, preparation of geophysical models, reconstruction of complex rock structures, and performance of bridging experimental testing and numerical ***, the mechanical performance of 3D-printed specimens created using six different printing materials, such as polymers, resin,gypsum, sand, ceramics, and rock-like geological materials, is reviewed in ***, some improvements that can make these 3D-printed specimens close to natural rocks and some limitations of 3DP technology in the application of rock mechanics are *** prospects that are required to be investigated in the future are also ***, a brief summary is *** review suggests that 3DP technology, especially when integrated with other advanced technologies, such as computed tomography scanning and 3D scanning, has great potential in rock mechanics field.

关键词： three-dimensional printing(3DP) rock mechanics 3DP material rock analogue 3DP geotechnical model numerical simulation

Heat transfer characteristics for double-jet in different flow regions on a thick plate

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Journal of Iron and Steel Research International 2021年第11期28卷 1400-1407页

作者： Xiu-hua tian tian-liang Fu Zhao-dong Wang Guo-dong Wang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

During multi-jet cooling,the complex hydrodynamic characteristics caused by the interaction between jets will affect the heat transfer of the *** further clarify the heat transfer characteristics in different flow regions,the double-jet cooling experiments were completed on a 50-mm-thick plate with the initial cooling temperature and jet angle in the range of 300–900°C and 0°–60°,*** inverse heat conduction was used to calculate the surface temperature and heat ***,the rewetting phenomenon,maximum heat flux and maximum cooling speed were *** results show that increasing the angle between jet and wall normal would increase the wetting front’s width downstream of the jet *** the jet angle was 60°,the maximum value increased by 37.29 mm compared with that when the angle was *** correlation between the width of the wetting front and the radial temperature gradient was further *** addition,it was found that the maximum heat flux would be affected by the duration of transition boiling,but not affected by complete wetting *** results clarified the heat transfer mechanisms under various initial cooling temperature and inclination angle conditions on plate cooling in different flow regions,and provided valuable data for controlling heat transfer efficiency and improving cooling uniformity.

关键词： Double-jet Thick plate Rewetting phenomenon Flow region Heat flux

Physicochemical and environmental characteristics of alkali leaching residue of wolframite and process for valuable metals recovery

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Transactions of Nonferrous Metals Society of China 2022年第5期32卷 1638-1649页

作者： Yuan-lin CHEN Xue-yi GUO Qin-meng WANG Qing-hua tian Jin-xiang ZHANG Shao-bo huaNG School of Metallurgy and Environment Central South UniversityChangsha 410083China Ganzhou Nonferrous Metallurgy Research Institute Ganzhou 341000China Changsha Research Institute of Mining and Metallurgy Co. LTDChangsha 410012China

Physicochemical and mineralogical characteristics of an alkali leaching residue of wolframite were studied by XRD,SEM−EDS,chemical phase analysis,mineral liberation analyzer(MLA),and TG−DSC *** leaching tests,toxicity characteristic leaching procedure(TCLP)tests and Chinese standard leaching tests(CSLT)were conducted to determine the environmental mobility of toxic *** results show that,due to the high contents of W,Fe,Mn,Sn,and Nb,the residue is with high resource value,but the content of a toxic element,As,is also *** existing minerals of the investigated elements mainly occur as monomer particles,but it is difficult to extract these valuable metals by conventional acid leaching due to their mineral *** release of As increases over time in acidic *** leaching concentration of all investigated harmful elements through TCLP is within the limiting value,while the leaching concentration of As through CSLT exceeds the limiting value by more than 4 times,so the residue is classified as hazardous solid waste based on the Chinese standard.A process for valuable metals recovery from this residue was *** experimental results indicated that the main valuable metals could be extracted effectively.

关键词： alkali leaching residue physicochemical characteristics environmental characteristics valuable metals recovery

Controversies about the use of serological markers indiagnosis of in flammatory bowel disease

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World Journal of Gastroenterology 2010年第2期16卷 279-280页

作者： Xie, Qin Gan, hua-tian Sichuan Univ Dept Geriatr W China Hosp Chengdu 610041 Sichuan Peoples R China Sichuan Univ Dept Gastroenterol W China Hosp Chengdu 610041 Sichuan Peoples R China

The serological markers are increasingly used in diagnosis of inflammatory bowel disease(IBD).D-lactate and diamine oxidase are new indicators that can be used to reveal the damage to intestinal mucosa and permeability alteration in *** the two biological markers seem more sensitive,recent clinical trials and animal experiments have shown controversies about the use of them in diagnosis of ***, these markers should be interpreted cautiously and further prospective studies are needed to establish their clinical role in diagnosis of IBD.

关键词： Inflammatory bowel diseases D-lactate Diamine oxidase Intestinal permeability Diagnosis

Effect of Al content in molten steel on interaction between MgO-C refractory and SPHC steel

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Journal of Iron and Steel Research International 2024年第4期31卷 838-848页

作者： Fu-bin Gao Fu-ming Wang Xiang Zhang tian-yu Du Xin-hua Wangg School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Handan Iron and Steel Company Hegang GroupHandan 056015HebeiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The effect of Al content in molten steel on the interaction between SPHC steel(0.005-0.068 wt.%Al,and 19×10^(-4)-58×10^(-4)wt.%O)and MgO-C refractory(11.63 wt.%C)was ***-metallic inclusions in the steel were examined at various periods(0,5,15,30,45,and 60 min)as well as the MgO-C interface after 60 min of corrosion at 1600℃.The results show that when MgO-C refractory comes into contact with SPHC steel,the refractory interface consists of three layers arranged from the innermost to the outermost,including the original refractory layer,the dense MgO layer,and the iron infiltration *** carbon in the MgO-C refractories and the Al content in the molten steel undergo a reaction with the MgO in the refractories,resulting in an increase in Mg concentration in the *** Al content in the molten steel from 0.005 to 0.068 wt.%causes a spinel layer to appear at the interface,and the disappearance time of Al_(2)O_(3) inclusions in the steel decreases from 60 to 30 min,while the average MgO content in inclusions ***,controlling the Al content in the molten steel and the smelting duration can help regulate the formation of spinel inclusionsinthe steel.

关键词： MgO-C refractory SPHC steel Inclusion-Spinel Al-killed steel Interfacial reaction

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机器人辅助人工髋膝关节置换手术是必然趋势

中华医学杂志 2022年第1期102卷 4-8页

作者：田华北京大学第三医院骨科骨与关节精准医学教育部工程研究中心北京100191

人工髋、膝关节置换是骨科领域最成功的手术之一,能有效缓解疼痛、矫正畸形和改善功能,从而提高患者整体生活质量。尽管髋、膝关节置换是目前治疗晚期髋、膝疾患的常规手术,但依然存在着术后肢体不等长、脱位或不稳定、跛行和不明原因... 详细信息

人工髋、膝关节置换是骨科领域最成功的手术之一,能有效缓解疼痛、矫正畸形和改善功能,从而提高患者整体生活质量。尽管髋、膝关节置换是目前治疗晚期髋、膝疾患的常规手术,但依然存在着术后肢体不等长、脱位或不稳定、跛行和不明原因疼痛等并发症。这些并发症的发生很大程度上与假体安放的位置相关。机器人辅助进行髋、膝关节置换手术的优势不仅在于术前可进行三维手术规划,而且手术过程中机械臂能够辅助完美实现术前规划,避免了人为误差。目前的关节置换机器人依然存在着不能进行个性化手术规划、手术时间长效率低、价格昂贵等问题,但相信在人工智能加持和算法的不断优化下,人工关节置换机器人将会越来越精准化、智能化和微创化,这是关节外科未来发展的必然趋势。

关键词：关节成形术机器人辅助手术髋关节置换术膝关节置换术

抛光色选工艺过程对香稻米2-AP含量和糊化特性的影响

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中国稻米 2024年第4期30卷 53-55,63页

作者：杜晓旭张莹莹何珍珍刘剑涛莫钊文潘圣刚田华段美洋祁剑英唐湘如华南农业大学亚热带农业生物资源保护与利用国家重点实验室/农业农村部华南地区作物栽培科学观测实验站/广州市丝苗香米科学与技术重点实验室广州510642

抛光色选工序是生产食用大米的重要步骤,会影响稻米品质和香气2-乙酰基-1-吡咯啉(2-AP)含量。以香稻品种19香和软华优金丝为材料,研究了工业生产中抛光色选工艺过程对香米2-AP含量和糊化特性的影响。结果表明,在稻米抛光阶段增加抛光色... 详细信息

抛光色选工序是生产食用大米的重要步骤,会影响稻米品质和香气2-乙酰基-1-吡咯啉(2-AP)含量。以香稻品种19香和软华优金丝为材料,研究了工业生产中抛光色选工艺过程对香米2-AP含量和糊化特性的影响。结果表明,在稻米抛光阶段增加抛光色选程序会导致19香和软华优金丝2-AP含量分别损失51.66%和38.10%,蛋白质含量分别降低7.31%和1.49%,水分含量、淀粉峰值黏度、最低黏度、最终黏度和消减值都有上升,而回冷值降低。

关键词：香稻抛光品质 2-乙酰基-1-吡咯啉淀粉糊化特性

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Clinicopathological characteristics and prognosis of gastric signet ring cell carcinoma

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World Journal of Clinical Cases 2022年第29期10卷 10451-10466页

作者： hua-Kai tian Zuo Zhang Zhi-Kun Ning Jiang Liu Zi-Tao Liu Hao-Yu huang Zhen Zong Hui Li Department of General Surgery First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Obstetrics and Gynecology Second Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Day Ward First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Gastrointestinal Surgery Second Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Rheumatology and Immunology First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND The clinicopathological features and prognosis of gastric signet ring cell carcinoma(GSRC)remain controversial,particularly with regard to sensitivity to postoperative adjuvant *** To compare the pathological features of GSRC with those of gastric adenocarcinoma of different degrees of differentiation and the differences in survival prognosis between the different disease *** By screening gastric cancer patients from 2010 to 2015 in the database of Surveillance,Epidemiology and End Results,and collecting the clinicopathological and prognostic data of gastric cancer patients who underwent surgery from January 2014 to December 2016 in the Second Affiliated Hospital of Nanchang University,we analyzed the general pathological characteristics of GSRC by the chi-square *** and multivariate analyses were conducted to compare the factors affecting the survival and prognosis of early and advanced gastric *** Kaplan-Meier curves were plotted to reveal the survival difference between early and advanced GSRC and different differentiated types of gastric *** prognosis model of advanced GSRC was established with R software,and the area under curve(AUC)and C-index were used to assess the accuracy of the *** Analysis of pathological features revealed that signet ring-cell carcinoma(SRC)was more frequently seen in younger(5 cm(31.15%vs 27.10%)compared to the differentiated type,while the opposite was true compared to the undifferentiated *** prognostic analysis found no significant difference in the prognosis of SRC patients among EGC *** contrast,among advanced gastric cancer(AGC)patients,the prognosis of SRC patients was correlated with age,race,tumour size,AJCC stage,T-stage,and postop

关键词： Gastric adenocarcinoma Gastric signet ring cell carcinoma Pathological features Survival prognosis Prognostic model Adjuvant therapy