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Agricultural non-point nitrogen pollution control function of dierent vegetation types in riparian wetlands: A case study in the Yellow River wetland in China

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Journal of Environmental Sciences 2009年第7期21卷 933-939页

作者： ZHAO Tongqian XU Huashan he yuxiao TAI Chao MENG Hongqi ZENG Fanfu XING Menglin Institute of Resources and Environment Henan Polytechnic University Jiaozuo 454003 China henan Province Environmental Monitoring Center Zhengzhou 450004 China

Riparian wetland is the major transition zone of matter, energy and information transfer between aquatic and terrestrial ecosystems and has important functions of water purification and non-point pollution control. Using the field experiment method and an isotope tracing technique, the agricultural non-point nitrogen pollution control function of different vegetation types in riparian wetland was studied in the Kouma Section of the Yellow River. The results showed that the retention of agricultural non-point nitrogen pollution by riparian wetland soil occurs mainly in top 0-10 cm layer. The amount of nitrogen retained by surface soils associated with three types of vegetation are 0.045 mg/g for Phragmites communis Trin Linn, 0.036 mg/g for Scirpus triqueter Linn, and 0.032 mg/g for Typha angustifolia Linn, which account for 59.21%, 56.25%, and 56.14% of the total nitrogen interception, respectively. Exogenous nitrogen in 0-10 cm soil layer changes more quickly than in other layers. One month after adding KISNO3 to the tested vegetation, nitrogen content was 77.78% for P communis Trin, 68.75% for T. angustifolia, and 8.33% for S. triqueter in the surface soil. After three months, nitrogen content was 93.33% for P. communis Trin, 72.22% for S. triqueter, and 37.50% for T. Angustifolia. There are large differences among vegetation communities respecting to purification of agricultural non-point nitrogen pollution. The nitrogen uptake amount decreases in the sequence： new shoots ofP. communis Trin （9.731 nag/g）〉 old P. communis Trin （4.939 mg/g）〉 S. triqueter （0.620 mg/g）〉 T. angustifolia （0.186 mg/g）. Observations indicated that the presence of riparian wetlands as buffers on and adjacent to stream banks could be recommended to control agricultural non-point pollution.

关键词： riparian wetland vegetation community agricultural non-point source nitrogen pollution

Molecular dynamics analysis on bending mechanical behavior of alumina nanowires at different loading rates

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Transactions of Nonferrous Metals Society of China 2022年第11期32卷 3687-3698页

作者： yuxiao James he Bin MA School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China School of Architecture and Traffic Engineering Guilin University of Electronic TechnologyGuilin 541004China

The molecular dynamics(MD)model ofα-Al_(2)O_(3) nanowires in bending is established by using LAMMPS to calculate the atomic stress and strain at different loading rates in order to study the effect of loading rate on the bending mechanical behaviors of theα-Al_(2)O_(3) *** results show that the maximum surface stress−rotation angle curves ofα-Al_(2)O_(3) nanowires at different loading rates are all divided into three stages of elastic deformation,plastic deformation and failure,where the elastic limit point can be determined by the curve symmetry during loading and unloading *** loading rate has great influence on the plastic deformation but little on the elastic modulus ofα-Al_(2)O_(3) *** the loading rate is increased,the plastic deformation stage is shortened and the material is easier to fail in brittle ***,the elastic limit and the strength limit(determined by the direct and indirect MD simulation methods)are closer to each *** MD simulation result ofα-Al_(2)O_(3) nanowires is verified to be valid by the good agreement with the improved loop test *** direct MD method becomes an effective way to determine the elastic limit and the strength limit of nanoscale whiskers failed in brittle or ductile fracture at arbitrary loading rate.

关键词： alumina nanowires bending behavior loading rate elastic limit strength limit molecular dynamics

Plackett-Burman设计结合Box-Behnken响应面法筛选草乌甲素纳米乳凝胶贴膏的处方

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西北药学杂志 2024年第1期39卷 92-98页

作者：何雨晓李丽云孙文强丁江生周云龙云南中医药大学昆明650500 云南省药物研究所昆明650111 云南省中药和民族药新药创制企业重点实验室昆明650111

目的优化草乌甲素纳米乳凝胶贴膏基质的处方。方法在Plackett-Burman设计、最陡爬坡实验的基础上,以甘油、酒石酸、纯化水用量作为变量,以初黏力、持黏力、感官评价的综合评分为评价指标,用Box-Behnken响应面法优化草乌甲素纳米乳凝胶... 详细信息

目的优化草乌甲素纳米乳凝胶贴膏基质的处方。方法在Plackett-Burman设计、最陡爬坡实验的基础上,以甘油、酒石酸、纯化水用量作为变量,以初黏力、持黏力、感官评价的综合评分为评价指标,用Box-Behnken响应面法优化草乌甲素纳米乳凝胶贴膏基质的处方。结果最优处方为甘油用量40.877 g,酒石酸用量0.294 g,纯化水用量42.491 g,综合评分为94.937分。结论建立的方法稳定、可靠、预测性能优良,此方法可用于优化草乌甲素纳米乳凝胶贴膏基质的处方。

关键词：草乌甲素纳米乳凝胶贴膏 Plackett-Burman设计

基于多性状模型内蒙古绒山羊早期生长性状基因组预测准确性研究

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遗传 2024年第5期46卷 421-430页

作者：高林豫许琦何钰霄习海娇刘一帆张涛李金泉张燕军王瑞军吕琦梅步俊苏蕊王志英内蒙古农业大学动物科学学院呼和浩特010018 农业农村部肉羊遗传育种重点实验室呼和浩特010018 内蒙古自治区羊遗传育种与繁殖重点实验室呼和浩特010018 河套学院农学系巴彦淖尔015000

内蒙古绒山羊是经过长期自然选择和人工选育后形成的优良家畜品种,是目前世界一流的绒肉兼用山羊。多性状动物模型被认为可以显著提高畜禽遗传评估的准确性,实现性状间的间接选择。本文基于内蒙古绒山羊个体的系谱、基因型、环境以及早... 详细信息

内蒙古绒山羊是经过长期自然选择和人工选育后形成的优良家畜品种,是目前世界一流的绒肉兼用山羊。多性状动物模型被认为可以显著提高畜禽遗传评估的准确性,实现性状间的间接选择。本文基于内蒙古绒山羊个体的系谱、基因型、环境以及早期生长性状的表型记录,建立多性状动物模型,利用ABLUP、GBLUP、ssGBLUP三种方法进行早期生长性状(初生重、断乳重、断乳前平均日增重、周岁重)遗传参数及基因组育种值的估计,进一步利用五倍交叉验证方法评价基因组育种值估计准确性和可靠性。结果显示,3种方法估计的初生重遗传力为0.13~0.15,断乳重遗传力为0.13~0.20,日增重遗传力为0.11~0.14,周岁重遗传力为0.09~0.14,均属于中等偏低遗传力;断乳重和日增重、日增重和周岁重之间存在强的正遗传相关,相关系数分别为0.77~0.79和0.56~0.67,表型相关发现同样的规律;ABLUP、GBLUP和ssGBLUP法估计的初生重育种值准确性分别为0.5047、0.6694、0.7156,断乳重分别为0.6207、0.6456、0.7254;日增重分别为0.6110、0.6855、0.7357,周岁重分别为0.6209、0.7155、0.7756。综上所述,内蒙古绒山羊早期生长性状属于中等偏低遗传力,对其进行遗传选育改良速度相对较慢;通过对断乳重的选择可以实现其他生长性状的遗传改良;ssGBLUP方法估计内蒙古绒山羊早期生长性状基因组育种值的准确性和可靠性均最高,且显著高于ABLUP法,说明该方法是内蒙古绒山羊早期性状基因组选育的最佳方法。

关键词：内蒙古绒山羊早期生长性状多性状动物模型基因组育种值估计准确性

Reconfigurable optical neural networks with Plug-and-Play metasurfaces

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Opto-Electronic Advances 2024年第7期7卷 1-3页

作者： Yongmin Liu yuxiao Li Department of Mechanical and Industrial Engineering Northeastern UniversityBostonMassachusetts 02115USA Department of Electrical and Computer Engineering Northeastern UniversityBostonMassachusetts 02115USA

In a very recent study,*** Huang and co-workers proposed and demonstrated reconfigurable optical neural networks based on cascaded *** fixing one metasurface and switching the other pluggable metasurfaces,the neural networks,which operate at near-infrared wavelengths,can perform distinct recognition tasks for handwritten digits and fashion *** innovative device opens up an avenue for all-optical,high-speed,low-power,and multifunctional artificial intelligence systems.

关键词： surfaces networks neural

ASYMPTOTIC BEHAVIOR NEAR The BOUNDARY OF A LARGE SOLUTION TO SEMILINEAR POISSON EQUATION WITH DOUBLE-POWER NONLINEARITY

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Acta Mathematica Scientia 2024年第6期44卷 2083-2098页

作者： Kazuhiro TAKIMOTO yuxiao ZHANG Department of Mathematics Graduate School of Advanced Science and TechnologyHiroshima University

We deal with a large solution to the semilinear Poisson equation with doublepower nonlinearity Δu=up+αuqin a bounded smooth domain D ■ R~n,where p> 1,-1 he asymptotic behavior of a solut... 详细信息

关键词： asymptotic behavior double-power nonlinearity large solution semilinear Poisson equation

Ash removal from inferior coal via ammonium fluoride roasting and simultaneous yield of white carbon black

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International Journal of Mining Science and Technology 2024年第2期34卷 261-279页

作者： Xuqin Duan Shuaiyu Lu yuxiao Fu Jiazhe Zhang Tong Liu Jian Ma School of Civil and Resource Engineering University of Science&Technology BeijingBeijing 100083China State Key Laboratory for Efficient Mining of Metal Mines University of Science&Technology BeijingBeijing 100083China China Coal Processing and Utilizaiton Association Beijing 100013China

The quality upgrading and deashing of inferior coal by chemical method still faces great *** dangers of strong acid,strong alkali,waste water and exhaust gas as well as high cost limit its industrial *** paper systematically investigates the ash reduction and desilicification of two typical inferior coal utilizing ammonium fluoride roasting *** the optimal conditions,for fat coal and gas coal,the deashing rates are 69.02%and 54.13%,and the desilicification rates are 92.64%and 90.27%,*** molar dosage of ammonium fluoride remains consistent for both coals;however,the gas coal,characterized by a lower ash and silica content(less than half that of the fat coal),achieves optimum deashing effect at a reduced time and *** majority of silicon in coal transforms into gaseous ammonium fluorosilicate,subsequently preparing nanoscale amorphous silica with a purity of 99.90%through ammonia *** of the fluorine in deashed coal are assigned in inorganic minerals,suggesting the possibility of further fluorine and ash removal via *** research provides a green and facile route to deash inferior coal and produce nano-scale white carbon black simultaneously.

关键词： Inferior coal Deashing treatment Silicon recycling Ammonium fluoride roasting White carbon black

A Study of Epileptogenic Foci Localization Algorithm Based on Automatic Detection of Comprehensive Feature HFOs and RF-LR

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Chinese Journal of Electronics 2024年

作者： yuxiao DU Gaoming LI School of Automation Guangdong University of Technology

Studies have shown that fast ripples of 250–500 Hz in epileptic electroencephalography(EEG) signals are more pathological and closer to the epileptogenic focus itself compared to ripples of 80–250 Hz. However, artifacts of fast ripples and high-frequency oscillations(HFOs) are easily confused and difficult to discriminate, and manual visual screening is both time-consuming and unable to avoid subjectivity. To this end, this paper presents a method for localizing epileptogenic foci based on the automatic detection of integrated feature HFOs and random forest-logistic regression(RF-LR). In this paper, we first extract multivariate features from the preprocessed epileptic EEG signals, and use the random forest algorithm to filter out three features with high importance, based on which,suspicious leads containing HFOs are identified. Then, wavelet time-frequency maps were used for the primary screening of suspected leads to improve the signal calibration efficiency and further localize HFOs in time and frequency. Finally, a logistic regression model was used to automatically classify and identify ripples and fast ripples in HFOs. The results show that the sensitivity, specificity, and accuracy of the model for detecting ripple are 89.37%, 88.26%, and 90.1%, respectively; the sensitivity, specificity, and accuracy for detecting fast ripple are 94.31%, 94.83%,and 93.46%, respectively. Compared with single features, the multivariate features in this paper more comprehensively characterize the complex epileptic EEG signals and provide more accurate information for the localization of epileptogenic foci. The automatic detection algorithm of HFOs proposed in this paper can analyze a large amount of data in a short time and has a good detection performance, which can help clinicians accurately determine the region of epileptogenic foci.

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Etching Mechanism of Ti_(3)C_(2)Cl_(2) MXene Phases by CuCl_(2)-Lewis Molten Salt Method

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 863-868页

作者：严明 ZHU Yu HUANG Jiangtao CheN Haoyu DENG yuxiao CheN Yanlin 王娟 Jan-Michael Albina Hubei Provincial Key Laboratory of Green Materials for Light Industry Hubei University of TechnologyWuhan 430068China New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base Hubei University of TechnologyWuhan 430068China Hubei Longzhong Laboratory Xiangyang 441000China

We described a method for obtaining fluorine-free Ti_(3)C_(2)Cl_(2)MXene phases by melting copper in CuCl_(2)instead of aluminum in Ti_(3)AlC_(2).XRD results show that when molten salt CuCl_(2)etches Ti_(3)AlC_(2),it forms an intermediate product Ti_(3)CuC_(2),and then reacts with Ti_(3)CuC_(2)to obtain Ti_(3)C_(2)Cl_(2).The reaction of Ti_(3)AlC_(2)and CuCl_(2)at a temperature of 800℃for 2 h to obtain Ti_(3)C_(2)Cl_(2)with an optimal lamellar structure is shown in SEM *** pseudopotential plane-wave(PP-PW)method is used to calculate on the electronic *** etching mechanism is investigated by the total energies of each *** chemical reaction of Ti_(3)AlC_(2)and CuCl_(2)will first become Ti_(3)CuC_(2)and Cu,and then become Ti_(3)C_(2)Cl_(2)during the Lewis acid etching process,which are consistent with the experimental results.

关键词： molten salt method CuCl_(2) MXene first-principles calculations etching mechanism