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降水量变化及氮添加下荒漠草原土壤有机碳及其易分解组分研究

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植物生态学报 2024年第8期48卷 1065-1077页

作者：马煦晗黄菊莹余海龙韩翠李冰西北土地退化与生态恢复国家重点实验室培育基地西北退化生态系统恢复与重建教育部重点实验室宁夏大学生态环境学院银川750021 宁夏大学地理科学与规划学院银川750021

土壤有机碳(C)库在稳定陆地C循环和调节全球气候等方面扮演着重要角色。该研究基于2017年设立于宁夏荒漠草原的降水量变化(-50%、-30%、自然、+30%、+50%)及氮(N)添加(0和5 g·m-2·a-1)的两因素野外实验,探讨了处理4年后,0-60 cm土壤有... 详细信息

土壤有机碳(C)库在稳定陆地C循环和调节全球气候等方面扮演着重要角色。该研究基于2017年设立于宁夏荒漠草原的降水量变化(-50%、-30%、自然、+30%、+50%)及氮(N)添加(0和5 g·m-2·a-1)的两因素野外实验,探讨了处理4年后,0-60 cm土壤有机C特征(含量、储量、组分)的变化规律和影响因素,以期为科学预测全球变化下半干旱区草原C汇功能提供数据支撑。N添加对土壤有机C特征影响较小。相比之下,降水量改变了有机C特征,且其影响程度依赖于N水平和土层深度。就整个0-60 cm而言,与自然降水量相比,0 g·m-2·a-1 N添加下,增减降水量对有机C特征影响较小;5 g·m-2·a-1 N添加下,减少30%降水量显著提高了易氧化有机C和溶解性有机C含量,增加30%降水量显著提高了颗粒有机C和轻组有机C含量。有机C含量及其储量与土壤含水量、纤维二糖水解酶、碱性磷酸酶活性正相关,与土壤NO3--N含量负相关。易氧化有机C、颗粒有机C和轻组有机C含量与土壤亮氨酸氨基肽酶活性正相关,与微生物生物量N含量负相关。溶解性有机C和微生物生物量C含量则与以上3个指标呈相反的关系。研究结果表明,N添加下,降水量改变对土壤有机C含量及其储量影响较小,但适度增减降水量会通过改变土壤含水量、N有效性、酶活性以及植物群落优势度等途径降低有机C稳定性,从而导致荒漠草原土壤C排放风险增加。

关键词：半干旱区降水格局氮沉降土壤碳排放土壤碳稳定性

中国构建世界重要人才中心和创新高地的风险研究

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科学管理研究 2024年第3期42卷 136-143页

作者：韩彻驹张向前中南财经政法大学公共管理学院湖北武汉430073 上海应用技术大学人文学院上海201418

中国建设世界重要人才中心和创新高地需要防范化解重大风险。运用改进的耦合协调度模型评估构建人才中心与创新高地的系统性风险,基于人力资源管理环节和科技创新价值链分析主体性风险。研究发现,全国2015-2021年平均系统性风险指数均低... 详细信息

中国建设世界重要人才中心和创新高地需要防范化解重大风险。运用改进的耦合协调度模型评估构建人才中心与创新高地的系统性风险,基于人力资源管理环节和科技创新价值链分析主体性风险。研究发现,全国2015-2021年平均系统性风险指数均低于0.45,系统性风险整体稳定可控,但是需要加强防范三类人才安全风险和四类科技安全风险。中国应当建立包含情报收集、分析预警、防范处置三个部分的人才与科技安全风险治理体系;通过国内国际双循环格局的建设,深化人才培养与发展机制改革,构建高质量链式科技创新支撑体系,有利于提高创新效能。

关键词：人才中心创新高地科技创新风险管理

A typology of clustered housing for older adults towards opportunities for social interaction:A case study of Dutch social housing

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Frontiers of Architectural Research 2024年第3期13卷 561-574页

作者： kim Hamers Nienke Moor Masi Mohammadi Research Group Architecture in Health HAN University of Applied SciencesArnhemthe Netherlands Chair Smart Architectural Technologies Eindhoven University of TechnologyEindhoventhe Netherlands

Dutch housing associations are dealing with a growing number of tenants who are ageing in ***,there is a lack of suitable housing that meets the(social)needs of this target *** housing,which offers a socio-spatial context that facilitates encounters between residents,is considered a promising housing concept to(partly)fill this ***,clustered housing is a broad concept consisting of a variety of housing types that differ from each other in the extent to which people“live together”.Still little is known about which types of clustered housing can be distinguished in relation to the potential for social ***,in this article we distinguish between types of clustered housing based on social,organizational,and spatial building *** have mapped these characteristics by combining real estate data of housing association Woonzorg Nederland with survey data collected among their building *** on this dataset,an explorative cluster analysis was performed,resulting in four types of clustered ***,further exploration of the data shows that,from the perspective of building managers,residents of certain types of clustered housing interact more often and feel more connected with each other than residents of non-clustered housing types.

关键词： Clustered housing Typology Seniors Social housing

Effect of Radiant Spectral Characteristics on Performance of a Near-Infra-Red Heating Module

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Journal of Thermal Science 2011年第6期20卷 510-515页

作者： ju-Hyun kim Won-Taek Choi Minsub han School of Mechanical System Engineering University of Incheon Araytech IncheonKorea

We simulated the heat transfer phenomena of the heating module that is primarily based on the radiant energy in the near-infra-red(NIR) *** the module,the power emitted by the lamp filament is distributed to the lamp glass,reflector,and the target medium,which are cooled by an air *** radiant heat transfer is simulated by using the ray-tracing scheme,in which the spectral characteristics of the emission and the materials are *** heat transport from the lamp glass to the cooling air is analyzed by using the finite volume *** the lamp-filament temperature rises in the range of 3000-3400K,the NIR radiant power on the target medium ***,the lamp-glass temperature also rises,and the proportion of the NIR power to the entire radiation has a peak in the temperature *** spectral distributions of the absorbed energies in all the components in the module are highly non-uniform,and a monochromatic model of the radiant heat transfer may result in a significant discrepancy.

关键词： Computational Fluid Dynamics(CFD) Curing Drying Coating process

基于大型无人机航磁全轴梯度测量技术研究与应用

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地球物理学报 2024年第8期67卷 3162-3172页

作者：郭华鞠星韩松王萌王明李冰梁韧中国自然资源航空物探遥感中心北京100086

目前,我国航空物探在远海地区和青藏高原地区的工作程度并不高,这主要是由于我国现有有人机航空物探飞行平台的续航里程不够远或者无法在高海拔地区开展大比例尺、低高度飞行测量工作.由于彩虹4无人机的续航时间达到20余小时,飞行高度可... 详细信息

目前,我国航空物探在远海地区和青藏高原地区的工作程度并不高,这主要是由于我国现有有人机航空物探飞行平台的续航里程不够远或者无法在高海拔地区开展大比例尺、低高度飞行测量工作.由于彩虹4无人机的续航时间达到20余小时,飞行高度可达7300 m,经过项目研制,基于彩虹4无人机航磁全轴梯度测量系统突破了探测装置的集成设计、磁干扰特性的优化提升等一系列关键技术,首次实现了基于无人机的航磁总场、横向梯度、垂直梯度的一站式测量,航磁总场补偿后标准差优于±30 pT,横向梯度补偿后标准差优于±2 pT/m,垂向梯度补偿后标准差优于±6 pT/m,达到同类测量系统的国际领先水平,大大提升了我国在艰难地区和远海地区的勘查能力.

关键词：大型无人机航磁全轴梯度横向梯度垂向梯度

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Influence of overhanging tool length and vibrator material on electromechanical impedance and amplitude prediction in ultrasonic spindle vibrator

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 292-310页

作者： Rendi KURNIAWAN Moran XU Min Ki CHOO Shuo CHEN Yein KWAK' Jielin CHEN Saood ALI hanwei TENG Pil Wan han Gi Soo kim Tae Jo KO Precision Machining Laboratory Department of Mechanical Engineering Yeungnam UniversityGyeongsansiGyeongbuk-doRepublic of Korea Korea Electrotechnology Research Institute(KERI) ChangwonsiGyeongsangnam-doRepublic of Korea KASWIN Co. LtdChangwon-siGyeongsangnamdoRepublic of Korea

This study presents the development of an ultrasonic transducer with a radius horn for an ultrasonic milling spindle(UMS)*** ultrasonic transducer was intended to have a working frequency of approximately 30 *** different materials were considered in the study:stainless steel(SS 316L)and titanium alloy(Ti-6Al-4V).Titanium alloy gave a higher resonance frequency(33 kHz)than stainless steel(30 kHz)under the same preload compression *** electromechanical impedance simulation was carried out to predict the impedance resonance frequency for both materials,and the effect of the overhanging toolbar was *** to the electromechanical impedance simulation,the overhanging toolbar length affected the resonance frequency,and the error was less than 3%.Harmonic analysis confirmed that the damping ratio helps determine the resonance ***,damping ratios of 0.015-0.020 and 0.005-0.020 were selected for stainless steel and titanium alloy,respectively,with an error of less than 1.5%.Experimental machining was also performed to assess the feasibility of ultrasonic-assisted milling;the result was a lesser cutting force and better surface topography of Al 6061.

关键词： Ultrasonic spindle Ultrasonic vibration assisted-milling(UVAM) 1-degree of freedom(DOF) Frequency Amplitude Milling

Solar‑Driven Sustainability:Ⅲ–ⅤSemiconductor for Green Energy Production Technologies

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Nano-Micro Letters 2024年第11期16卷 445-478页

作者： Chandran Bagavath Jeong‑Kyun Oh Sang‑Wook Lee Dae‑Young Um Sung‑Un kim Veeramuthu Vignesh Jin‑Seo Park Shuo han Cheul‑Ro Lee Yong‑Ho Ra Division of Advanced Materials Engineering Engineering CollegeResearch Center for Advanced Materials Development(RCAMD)Jeonbuk National UniversityJeonju 54896Republic of Korea

Long-term societal prosperity depends on addressing the world’s energy and environmental problems,and photocatalysis has emerged as a viable *** the efficiency of photocatalytic processes is fundamentally achieved by optimizing the effective utilization of solar energy and enhancing the efficient separation of photogenerated *** has been demonstrated that the fabrication ofⅢ–Ⅴsemiconductor-based photocatalysts is effective in increasing solar light absorption,long-term stability,large-scale production and promoting charge *** focused review explores on the current developments inⅢ–Ⅴsemiconductor materials for solar-powered photocatalytic *** review explores on various subjects,including the advancement ofⅢ–Ⅴsemiconductors,photocatalytic mechanisms,and their uses in H2 conversion,CO_(2)reduction,environmental remediation,and photocatalytic oxidation and reduction *** order to design heterostructures,the review delves into basic concepts including solar light absorption and effective charge *** also highlights significant advancements in green energy systems for water splitting,emphasizing the significance of establishing eco-friendly systems for CO_(2)reduction and hydrogen *** main purpose is to produce hydrogen through sustainable and ecologically friendly energy *** review intends to foster the development of greener and more sustainable energy source by encouraging researchers and developers to focus on practical applications and advancements in solar-powered photocatalysis.

关键词： Green energy system Hydrogen evolution CO_(2)reduction Ⅲ-Ⅴsemiconductors Photo electrochemical water splitting

Optimal sequential therapy using tyrosine kinase inhibitors as the first-line treatment in patients with metastatic renal cell carcinoma: A nationwide multicenter study

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Asian Journal of Urology 2024年第3期11卷 450-459页

作者： jung Ki Jo Seong Il Seo MinYong Kang Jinsoo Chung Cheol Kwak Sung-Hoo Hong Cheryn Song Jae Young Park Chang Wook Jeong Seok Hwan Choi Sung han kim Eu Chang Hwang Chan Ho Lee Hakmin Lee Department of Urology Medical and Digital EngineeringCollege of MedicineHanyang UniversitySeoulRepublic of Korea Department of Urology Samsung Medical CenterSungkyunkwan University School of MedicineSeoulRepublic of Korea Department of Urology National Cancer CenterGoyangRepublic of Korea Department of Urology Seoul National University HospitalSeoulRepublic of Korea Department of Urology Kangnam St Mary’s HospitalSeoulRepublic of Korea Department of Urology Asan Medical CenterSeoulRepublic of Korea Department of Urology Korea University Ansan HospitalAnsanRepublic of Korea Department of Urology Kyungpook National University HospitalDaeguRepublic of Korea Department of Urology Chonnam National University Hwasun HospitalHwasunRepublic of Korea Department of Urology Inje University Busan Paik HospitalBusanRepublic of Korea Department of Urology Seoul National University Bundang HospitalSeongnamRepublic of Korea

Objective:The purpose of the study was to identify the best sequence of therapy beginning with a tyrosine kinase inhibitor(TKI)as the first-line therapy for patients with metastatic renal cell carcinoma(mRCC)in terms of overall survival(OS),progression-free survival(PFS),and rates of discontinuation and adverse effects during the treatment ***:This is a retrospective,nationwide multicenter study of patients with mRCC after diagnosis at 10 different tertiary medical centers in Korea from January 1992 to December *** focused on patients at either“favorable”or“intermediate”risk according to the International mRCC Database Consortium criteria,and they were followed up(median 335 days).Finally,a total of 1409 patients were selected as the study *** generated a Cox proportional hazard model adjusted for covariates,and the different therapy schemes were statistically tested in terms of OS as well as *** addition,frequencies of discontinuation and adverse events were compared among the therapy ***:Of the primary patterns of treatment sequences(24 sequences),“sunitinib epazopanib”and“sunitinibeeverolimuseimmunotherapy”showed the most beneficial results in both OS and PFS with significantly lower hazards than“sunitinib”,which is the most commonly treated agent in *** that the“TKIeTKI”structure showed relatively higher discontinuation rates with higher adverse effects,the overall beneficial sequence would be“sunitinibeeverolimuseimmunotherapy”.Conclusion:Among several sequential therapy starting with TKIs,“sunitinibeeverolimuse immunotherapy”was found to be the best scheme for mRCC patients with“favorable”or“intermediate”risks.

关键词： Tyrosinekinase inhibitor Metastaticrenalcell carcinoma Overall survival Progression-free survival

All-fiber acousto-optic modulator based on a cladding-etched optical fiber for active mode-locking

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Photonics Research 2017年第5期5卷 391-395页

作者： JIHWAN kim JOONHOI KOO ju han LEE School of Electrical and Computer Engineering University of Seoul

An all-fiber acousto-optic modulator(AOM), which features a compact structure and a low-driving voltage, is experimentally demonstrated for the active mode-locking of a fiber laser. The proposed AOM is based on the short length of the cladding-etched fiber, the ends of which are fixed on a slide glass. On top of the cladding-etched fiber, a piezoelectric transducer was overlaid. A chemical wet-etching technique, which is based on a mixed solution of NH_4F and (NH_4)2SO_4, is used to reduce the fiber diameter down to ～25 μm, and the length of the etched section is only 0.5 cm. The fabricated device exhibited a modulation depth of 73.10% at an acoustic frequency of 918.9 kHz and a peak-to-peak electrical voltage of 10 V, while a laser beam was coupled at 1560 *** using the prepared AOM within an erbium-doped-fiber ring cavity, the mode-locked pulses with a temporalwidth of 2.66 ps were readily obtained at a repetition rate of 1.838 MHz.

关键词： All-fiber acousto-optic modulator based on a cladding-etched optical fiber for active mode-locking