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Electrocatalytic Oxidation of Calcium Folinate on Carboxyl Graphene Modified CuxO/Cu Electrode

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Chinese Journal of Chemical Physics 2016年第6期29卷 729-734,I0002页

作者： li-wen Wang Shou-guo Wu Tian-yang Shi Wei Wei pan pan Departmentol:Chemistry UniversityofScienceandTechnologyofChinaHefei230026China

Carboxyl graphene modified CuxO/Cu electrode was fabricated. The bare copper electrode was firstly anodic polarized in 1.0 mol/L NaOH solution in order to get CuxO nanoparticles, then the carboxyl graphene （CG） was electrodeposited on the CuxO/Cu electrode by cyclic potential sweeping. The electrocatalytic oxidation behaviors of calcium folinate （CF） at the graphene modified CuxO/Cu electrode were investigated by cyclic voltammetry. A positive scan polarization reverse catalytic voltammetry was used to obtain the pure catalytic oxidation current. The graphene modified CuxO/Cu electrode was served as the electrochemical sensor of CF, a highly sensitivity of 22.0μA.（μmol/μL）^-1cm^-2 was achieved, and the current response was linear with increasing CF concentration in the range of 2.0×10^-7 mol/L to 2.0×10^-5 mol/L, which crossed three orders of magnitude, and the detection limit was found 7.6×10^-5 mol/L （S/N=3）. In addition, the proposed sensor was successfully applied in determination of CF in drug sample.

关键词： Calcium folinate Carboxyl graphene CuxO/Cu electrode Chemically modi-fied electrode Positive scan polarization reverse catalytic voltammetry

Deep Learning Based Signal Detector for OFDM Systems

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China Communications 2023年第12期20卷 66-77页

作者： Guangliang pan Wei Wang Minglei li Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space Ministry of Industry and Information TechnologyCollege of Electronic and Information EngineeringNanjing University of Aeronautics and AstronauticsNanjing 211106China College of Control Science and Engineering China University of Petroleum(East China)Qingdao 266580China

In this paper,we propose a novel deep learning(DL)-based receiver design for orthogonal frequency division multiplexing(OFDM)*** entire process of channel estimation,equalization,and signal detection is replaced by a neural network(NN),and hence,the detector is called a NN detector(N^(2)D).First,an OFDM signal model is *** analyze both temporal and spectral characteristics of OFDM signals,which are the motivation for ***,the generated data based on the simulation of channel statistics is used for offline training of bi-directional long short-term memory(Bi-LSTM)***,a discriminator(F)is added to the input of Bi-LSTM NN to look for subcarrier transmission data with optimal channel gain(OCG),which can greatly improve the performance of the ***,the trained N^(2)D is used for online recovery of OFDM *** performance of the proposed N^(2)D is analyzed theoretically in terms of bit error rate(BER)by Monte Carlo simulation under different parameter *** simulation results demonstrate that the BER of N^(2)D is obviously lower than other algorithms,especially at high signal-to-noise ratios(SNRs).Meanwhile,the proposed N^(2)D is robust to the fluctuation of parameter values.

关键词： channel estimation deep learning OFDM optimal channel gain signal detection

Effects of nitrogen addition on the soil detachment in the typical grasslands of the Loess Plateau

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Journal of Mountain Science 2022年第12期19卷 3503-3516页

作者： li pan-pan WANG Bing YANG Yan-fen liU Guo-bin State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China

Nitrogen deposition will alleviate the nitrogen limitation in terrestrial ecosystems and greatly affect vegetation growth,thereby soil *** is important to clarify the effects of nitrogen addition to the plant roots and soil properties on the soil erosion process.A nitrogen addition experiment was conducted in the grassland dominated by Bothriochloa ischaemum(linn.)Keng(BI),which has received 0,2.5,5,and 10 g N m^(-2) yr^(-1)(N_(0),N_(2.5),N_(5)and N_(10),respectively)for three consecutive ***,a total of 150 undisturbed soil samples were collected(including bare soil control)and subjected to flowing water to test their soil detachment capacities under six shear stress levels(10.2 Pa to 29.9 Pa).Three-year nitrogen addition increased the soil bulk density,soil cohesion and nitrate nitrogen while decreasing the saturated hydraulic conductivity,soil water-stable aggregates,soil organic carbon,total nitrogen and ammonium *** root mass density and root diameter decreased with nitrogen *** the root length,surface area and volume density of the N_(0) and N_(5) treatments were larger than those of the other treatments,while the plant roots were significantly inhibited by N_(10).Additionally,the soil detachment capacity(D_(c))and rill erodibility(K_(r))of the N_(0) and N_(5) treatments were significantly less than those of the N_(2.5) and N_(10)treatments,of which the Dc(0.020 kg m^(-2) s^(-1))of the N_(0) treatment was 69.0%,24.3%and 66.8%less than that of the N_(2.5),N_(5) and N_(10) treatments,*** Kr of the N_(0) treatment was 0.0012 s m^(-1),which was 72.1%,25.0%and 70.0%less than that of the *** study implies that an increase in nitrogen addition likely exacerbates soil erosion in the early(approximately 2.5 g N m^(-2) yr^(-1))and late phases(more than 10 g N m^(-2) yr^(-1)).However,when the nitrogen addition rate is approximately 5 g m^(-2) yr^(-1),soil erosion may be inhibited because of the responses of the plant ro

关键词： Nitrogen deposition Root traits Soil properties Soil detachment Grassland Loess Plateau

Rapid evaluation of arsenic contamination in paddy soils using field portable X-ray fluorescence spectrometry

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Journal of Environmental Sciences 2018年第2期30卷 345-351页

作者： Jian-Hong liang pan-pan liu Zheng Chen Guo-Xin Sun Hong li Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification Institute of Karst Geology Chinese Academy of Geological Sciences Guilin 541004 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Department of Environmental Science Xi' an Jiaotong-Liverpool University Suzhou 215123 China College of Urban Construction and Environmental Engineering Chongqing University Chongqing 400045 China

Arsenic（As） in paddy fields is deteriorating food security and human health through rice ingestion. Rice is the dominant food source of arsenic exposure to half of the world’s population. Therefore, an in situ effective method for As risk evaluation in paddy soil is strongly needed to avoid As exposure through rice ingestion. Herein, we developed a rapid analytical methodology for determination of As in plant tissues using field portable X-ray fluorescence spectrometry（FP-XRF）. This method was applied to rice roots in order to evaluate the As contamination in paddy soils. The results showed that rice roots with iron plaques were superior to rhizosphere soils for generating FP-XRF signals, especially for field sites with As concentrations lower than the soil detection limit of FP-XRF（30.0 mg/kg）.Moreover, the strong linear relationships of As concentrations between the rice roots and corresponding leaves and grains proved that the rice root, rather than the soil, is a better predictor of As concentrations in rice grains. The research provides an efficient As monitoring method for As contaminated paddy fields by using wetland plant roots with iron plaques and XRF-based analytical techniques.

关键词： XRF Arsenic Risk evaluation Rice roots Rhizosphere soils Iron plaque

Mg^(2+) improves biomass production from soybean wastewater using purple non-sulfur bacteria

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Journal of Environmental Sciences 2015年第2期27卷 43-46页

作者： pan Wu Guangming Zhang Jianzheng li State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology School of Environment & Resource Renmin University of China

Soybean wastewater was used to generate biomass resource by use of purple non-sulfur bacteria（PNSB）. This study investigated the enhancement of PNSB cell accumulation in wastewater by Mg2＋under the light-anaerobic condition. Results showed that with the optimal Mg2＋dosage of 10 mg/L, biomass production was improved by 70% to 3630 mg/L,and biomass yield also was improved by 60%. Chemical Oxygen Demand（COD） removal reached above 86% and hydraulic retention time was shortened from 96 to 72 hr. The mechanism analysis indicated that Mg2＋could promote the content of bacteriochlorophyll in photosynthesis because Mg2＋is the bacteriochlorophyll active center, and thus improved adenosine triphosphate（ATP） production. An increase of ATP production enhanced the conversion of organic matter in wastewater into PNSB cell materials（biomass yield） and COD removal, leading to more biomass production. With 10 mg/L Mg2＋, bacteriochlorophyll content and ATP production were improved by 60% and 33% respectively.

关键词： Purple non-sulfur bacteria Mg2+ Biomass resource Soybean wastewater Photosynthesis

Channel Estimation for Reconfigurable Intelligent Surface Aided Multiuser Millimeter-Wave/THz Systems

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China Communications 2024年第3期21卷 91-103页

作者： Chu Hongyun pan Xue li Baijiang School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

It is assumed that reconfigurable intelligent surface(RIS)is a key technology to enable the potential of mmWave *** passivity of the RIS makes channel estimation difficult because the channel can only be measured at the transceiver and not at the *** this paper,we propose a novel separate channel estimator via exploiting the cascaded sparsity in the continuously valued angular domain of the cascaded channel for the RIS-enabled millimeter-wave/Tera-Hz systems,i.e.,the two-stage estimation method where the cascaded channel is separated into the base station(BS)-RIS and the RIS-user(UE)***,we first reveal the cascaded sparsity,i.e.,the sparsity exists in the hybrid angular domains of BS-RIS and the RIS-UEs separated channels,to construct the specific sparsity structure for RIS enabled multi-user ***,we formulate the channel estimation problem using atomic norm minimization(ANM)to enhance the proposed sparsity structure in the continuous angular domains,where a low-complexity channel estimator via Alternating Direction Method of Multipliers(ADMM)is *** findings demonstrate that the proposed channel estimator outperforms the current state-of-the-arts in terms of performance.

关键词： atomic norm minimization cascaded channel estimation convex optimization mmWave/THz reconfigurable intelligent surface(RIS) sparsity

Prospective study of the effect of ERAS on postoperative recovery and complications in patients with gastric cancer

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Cancer Biology & Medicine 2022年第8期19卷 1274-1281页

作者： Ye Tian Qiang li Yuan pan Tianjin Medical University Cancer Institute and Hospital National Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerTianjin 300060China

Objective:To study the efficacy of the enhanced recovery after surgery(ERAS)program on postoperative recovery and complications in patients with gastric ***:Eighty patients in the perioperative period with radical gastrectomy were enrolled and randomly divided into 2 groups,the ERAS group and the non-ERAS *** differences between the 2 groups in terms of postoperative recoveries and complications rate were *** to the body mass index(BMI)level,the ERAS group was divided into 2 subgroups,namely group A(BMIlications of each group were then ***:The postoperative length of stay and visual analogue scale pain score were less in the ERAS group than the non-ERAS group(P<0.05).Time to first postoperative exhaustion,first postoperative defecation,returning leukocyte count to normal,and stopping intravenous nutrition were significantly shorter in the ERAS group(n=40),compared to the non-ERAS group(n=40,all P<0.05).The incidence of postoperative lower extremity intramuscular venous thrombosis was significantly higher in group D than in group B(χ2=4.800,P=0.028).In addition,the incidence of lower extremity intermuscular venous thrombosis and lung infection in group D was higher than those in other ***:The perioperative ERAS program was associated with faster recovery in patients undergoing radical *** patients with higher BMI(BMI≥28 kg/m2),the use of the perioperative ERAS program was more advantageous.

关键词： Enhanced recovery after surgery body mass index gastric cancer laparoscope complication

Sorption of pyrene on two paddy soils and their particle-size fractions

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Journal of Environmental Sciences 2005年第6期17卷 962-965页

作者： li Jiu-hai pan Gen-xing Institute of Resources Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 China

In the present study, the sorption of pyrene on two kinds of bulk paddy soils, Gleyic Stagnic Anthrosols, and Ferric accumulic Stagnic Anthrosols as well as their particle-size fractions was investigated. The sorption isotherms fitted well with Freundlich equation. For both soils, the clay fraction（〈 2μm） and coarse sand fraction（2000-250μm） had higher sorption capacity than fine sand fraction（250-20 μm） and silt fraction（20-2 μm）. The IogKoc values obtained of each soil and its particle-size fractions were similar, proving that SOM content was a key factor affecting pyrene sorption. The Kd values showed a significant correlation with contents of dithionite-extractable Fe in both paddy soils and a good relationship with CEC in Gleyic Stagnic Anthrosols, indicating possible effects of surface properties of particle-size fractions on the sorption of pyrene.

关键词： paddy soil particle-size fraction PAHs sorption

The Law of Logarithm for Arrays of Random Variables under Sub-linear Expectations

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 670-688页

作者： Jia-pan XU li-xin ZHANG School of Mathematical Sciences Zhejiang UniversityHangzhou310027China

Under the framework of sub-linear expectation initiated by Peng,motivated by the concept of extended negative dependence,we establish a law of logarithm for arrays of row-wise extended negatively dependent random variables under weak ***,the law of logarithm for independent and identically distributed arrays is derived more precisely and the sufficient and necessary conditions for the law of logarithm are obtained.

关键词： sub-linear expectation capacity exponential inequality extended negative dependence the law of logarithm