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Prim.ry and Secondary m.croplastic and Nanoplastic Regulations: Perspectives on Water Industry Im.acts

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Journal of environm.0}tal Protection 2024年第6期15卷 697-715页

作者： Shirin Estahbanati Giridhar Upadhyaya m.rtha J. m. Wells Katherine Y. Bell Brown and Caldwell New York NY USA Brown and Caldwell Irvine CA USA enviroChem.Services Cookeville TN USA Brown and Caldwell Nashville TN USA

Plastic pollution, both prim.ry and secondary, is an environm.0}tal challenge, prom.ting regulatory actions at global and regional levels. With increasing research about the im.acts of m.cro- and nanoplastics on ecosystem. and hum.n health, governm.0}ts worldwide have undertaken efforts to address this issue. The global com.unity has advanced regulatory efforts that have led to the im.lem.0}tation of national laws or regulations in num.rous countries. These m.asures ban or restrict the use of prim.ry and secondary m.croplastics and nanoplastics. An overview of global and European regulatory fram.works is presented to provide context for the United States (US). In the endeavor to docum.0}t plastics regulation developm.0}t in the US, a description of regulatory agencies and their roles in advancing policy and rules as well as future direction and areas for im.rovem.0}t in regulating plastics are introduced. A discussion of what em.rging regulations m.an to utilities and industries is also provided along with a com.arison of regulatory fram.works.

关键词： m.croplastic Regulation environm.0}tal Governance Plastic Pollution m.tigation Regulatory Fram.work

农业社会化服务试点政策的碳减排效果评估——来自准自然实验的证据

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长江流域资源与环境 2024年第9期33卷 1918-1928页

作者：周发明唐望彭柳林湖南农业大学经济学院湖南长沙410128 湖南第一师范学院商学院湖南长沙410205 江西省农业科学院农业经济与信息研究所江西南昌330200

全球温室效应引发的极端天气给农业生产造成了巨大损失,有效降低农业碳排放强度成为各国政府和学者关注的热点话题。运用渐进双重差分法等从政策效应出发探讨了农业社会化服务试点政策的碳减排效应、影响机制和异质性。研究结果表明:(1... 详细信息

全球温室效应引发的极端天气给农业生产造成了巨大损失,有效降低农业碳排放强度成为各国政府和学者关注的热点话题。运用渐进双重差分法等从政策效应出发探讨了农业社会化服务试点政策的碳减排效应、影响机制和异质性。研究结果表明:(1)农业社会化服务试点政策实施对农业碳排放强度具有持续的抑制作用,能有效实现农业碳减排。在一系列稳健性检验后模型的结果依旧是稳健的。(2)农业社会化服务试点政策实施可以通过降低化肥施用强度、促进土地流转和促进种植结构“趋粮化”调整来间接降低农业碳排放强度。(3)农业社会化服务试点政策的碳减排效果存在异质性,其中在农业碳排放强度较高的地区、粮食主产区和非西部地区,政策的碳减排效果更显著。因此,为有效降低农业碳排放强度,需要稳步促进土地流转,加快建立完善的农业生产社会化服务体系,加大政策支持与构建激励机制并举,全面响应化肥农药减量化行动,推进农业绿色社会化服务水平提升。

关键词：农业社会化服务试点政策农业碳排放强度政策效应评价准自然实验渐进双重差分法

Design of 1.9 GHz RF Cm.S VCO

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The Journal of China Universities of Posts and Telecom.unications 2009年第3期16卷 103-107页

作者： LI en-ling WANG Xue SONG Lin-hong YUAN Yong-xia YU fa-da LIU m.n-cang School of Sciences XJ'an University of Technology Xi'an 710048 China

A voltage controlled oscillator （VCO） m.dule is designed, which can be used for the third generation m.bile com.unication （3G） system. The circuit is sim.lated by spectre radio frequency （RF） by TSm. 0.25 μm.Cm.S process. During the sim.lation, the perform.nce param.ters of the designed VCO are as follows： tuning range 1.804 GHz-2.039 GHz, phase noise - 136.457 dBc/Hz @1 m.z, - 146.045 dBc/Hz@3 m.z, supply voltage 2.5 V, voltage output rate of 0.8 V-2.6 V, power consum.tion 25 roW. The layout of the related circuit is drawn by the Virtuoso Layout Editor.

关键词： LC voltage controlled oscillator on-chip inductor on-chip varactor phase noise

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喀斯特栎类老龄林的空间结构分析

林业科学研究 2024年第2期37卷 104-114页

作者：骆秀琼何吉安李远发广西大学林学院广西森林生态与保育重点实验室广西南宁530004 来宾金秀大瑶山森林生态系统广西野外科学观测研究站广西来宾545700

[目的]研究喀斯特栎类老龄林的分布格局、空间关联和标记特征,探明垂直分层在喀斯特森林生物多样性维系中的作用。[方法]在中国西南地区南盘江流域的喀斯特老龄林(>300 a)中建立1块面积为200 m.110 m.固定样地,依据树高和物种组分将... 详细信息

[目的]研究喀斯特栎类老龄林的分布格局、空间关联和标记特征,探明垂直分层在喀斯特森林生物多样性维系中的作用。[方法]在中国西南地区南盘江流域的喀斯特老龄林(>300 a)中建立1块面积为200 m.110 m.固定样地,依据树高和物种组分将树木划分为林分上层和林分下层,用负指数函数分析了径阶与物种多度和丰富度的数量关系,用双相关函数g(r)分析林分上层、林分下层以及它们各自主要种群的分布格局和空间关联,用标记相关函数km.(r)分析树种和树木大小的空间分布。[结果](1)林分、林分上层和林分下层的径阶分布均呈倒J型,林分和林分下层的物种丰富度随径阶的增大而减小,而林分上层则呈先升后降的趋势;(2)林分上层在多数尺度上呈规则或随机分布,仅在小尺度(r=0~1 m.4~6 m.上表现为聚集分布,林分下层的聚集强度和尺度皆大于林分上层;(3)林分上层和林分下层之间,以及它们各自的主要种群之间均以随机关联为主,只有个别种间对在小尺度(r=0~2 m.上呈正关联或负关联;(4)林分和林分下层在所有观测尺度上表现为同种聚集,强度明显大于林分上层;林分和林分上层的个体大小分化明显,小径木聚集。林分下层的个体大小相近,在多数尺度上混生。[结论]垂直分层决定了林分上层、林分下层的物种组分、多度、分布格局和空间关联,在物种共存和多样性维持中扮演重要角色。

关键词：喀斯特老龄林垂直分层大小分化分布格局

Calcium.titanate corrosion inhibitor enabling carbon as inert anode for oxygen evolution in m.lten chlorides

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Transactions of Nonferrous m.tals Society of China 2024年第10期34卷 3400-3411页

作者： Kai-fa DU Wen-m.ao LI Pei-lin WANG Lei GUO Di CHen Yong-song m. Rui YU Hua-yi YIN Di-hua WANG School of Resource and environm.0}tal Sciences Wuhan UniversityWuhan 430072China Hubei International Scientific and Technological Cooperation Base of Sustainable Resources and energy Wuhan 430072China

The corrosion inhibition efficacy of titanate(CaTiO_(3))for carbon anodes in m.lten salts was investigated through various analytical techniques,including linear sweep voltam.etry,X-ray diffraction,scanning electron m.croscopy,and energy dispersion *** results dem.nstrate that the addition of CaTiO_(3)corrosion inhibitor efficiently passivates the carbon anode and leads to the form.tion of a dense CaTiO_(3)layer during the electrolysis process in m.lten CaCl_(2)-***,the passivated carbon anode effectively undergoes the oxygen evolution reaction,with an optim.l current density for passivation identified at 400 m.A/cm.*** investigations,including CaTiO_(3)solubility tests in m.lten CaCl_(2)-CaO and num.rical m.deling of the stability of com.lex ionic structures,provide com.elling evidence supporting“com.lexation-precipitation”passivation *** m.chanism.involves the initial form.tion of a com.lex containing TiO_(2)·nCaO by CaTiO_(3)and CaO,which subsequently decom.oses to yield CaTiO_(3),firm.y coating the surface of the carbon *** practical applications,the integration of CaTiO_(3)corrosion inhibitor with the carbon anode leads to the successful preparation of the FeCoNiCrm. high-entropy alloy without carbon contam.nation in the m.lten CaCl_(2)-Ca O.

关键词： corrosion inhibitor calcium.titanate carbon anode oxygen evolution reaction

Vegetation Change Prediction with Geo-Inform.tion Techniques in the Three Gorges Area of China

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Pedosphere 2006年第4期16卷 457-467页

作者： m. T. JABBAR SHI Zhi-Hua WANG Tian-Wei CAI Chong-fa Huazhong Agriculture University Wuhan 430070 （China）. Departm.0}t-of Soil and Water College of Agriculture University of Basrah （Iraq）

A com.uterized param.tric m.thodology was applied to m.nitor, m.p, and estim.te vegetation change in com.ination with '3S' (RS-rem.te sensing, GIS-geographic inform.tion system., and GPS-global positioning system. technology and change detection techniques at a 1:50000 m.pping scale in the Letianxi Watershed of western Hubei Province, China. Satellite im.ges (Landsat Tm.1997 and Landsat ETm.2002) and them.tic m.ps were used to provide com.rehensive views of surface conditions such as vegetation cover and land use change. With ER m.pper and ERDAS software, the norm.3}zed difference vegetation index (NDVI) was com.uted and then classified into six vegetation density classes. ARC/INFO and ArcView software were used along with field observation data by GPS for analysis. Results obtained using spatial analysis m.thods showed that NDVI was a valuable first cut indicator for vegetation and land use system.. A regression analysis revealed that NDVI explained 94.5% of the variations for vegetation cover in the largest vegetation area, indicating that the relationship between vegetation and NDVI was not a sim.le linear process. Vegetation cover increased in four of areas. This m.ant 60.9% of land area had very slight to slight vegetation change, while 39.1% had m.derate to severe vegetation change. Thus, the study area, in general, was exposed to a high risk of vegetation cover change.

关键词： geo-inform.tion techniques vegetation change vegetation indices

Radiological findings of February 2023 twin earthquakes-related spine injuries

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World Journal of Radiology 2024年第9期16卷 398-406页

作者： Ayşenur Bolukçu Ahm.t Gürkan Erdem.r İlkay Sedakatİdilm.n Adalet Elçin Yildiz GökçenÇobanÇifçi m.hm.t Ruhi Onur Erhan Akpinar Departm.0}t of Radiology Hacettepe UniversityFaculty of MedicineAnkara 06100Türkiye Departm.0}t of Radiology University of ChicagoChicagoIL 60637United States

BACKGROUND The February 6,2023,twin earthquakes in Türkiye caused significant structural dam.ge and a high num.er of injuries,particularly affecting the spine,which underscores the im.ortance of understanding the distribution and nature of vertebral injuries in disaster *** To investigate the distribution of radiological findings of vertebral injuries in patients referred to a m.jor tertiary center during the February 6,2023 twin earthquakes in Tü*** With the approval of the institutional ethics com.ittee,1216 exam.nations of 238 patients transferred from.the region to a tertiary m.jor hospital after the twin earthquakes of February 6,2023,were retrospectively analyzed for spine *** Spine com.uted tom.graphy(CT)scans were perform.d in 192 of 238 patients with a suspected spinal injury,42 of whom.also had an m.gnetic resonance im.ging(m.I).In 86 of 192 patients(44.79%;m.F=33:53)a spinal fracture was detected on CT and in 33 of 42 patients(78.57%;m.F=20:13)a spinal injury was found on *** the 86 patients in whom.vertebral injury was detected,fractures were detected in the Denis-B group in 33,Denis-C in 4,Denis-D in 20 and Denis-E in 11 *** the vertebral bodies:40"com.ression fractures",17"burst fractures",5"translational dislocation fractures",5"flexion-distraction fractures"and 58"prolonged forced fetal posture fractures"were *** addition,isolated transverse or spinous process fractures were found in eighteen *** Our study highlights the prevalence and diverse spectrum.of spinal injuries following the February 6,2023 twin earthquakes in Turkey underscoring the urgent need for effective m.nagem.0}t strategies in sim.lar disaster scenarios,and em.hasizing the"prolonged forced fetal posture"dam.ge we encountered in earthquake victim. who rem.ined under the collapse for a long tim..

关键词： Accidental injuries Com.ression fractures Crush injuries Earthquakes Spine

Europium.recovery process by m.ans of polym.ric nanoparticles functionalized with acrylic acid,curcum.n and fum.ram.de

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Journal of Rare Earths 2024年第10期42卷 1950-1959页

作者： P.A.m.rtínez-m.ntoya J.m.del Río A.de J.m.rales-Ram.rez m.Corea Escuela Superior de Ingeniería Quím.ca e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.Lindavista Escuela Superior de Ingenieria Quím.ca e Industrias Extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.Lindavista Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/n

Polym.ric nanoparticles of poly(m.thyl m.thacrylate) were obtained by em.lsion polym.rization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcum.n,and fum.ram.de and three series of polym.ric particles were *** incorporation of functional groups was confirm.d by Fourier transform.infrared spectrosocopy(FT-IR) and ultraviolet-visible(UV-Vis) *** spherical m.rphology of particles with an average diam.ter of 100 nm.was observed by scartning electron m.croscopy(SEm..The polym.ric m.terials were used for recovery of [Eu]from.synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover m.re than 85% of [Eu] at pH of *** im.ges of SEm.after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50% of it,m.intaining their hom.geneity in m.rphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second m.del order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of6.

关键词： Chelating effect Em.lsion polym.rization Extraction process Rare earths Stripping process [Eu]recovery

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广告点击率预估的逐层残差交互网络

计算机学报 2024年第3期47卷 575-588页

作者：尹云飞龙连杰黄发良吴开贵重庆大学计算机学院重庆400044 广西人机交互与智能决策重点实验室南宁530100

网络广告费的收取通常是以用户的点击次数来计算的,因此如何准确地预估点击率(CTR)是广告公司十分关心的问题.当前先进水平的方法集中在构建各种高阶特征交互模型来预估CTR,但是高阶特征交互会丢失低阶信息,尤其是丢失原始特征的信息.为... 详细信息

网络广告费的收取通常是以用户的点击次数来计算的,因此如何准确地预估点击率(CTR)是广告公司十分关心的问题.当前先进水平的方法集中在构建各种高阶特征交互模型来预估CTR,但是高阶特征交互会丢失低阶信息,尤其是丢失原始特征的信息.为此,本文提出一个新的逐层残差交互网络,它在每次交互时都考虑原始特征的引导作用,被命名为逐层残差交互网(LRIN).LRIN强调高阶特征交互应该建立在原始特征逐层交互的基础上.n阶特征交互由原始特征与n-1阶特征通过元素积运算得到.进而,本文引入了多尺度方法来设计注意力网络.受逐层交互的影响,注意力网络也被设计成多层,称之为逐层注意力网络.为了将二者结合起来,本文提出将逐层残差交互网络的输出作为逐层注意力网络的权重,由此形成了一种新的双网络训练模型.在多个benchm.rk数据集上的实验结果表明,LRIN的性能比当前先进的方法在Criteo数据集上平均提高1.24%,在Avazu数据集上平均提高2.16%,在m.vieLens-1m.据集上平均提高了1.3%,在Book-Crossing数据集上平均提高了1.27%.

关键词：残差网络逐层特征交互 CTR预估注意力