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Effects of cadium, zinc and lead on soil enzyme activities

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Journal of Environmental Sciences 2006年第6期18卷 1135-1141页

作者： YANG Zhi-xin LIU Shu-qing zheng da-wei FENG Sheng-dong College of Resource and Environment China Agricultural University Beijing 100094 China College of Resource and Environment Agricultural University of Hebei Baoding 071001 China

Heavy metal （HM） is a major hazard to the soil-plant system. This study investigated the combined effects of cadium （Cd）, zinc （Zn） and lead （Pb） on activities of four enzymes in soil, including calatase, urease, invertase and alkalin phosphatase. HM content in tops of canola and four enzymes activities in soil were analyzed at two months after the metal additions to the soil. Pb was not significantly inhibitory than the other heavy metals for the four enzyme activities and was shown to have a protective role on calatase activity in the combined presence of Cd, Zn and Pb; whereas Cd significantly inhibited the four enzyme activities, and Zn only inhibited urease and calatase activities. The inhibiting effect of Cd and Zn on urease and calatase activities can be intensified significantly by the additions of Zn and Cd. There was a negative synergistic inhibitory effect of Cd and Zn on the two enzymes in the presence of Cd, Zn and Pb. The urease activity was inhibited more by the HM combinations than by the metals alone and reduced approximately 20%--40% of urease activity. The intertase and alkaline phosphatase activities significantly decreased only with the increase of Cd concentration in the soil. It was shown that urease was much more sensitive to HM than the other enzymes. There was a obvious negative correlation between the ionic impulsion of HM in soil, the ionic impulsion of HM in canola plants tops and urease activity. It is concluded that the soil urease activity may be a sensitive tool for assessing additive toxic combination effect on soil biochemical parameters.

关键词： multiple heavy metal pollution canola plants soil enzyme ionic impulsion

基于CIPP模式的职业院校产教融合质量评价指标体系研究

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高等职业教育探索 2024年第2期23卷 64-71页

作者：孙健王琦琪郑大伟周向峰江苏理工学院江苏常州213001 苏州大学江苏苏州215031 江苏省职教学会江苏南京210024

职业院校产教融合质量评价是以职业院校产教融合行为作为对象,依据一定的评价原则与标准,以满足利益相关方要求为目的开展的系统性价值判断。CIPP评价作为一种全过程评价,与职业院校产教融合质量评价思路高度吻合。有必要以CIPP模式作... 详细信息

职业院校产教融合质量评价是以职业院校产教融合行为作为对象,依据一定的评价原则与标准,以满足利益相关方要求为目的开展的系统性价值判断。CIPP评价作为一种全过程评价,与职业院校产教融合质量评价思路高度吻合。有必要以CIPP模式作为框架,借助SPSS和AMOS等分析工具,构建职业院校产教融合质量评价指标,同时,以层次分析法(AHP)确立评价指标权重,最终形成基于CIPP模式的职业院校产教融合质量评价指标体系。

关键词：职业院校 CIPP模式产教融合质量 AHP 评价指标体系

On-surface synthesis and characterization of polyynic carbon chains

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National Science Review 2024年第3期11卷 192-199页

作者： Wenze Gao wei zheng Luye Sun Faming Kang zheng Zhou wei Xu Interdisciplinary Materials Research Center School of Materials Science and Engineering Tongji University

Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au（111） surface;the longest one observed consists of ～60 alkyne units（120 carbon atoms）. The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule(C14Cl10) on a bilayer NaCl/Au（111） surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy,in a good agreement with the theoretical HOMO–LUMO gap（5.48 eV）.

关键词： polyyne scanning probe microscopy carbon allotrope on-surface synthesis organometallic polyyne

Accurately tracking hypersonic gliding vehicles via an LEO mega-constellation in relay tracking mode

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Journal of Systems Engineering and Electronics 2024年第1期35卷 211-221页

作者： LI Zhao WANG Yidi zheng wei College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

In order to effectively defend against the threats of the hypersonic gliding vehicles(HGVs),HGVs should be tracked as early as possible,which is beyond the capability of the ground-based *** benefited by the developing megaconstellations in low-Earth orbit,this paper proposes a relay tracking mode to track HGVs to overcome the above *** whole tracking mission is composed of several tracking intervals with the same *** each tracking interval,several appropriate satellites are dispatched to track the *** that are planned to take part in the tracking mission are selected by a new derived observability *** tracking performances of the proposed tracking mode and the other two traditional tracking modes,including the stare and track-rate modes,are compared by *** results show that the relay tracking mode can track the whole trajectory of a HGV,while the stare mode can only provide a very short tracking ***,the relay tracking mode achieve higher tracking accuracy with fewer attitude controls than the track-rate mode.

关键词： target tracking mega-constellation hypersonic gliding vehicle(HGV) sensor selection observability analysis

Improving the spaceborne GNSS-R altimetric precision based on the novel multilayer feedforward neural network weighted joint prediction model

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Defence Technology（防务技术） 2024年第2期32卷 271-284页

作者： Yiwen Zhang wei zheng Zongqiang Liu Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China China Academy of Aerospace Science and Innovation Beijing 100176China State Key Laboratory of Space-Ground Integrated Information Technology Beijing Institute of Satellite Information EngineeringBeijing 100194China

Global navigation satellite system-reflection(GNSS-R)sea surface altimetry based on satellite constellation platforms has become a new research direction and inevitable trend,which can meet the altimetric precision at the global scale required for underwater *** present,there are still research gaps for GNSS-R altimetry under this mode,and its altimetric capability cannot be specifically ***,GNSS-R satellite constellations that meet the global altimetry needs to be ***,the matching precision prediction model needs to be established to quantitatively predict the GNSS-R constellation altimetric ***,the GNSS-R constellations altimetric precision under different configuration parameters is calculated,and the mechanism of the influence of orbital altitude,orbital inclination,number of satellites and simulation period on the precision is analyzed,and a new multilayer feedforward neural network weighted joint prediction model is ***,the fit of the prediction model is verified and the performance capability of the model is tested by calculating the R2 value of the model as 0.9972 and the root mean square error(RMSE)as 0.0022,which indicates that the prediction capability of the model is ***,using the novel multilayer feedforward neural network weighted joint prediction model,and considering the research results and realistic costs,it is proposed that when the constellation is set to an orbital altitude of 500 km,orbital inclination of 75and the number of satellites is 6,the altimetry precision can reach 0.0732 m within one year simulation period,which can meet the requirements of underwater navigation precision,and thus can provide a reference basis for subsequent research on spaceborne GNSS-R sea surface altimetry.

关键词： GNSS-R satellite constellations Sea surface altimetric precision Underwater navigation Multilayer feedforward neural network

Long-term outcome of correction of tetralogy of Fallot in 56 adult patients

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Chinese Medical Journal 2013年第19期126卷 3675-3679页

作者： zheng da-wei SHAO Guo-feng FENG Qiang NI Yi-ming Department of Cardiothoracic Surgery the First Affiliated HospitalZhejiang University School of Medicine Hangzhou Zhejiang310003 China Department of Cardiothoracic Surgery Ningbo Medical CentreLihuili Hospital Ningbo Zhejiang 315041 China

Background Although most patients with tetralogy of Fallot undergo radical repair during infancy and childhood,patients that remain undiagnosed and untreated until adulthood can still be *** study aimed to evaluate longterm outcomes of adult patients with tetralogy of Fallot who were treated surgically,and to determine the predictors of postoperative pulmonary *** Fifty-six adult patients underwent complete surgical ***-three patients （76.8%） required a transannular ***,diastolic,and mean pressure in the main pulmonary artery were measured after *** The early mortality rate was 3.6%.The 16-year survival rate was （84.4±11.5）%.Late echocardiography revealed 41 patients with transannular patch who had pulmonary regurgitation,consisting of mild pulmonary regurgitation in 28 patients,moderate in eight,and severe regurgitation in five *** addition,there was right ventricular outflow tract stenosis in nine patients,moderate/severe tricuspid valve regurgitation in seven,and residual ventricular septal defect in *** regression analysis demonstrated that the mean pulmonary pressure measured just after repair predicted late pulmonary *** The long-term survival of surgically treated adult patients with tetralogy of Fallot is *** mean pressure 〉20 mmHg in the main pulmonary artery measured right after surgical repair may be a feasible reference to time the reconstruction of the pulmonary valve.

关键词： tetralogy of Fallot pulmonary regurgitation pulmonary artery pressure congenital heart disease

Liquid lens based holographic camera for real 3D scene hologram acquisition using end-to-end physical model-driven network

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Light(Science & Applications) 2024年第3期13卷 488-497页

作者： Di Wang Zhao-Song Li Yi zheng You-Ran Zhao Chao Liu Jin-Bo Xu Yi-wei zheng Qian Huang Chen-Liang Chang da-wei Zhang Song-Lin Zhuang Qiong-Hua Wang School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China

With the development of artificial intelligence,neural network provides unique opportunities for holography,such as high fidelity and dynamic *** to obtain real 3D scene and generate high fidelity hologram in real time is an urgent ***,we propose a liquid lens based holographic camera for real 3D scene hologram acquisition using an end-to-end physical model-driven network(EEPMD-Net).As the core component of the liquid camera,the first 10 mm large aperture electrowetting-based liquid lens is proposed by using specially fabricated *** design of the liquid camera ensures that the multi-layers of the real 3D scene can be obtained quickly and with great imaging *** EEPMD-Net takes the information of real 3D scene as the input,and uses two new structures of encoder and decoder networks to realize low-noise phase *** comparing the intensity information between the reconstructed image after depth fusion and the target scene,the composite loss function is constructed for phase optimization,and the high-fidelity training of hologram with true depth of the 3D scene is realized for the first *** holographic camera achieves the high-fidelity and fast generation of the hologram of the real 3D scene,and the reconstructed experiment proves that the holographic image has the advantage of low *** proposed holographic camera is unique and can be used in 3D display,measurement,encryption and other fields.

关键词： calculation solution holographic

Cidan Capsule in Combination with Adjuvant Transarterial Chemoembolization Reduces Recurrence Rate after Curative Resection of Hepatocellular Carcinoma:A Multicenter,Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2023年第1期29卷 3-9页

作者： zheng Dong-hai YANG Jia-mei WU Jian-xiong CHENG Shu-qun ZHANG Shao-geng WU Dong LI Aijun FU Xiao-hui LI Xun QI Fu-chen DUAN wei-hong CHEN Jun-hui YANG Zhi-ying LIANG Lu ZENG Jin-xiong zheng wei-da WU Meng-chao Department of Oncology Beijing Weida Traditional Chinese Medicine Cancer HospitalBeijing100023China Department of Hepatic Surgery the Third Affiliated Hospital of Naval Medical UniversityShanghai200433China Department of Abdominal Surgery Cancer Hospital of Chinese Academy of Medical SciencesBeijing100021China Department of Hepatic Surgery the Fifth Medical Center of PLA General HospitalBeijing100161China Department of Hepatic Surgery the First Hospital of Lanzhou UniversityLanzhou730013China Department of Hepatic Surgery Huai’an First People’s HospitalNanjing Medical UniversityHuai’anJiangsu Province223399China Department of Hepatic Surgery PLA Rocket Army General HospitalBeijing100088China Department of Interventional Therapy Shenzhen Hospital of Peking UniversityShenzhenGuangdong Province518036China Department of Hepatic Surgery China-Japan Friendship HospitalBeijing100029China Department of Hepatic Surgery Baotou Central HospitalBaotouInner Mongolia Autonomous Region014042China Department of Traditional Chinese Medicine No.900 Hospital of the Joint Logistics Support Force of PLAFuzhou350025China

Objective:To evaluate the efficacy and safety of Cidan Capsule combined with adjuvant transarterial chemoembolization(TACE) in patients with a high risk of early recurrence after curative resection of hepatocellular carcinoma(HCC).Methods:A multicenter,randomized controlled trial was conducted in patients with high-risk recurrence factors after curative resection of HCC from 9 medical centers between July 2014 and July ***249 patients were randomly assigned to TACE with or without Cidan Capsule administration groups by stratified block in a 1:1 *** adjuvant TACE was given 4-5 weeks after hepatic resection in both ***,125 patients in the TACE plus Cidan group were administrated Cidan Capsule(0.27 g/capsule,5 capsules every time,4 times a day) for 6 months with a 24-month *** endpoints included diseasefree survival(DFS) and tumor recurrence rate(TRR).Secondary endpoint was overall survival(OS).Any drugrelated adverse events(AEs) were observed and ***:As the data cutoff on July 9th,2018,the median DFS was not reached in the TACE plus Cidan group and 234.0 days in the TACE group(hazard ratio,0.420,95%confidence interval,0.290-0.608;Pdan and TACE groups were 31.5%,37.1%,and 60.8%,63.4%,respectively(Pdan and TACE groups were 98.4%,98.4%,and 89.5%,87.9%,respectively(Pdan group,the death was due to retroperitoneal mass hemorrhage and hemorrhagic shock,and was not related to study ***:Cidan Capsule in combination with TACE can reduce the incidence of early recurrence in HCC patients at high-risk of recurrence after radical hepatectomy and may be an appropriate option in postoperative anti-recurrence treatment.(Reg

关键词： hepatocellular carcinoma hepatectomy recurrence survival transarterial chemoembolization Cidan Capsule

High-Order Decoupled and Bound Preserving Local Discontinuous Galerkin Methods for a Class of Chemotaxis Models

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Communications on Applied Mathematics and Computation 2024年第1期6卷 372-398页

作者： wei zheng Yan Xu School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina

In this paper,we explore bound preserving and high-order accurate local discontinuous Galerkin(LDG)schemes to solve a class of chemotaxis models,including the classical Keller-Segel(KS)model and two other density-dependent *** use the convex splitting method,the variant energy quadratization method,and the scalar auxiliary variable method coupled with the LDG method to construct first-order temporal accurate schemes based on the gradient flow structure of the *** semi-implicit schemes are decoupled,energy stable,and can be extended to high accuracy schemes using the semi-implicit spectral deferred correction *** bound preserving DG discretizations are only worked on explicit time integration methods and are difficult to get high-order *** overcome these difficulties,we use the Lagrange multipliers to enforce the implicit or semi-implicit LDG schemes to satisfy the bound constraints at each time *** bound preserving limiter results in the Karush-Kuhn-Tucker condition,which can be solved by an efficient active set semi-smooth Newton *** numerical experiments illustrate the high-order accuracy and the effect of bound preserving.

关键词： Chemotaxis models Local discontinuous Galerkin(LDG)scheme Convex splitting method Variant energy quadratization method Scalar auxiliary variable method Spectral deferred correction method