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蔬菜根系土壤硒镉含量与理化性质关系研究

北方园艺 2024年第12期 66-72页

作者：王丽蒋亚王迎康刘桂华柴冠群范成五贵州省农业科学院土壤肥料研究所贵州贵阳550006 观山湖区农业农村局贵州贵阳550081

以贵州省观山湖区土壤-蔬菜协同样为试材,采用调查采样方法,研究了蔬菜硒镉、土壤硒镉含量及主要理化性质,进一步了解蔬菜硒镉富集情况,明确主要土壤理化指标与土壤硒镉含量的关系,以期为富硒土壤资源的综合利用提供参考依据。结果表明... 详细信息

以贵州省观山湖区土壤-蔬菜协同样为试材,采用调查采样方法,研究了蔬菜硒镉、土壤硒镉含量及主要理化性质,进一步了解蔬菜硒镉富集情况,明确主要土壤理化指标与土壤硒镉含量的关系,以期为富硒土壤资源的综合利用提供参考依据。结果表明:在各级理化性质分级下,土壤(0~20 cm)全硒平均含量均高于富硒土壤标准(0.4 mg·kg^(-1));采集的46件蔬菜样品镉含量均未超过食品安全国家标准《食品中污染物限量》(GB2762-2022)限量值,超标率为0%,镉的安全性较高,硒含量均未检出。土壤理化性质对硒、镉的地球化学行为有重要影响,土壤有机质、pH、碱解氮与土壤硒含量呈显著相关关系,土壤速效钾与土壤镉含量呈极显著相关关系,土壤有机质、pH、碱解氮与土壤硒之间分别呈幂函数、指数函数、线性函数关系,土壤速效钾与土壤镉含量之间呈线性函数关系。研究区存在“土壤富硒作物不富硒”的问题,究其原因是土壤总硒与有效硒的关系不明确,因此在今后的研究中探究土壤中硒的形态特征及生物有效性对富硒农产品的稳定生产具有重要意义。

关键词：土壤蔬菜全硒全镉理化性质

基于改进斑点鬣狗算法的并网型微电网优化调度

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宁夏电力 2024年第4期 56-62页

作者：刘胜范成武鲁偎依李巧玲国网湖北省电力有限公司黄石供电公司湖北黄石435000 国网湖北省电力有限公司随州供电公司湖北随州441300

为了实现并网型微电网的经济运行,提出了一种基于改进斑点鬣狗(improved spotted hyena optimization, ISHO)算法的并网型微电网优化调度方法。以微电源维护成本、柴油机发电成本和购售电成本组成微电网调度成本,构建了以微电网调度成... 详细信息

为了实现并网型微电网的经济运行,提出了一种基于改进斑点鬣狗(improved spotted hyena optimization, ISHO)算法的并网型微电网优化调度方法。以微电源维护成本、柴油机发电成本和购售电成本组成微电网调度成本,构建了以微电网调度成本最小为目标函数的并网型微电网调度模型。采用Logistic映射、非线性递减控制参量和反向学习等策略对斑点鬣狗(spotted hyena optimization, SHO)算法进行改进,获得ISHO算法。采用ISHO算法对并网型微电网调度模型进行求解,并将优化结果与其他算法进行对比分析,结果表明,ISHO算法获得的最低调度成本为3 575.25元,相比其他几种对比算法的求解精度更高,验证了ISHO算法在微电网优化调度方面的有效性。

关键词：并网型微电网优化调度改进斑点鬣狗算法调度成本

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贵州青黄泥田重金属元素低积累水稻品种筛选

中国稻米 2024年第1期30卷 75-83页

作者：张容慧张秀锦柴冠群范成五何腾兵秦松贵州大学农学院贵阳550025 贵州大学新农村发展研究院贵阳550025 贵州民族大学贵阳550025 贵州省农业科学院土壤与肥料研究所贵阳550025

以贵州中部地区近年主栽的10个水稻品种为试验材料,在中轻度重金属复合污染农田土壤上开展田间原位小区试验,探究不同水稻品种对镉(Cd)、铬(Cr)、铅(Pb)、镍(Ni)、铜(Cu)和锌(Zn)的吸收累积能力差异,并筛选出适宜贵州中部青黄泥田种植... 详细信息

以贵州中部地区近年主栽的10个水稻品种为试验材料,在中轻度重金属复合污染农田土壤上开展田间原位小区试验,探究不同水稻品种对镉(Cd)、铬(Cr)、铅(Pb)、镍(Ni)、铜(Cu)和锌(Zn)的吸收累积能力差异,并筛选出适宜贵州中部青黄泥田种植的重金属低累积水稻品种。结果表明,不同水稻品种根区土壤重金属含量存在一定的田间异质性,且同一品种的重复之间也具有一定的田间异质性;不同水稻品种糙米对不同重金属元素累积具有显著性差异,参试水稻品种糙米对重金属的富集能力强弱整体表现为Zn>Cd>Cr>Cu>Ni>Pb。水稻品种间对同一典型有害重金属元素的累积存在显著差异,按照糙米中重金属含量进行聚类分析,可以把水稻品种划分为较高值类、中间值类和较低值类3个类别。10个水稻品种糙米综合污染指数(P_(Z))(0.94~3.34)介于无污染至重度污染之间,Cr为主要污染贡献者,其单项污染指数(P_(i))在0.47~1.94之间。供试水稻品种产量在8242.8~13434.0 kg/hm^(2)之间,平均产量为10843.8 kg/hm^(2),极差相差较大,为47.9%。筛选出宜香优800为适宜该地种植的重金属低积累水稻品种。

关键词：水稻重金属低累积品种产量青黄泥田贵州

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不同生育期喷施硒肥对白菜硒镉吸收影响研究

中国农学通报 2024年第11期40卷 44-48页

作者：王丽蒋亚刘桂华柴冠群范成五贵州省农业科学院土壤肥料研究所贵阳550006

为探究不同生育期喷施硒(Se)肥对白菜Se和镉(Cd)吸收的影响。通过田间试验,研究不同生育期喷施Se肥对Cd污染土壤白菜固Cd增Se及对外源Se利用指数的影响。结果表明:白菜幼苗期+莲座期+结球期(YM+LZ+JQ)喷施Se肥白菜地上部生物量显著高于... 详细信息

为探究不同生育期喷施硒(Se)肥对白菜Se和镉(Cd)吸收的影响。通过田间试验,研究不同生育期喷施Se肥对Cd污染土壤白菜固Cd增Se及对外源Se利用指数的影响。结果表明:白菜幼苗期+莲座期+结球期(YM+LZ+JQ)喷施Se肥白菜地上部生物量显著高于其他喷施时期;不同生育期喷施Se肥均可降低白菜地上部和地下部Cd含量,在白菜苗期+莲座期+结球期连续喷施Se肥降Cd效果较为明显,同时白菜地上部、地下部Se含量显著高于其他喷施时期;白菜苗期+莲座期+结球期连续喷施Se肥白菜外源Se利用指数为2.63,显著高于其他喷施时期。综上,在白菜幼苗期+莲座期+结球期喷施Se肥降Cd增Se效果较好。

关键词：镉白菜生育期硒肥外源硒利用指数

A progressive framework for rotary motion deblurring

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Defence Technology（防务技术） 2024年第2期32卷 159-172页

作者： Jinhui Qin Yong Ma Jun Huang fan fan You Du School of Electronic Information Wuhan UniversityWuhan430072China

The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating *** rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur *** solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement *** the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details *** a novel deconvolution model is proposed based on BE *** the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling *** establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur *** results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur *** code and dataset are available at https://***/JinhuiQin/RotaryDeblurring.

关键词： Rotary motion deblurring Progressive framework Blur extents factor TDM-CNN

Optimization of microstructure design for enhanced sensing performance in flexible piezoresistive sensors

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Journal of Advanced Ceramics 2024年第6期13卷 711-728页

作者： Xinghao fan Hailong Hu Bin Liao Yaqi Zhang fan Zhang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Research Institute of Aerospace Technology Central South UniversityChangsha 410083China

Flexible piezoresistive strain sensors have received significant attention due to their diverse applications in monitoring human activities and health,as well as in robotics,prosthetics,and human–computer interaction *** the various flexible sensor types,those with microstructure designs are considered promising for strain sensing due to their simple structure,high sensitivity,extensive operational range,rapid response time,and robust *** review provides a concise overview of recent advancements in flexible piezoresistive sensors based on microstructure design for enhanced strain sensing performance,including the impact of microstructure on sensing mechanisms,classification of microstructure designs,fabrication methods,and practical ***,this review delves into the analysis of piezoresistive sensor sensing mechanisms and performance parameters,exploring the relationship between microstructure design and performance ***,an in-depth discussion is presented,focusing on the primary themes of microstructure design classification,process selection,performance characteristics,and specific *** review employs mathematical modeling and hierarchical analysis to emphasize the directionality of different microstructures on performance enhancement and to highlight the performance advantages and applicable features of various microstructure *** conclusion,this review examines the multifunctionality of flexible piezoresistive sensors based on microstructure design and addresses the challenges that still need to be overcome and improved,such as achieving a wide range of stretchability,high sensitivity,and robust *** review summarizes the research directions for enhancing sensing performance through microstructure design,aiming to assist in the advancement of flexible piezoresistive sensors.

关键词： microstructure design sensing performance flexible piezoresistive strain sensors microsensing mechanism

Impact of non-ideal UE hardware on cell-free massive MIMO network with centralized operation

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Science China(Information Sciences) 2024年第4期67卷 255-271页

作者： Ning LI Pingzhi fan Institute of Mobile Communications Southwest Jiaotong University

This paper investigates the impact of non-ideal user equipment(UE) hardware on a cell-free(CF) massive MIMO(mMIMO) network with centralized operation under spatially correlated channels. The minimum mean-squared error(MMSE) estimator can be derived with the help of the generic non-ideal UE hardware model. It is demonstrated that even if the effective signal-to-noise ratio approaches infinity, pilot contamination and imperfect hardware can cause a non-zero estimation error floor. After that, a lower bound is determined for the ergodic uplink capacity of the centralized CF mMIMO network under non-ideal UE hardware. Moreover, the optimal receive combining vector is obtained to maximize the uplink spectral efficiency(SE). The maximum ratio(MR) and regularized zero-forcing(RZF) combining schemes are offered as alternatives in light of the computational complexity of the MMSE receiver. Comparing the RZF to the MMSE scheme under different levels of hardware impairments, our findings indicate that the RZF receiver suffers a negligible loss in total SE. For MR combining, a novel closed-form uplink achievable SE expression is obtained based on the MMSE estimator and the use-and-then-forget bounding technique. This expression gives vital insights into the achievable uplink performance with UE hardware impairments. Besides, for various hardware impairment factors, the impact of pilot sequence length on average sum SE is disclosed for different receive combining schemes. To increase the overall SE of the max-min fairness scheme, a heuristic fractional power control scheme with UE hardware impairments is developed, which can essentially avoid sacrificing the SE of other UEs while maximizing the SE of the unluckiest UE in the whole network. Finally,our theoretical performance analysis and power control algorithm are validated by simulation results, and fundamental design guidelines are provided for selecting hardware satisfying the practical UE requirements.

关键词： cell-free massive MIMO centralized operation spatially correlated channels hardware impairments channel estimation uplink spectral efficiency optimal receive combining pilot length design fractional power control

Semi-analytical Solutions for Wellbores with Graded Skin Zones in Poroelastic Media

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Acta Mechanica Solida Sinica 2024年第3期37卷 385-395页

作者： Zhiqiang fan Zhihe Jin School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Department of Mechanical Engineering University of MaineOronoME04469USA

In analyzing the complex interaction between the wellbore and the reservoir formation,the hydromechanical properties of the region proximal to the wellbore,referred to as the“wellbore skin zone”,play a pivotal role in determining flow dynamics and the resulting formation *** models of the wellbore skin zone generally assume a constant permeability throughout,resulting in a sharp permeability discontinuity at the skin-reservoir *** paper introduces a model for a wellbore with a continuously graded skin zone of finite thickness within a poroelastic *** solutions are derived using the Laplace transform method,addressing both positive and negative skin *** results are presented to illustrate the effects of graded permeability/skin zone thickness on pore pressures and stresses around a *** results highlight a distinct divergence in stress and pore pressure fields when comparing wellbores with negative skin zones to those with positive skin zones or no skin at all.

关键词： Poroelastic Graded permeability Analytical solution Wellbore Skin zone

镉胁迫下钝化剂对菠菜生理特征及镉累积的影响

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农业环境科学学报 2023年第5期42卷 1004-1010页

作者：王丽蔡景行罗沐欣键吴道明范洪黎秦松范成五贵州省农业科学院土壤肥料研究所贵阳550006 贵阳市乡村振兴服务中心贵阳550081 中国农业科学院农业资源与农业区划研究所/耕地保护国家工程研究中心/农业农村部植物营养与肥料重点实验室北京100081

为了探究不同钝化剂在镉(Cd)胁迫下对蔬菜生理特征及Cd累积的影响,以菠菜为研究对象,设置不施钝化剂(CK)、单施纳米羟基磷灰石(nHAP)、单施巯基生物炭(TMB)、配施纳米羟基磷灰石+巯基生物炭(HPTB)4个处理进行盆栽试验。通过测定分析土... 详细信息

为了探究不同钝化剂在镉(Cd)胁迫下对蔬菜生理特征及Cd累积的影响,以菠菜为研究对象,设置不施钝化剂(CK)、单施纳米羟基磷灰石(nHAP)、单施巯基生物炭(TMB)、配施纳米羟基磷灰石+巯基生物炭(HPTB)4个处理进行盆栽试验。通过测定分析土壤pH、有效态Cd含量及菠菜抗氧化酶活性,阐明施用不同钝化剂对Cd胁迫下菠菜生长及Cd累积的影响。结果表明:施加钝化剂能有效提高菠菜生物量,降低菠菜Cd含量。与CK相比,nHAP、TMB、HPTB处理下地上部和地下部生物量分别增加了90.27%、7.28%、143.75%和72.50%、4.81%、91.71%,Cd含量分别降低了78.19%、6.94%、65.49%和65.98%、39.34%、52.31%;不同钝化剂均能提高土壤pH,降低土壤有效态Cd含量。nHAP、TMB、HPTB处理下土壤pH较CK分别提高了1.36、0.08个和0.76个单位,有效态Cd含量分别降低了83.22%、22.57%和73.70%。nHAP处理对菠菜的降Cd效果最好;施用nHAP能够有效增加抗氧化酶活性,降低丙二醛含量,缓解脂膜过氧化伤害。综上,nHAP可作为缓解Cd污染对菠菜产生生理影响的钝化剂。

关键词：镉钝化剂菠菜抗氧化酶