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Application of phosphate-containing materials affects bioavailability of rare earth elements and bacterial community in soils

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science china(Technological sciences) 2019年第9期62卷 1616-1627页

作者： JIN shuLan HU ZhongJun man BaiYing PAN HuaHua KONG Xiao JIN Decai college of History Geography and TourismShangrao Normal UniversityShangrao 334000China Research center for Eco-Environmental sciences Chinese Academy of SciencesBeijing 100085China

The exploitation and smelting of rare earths can cause serious pollution to the farmland around the mining area. The rare earth elements(REEs) are absorbed by crops and enter the human body through the food chain, which threatens people’s health. The effects of four phosphorus-containing materials-calcium superphosphate(ssP), phosphate rock(PR), calcium magnesium phosphate(cMP) and bone charcoal(Bc) on rice growth and bacterial community structure in REE mining area of Xinfeng county were studied by pot experiment. The soil solution was collected during rice transplanting and harvest periods respectively, the rice and soil samples were collected and sequenced. The concentrations of water-soluble REEs were measured by inductively coupled plasma mass spectrometry(IcP-Ms), and bacteria in soil was deeply sequenced by the Illumina Miseq sequencing platform. PR, cMP and Bc promoted the growth of rice, improved the biomass of rice roots, shoots and grains, and significantly reduced absorption and accumulation of REEs in rice roots, shoots and grains. ssP treatment reduced the pH value of soil, significantly improved the concentration of REE solution in soil and improved biomass of rice roots, shoots and grains,and significantly improved the concentration of REEs in grain. The effects of phosphorus-containing materials on the absorption and accumulation of 15 REEs in rice roots, shoots and grains were very different, and significantly influenced the soil bacterial community. ssP reduced richness and diversity of bacteria. cMP improved the diversity of soil bacteria, but reduced their richness. PR and Bc treatment improved the richness and diversity of soil bacteria, and significantly increased the abundance of Bacillus. The results showed that adding PR, cMP and Bc to soil in the REE mining area of Xinfeng can improve food security and eco-environmental quality, and hence, are potential restorative materials;ssP is not recommended for use in acidic soils.

关键词： calcium superphosphate phosphate rock calcium magnesium phosphorus bone charcoal rare earth elements rice bacterial community

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Vulvar basal cell carcinoma: A retrospective study of 29 cases from Queensland

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Open Journal of Obstetrics and Gynecology 2012年第2期2卷 136-139页

作者： Ian s. c. Jones alex crandon Karen sanday Queensland centre for Gynaecological cancer Royal Brisbane and Women’s Hospital Brisbane Australia

Objective: Review the clinical features, diagnosis, management and outcomes for 29 cases of Basal cell carcinoma (Bcc) of the Vulva referred to Queensland centre for Gynaecological cancer (QcGc) between 1986 and 2010. Methods: Vulvar Bcc cases from QcGc were reviewed and analysed using the computer software statistical Package for the social sciences (sPss) 11.0. Results: Bcc of the vulva is uncommon with an incidence from the QcGc vulvar cancer registry of 3.2%. Of the 29 patients one died of their Bcc and seven died of unrelated causes. The mean age at diagnosis was 69.5 years (range 40 to 91). All cases were caucasian. Time from onset of symptoms to diagnosis averaged 22.6 months (range 0 - 120 months). Not until a biopsy was performed was the diagnosis made. The most common presenting complaints were pruritis and a lump. Initial treatment was surgical. conclusions: The prognosis for vulvar Bcc is excellent. Histological diagnosis and long term follow-up are important management issues. The status of disease at the margins of surgical specimens does not reliably equate to patient long term outcomes. Follow up should be supervised via a gynecological oncology register to reduce the risk of patient loss to follow up.

关键词： Vulvar Basal cell carcinoma Diagnosis management Outcome specimen Margins Follow-Up

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INFRAsTRUcTURE & LOGIsTIcs IN THE NEW GLOBAL EcONOMY

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中国远洋海运 2000年第7期 36-39页

作者： alex c. Yim managing Director FedEx Asia Pacific Hub

Good morning ladies and gentlemen. It’s an honor to be here today. Thank you very much for giving me this opportunity to speak before this distinguished group. Today, I will talk to you about Logistics and Distribution and the importance of FedEx’s role, as a total logistics provider, in global commerce. Before I go on, allow me first to give you a little background about FedEx and our capabilities here in the Asia Pacific Region.

关键词： Bay more LOGIsTIcs IN THE NEW GLOBAL EcONOMY INFRAsTRUcTURE than very

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Robust reinforcement learning with UUB guarantee for safe motion control of autonomous robots

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science china(Technological sciences) 2024年第1期67卷 172-182页

作者： ZHANG RuiXian HAN YiNing sU man LIN ZeFeng LI HaoWei ZHANG LiXian school of Astronautics Harbin Institute of TechnologyHarbin 150001China school of management Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Tracking and Telecommunication Technology Beijing 100094China

This paper addresses the issue of safety in reinforcement learning(RL)with disturbances and its application in the safety-constrained motion control of autonomous *** tackle this problem,a robust Lyapunov value function(rLVF)is *** rLVF is obtained by introducing a data-based LVF under the worst-case disturbance of the observed *** the rLVF,a uniformly ultimate boundedness criterion is *** criterion is desired to ensure that the cost function,which serves as a safety criterion,ultimately converges to a range via the policy to be ***,to mitigate the drastic variation of the rLVF caused by differences in states,a smoothing regularization of the rLVF is *** train policies with safety guarantees under the worst disturbances of the observed states,an off-policy robust RL algorithm is *** proposed algorithm is applied to motion control tasks of an autonomous vehicle and a cartpole,which involve external disturbances and variations of the model parameters,*** experimental results demonstrate the effectiveness of the theoretical findings and the advantages of the proposed algorithm in terms of robustness and safety.

关键词： motion control reinforcement learning robustness stability

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The Drivers of child Mortality During the 2012–2016 Drought in La Guajira, colombia

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International Journal of Disaster Risk science 2020年第1期11卷 87-104页

作者： Diana contreras alex Voets Jana Junghardt srirama Bhamidipati sandra contreras Research center for Integrated Disaster Risk management(cIGIDEN) Pontifical Catholic University of Chile7820436 MaculSantiagoChile school of Engineering Newcastle UniversityNewcastle upon TyneNorthumbria NE17RUUK caritas switzerland BogotaD.C.110231Colombia caritas switzerland 6002 Luzern LucernaSwitzerland Faculty of Technology Policy and ManagementDelft University of Technology2628 BX DelftThe Netherlands communication and Language Pontifical Xavierian UniversityBogotaD.C.110231Colombia

During the 2012–2016 drought in La Guajira,colombia, child mortality rates rose to 23.4 out of *** of these children belonged to the Wayuu indigenous community, the largest and one of the most vulnerable in colombia. At the municipal level, this study found a significant positive correlation between the average child mortality rate and households with a monthly income of less than UsD 100, the number of people without access to health insurance, being part of the indigenous population,being illiterate, lacking sewage systems, living in rural areas, and large households with members younger than5 years old and older than 65 years old. No correlation was found with households without access to a water *** stepwise regression analysis showed that households with a monthly income of less than UsD 100, no members older than 65 years old, but several children younger than5 years old, account for 90.4% of the child mortality *** study concludes that, if inhabitants had had better incomes or assets, as well as an adequate infrastructure,they could have faced the drought without the observed increase in child mortality.

关键词： child mortality climate change Drought socioeconomic vulnerability Water management Wayuu indigenous community

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Thrust characteristics of nano-carbon/Al/oxygenated salt nanothermites for micro-energetic applications

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Defence Technology（防务技术） 2023年第12期30卷 55-69页

作者： Ahmed Fahd alex Baranovsky charles Dubois Jamal chaouki sherif Elbasuney shady shokry chemical Engineering Department Ecole Polytechnique de MontrealMontrealH3C 3A7Canada Energetic Materials and Nanotechnology Research center Technical Research CenterCairo11765Egypt Mechanical and Mechatronics Engineering Department University of WaterlooOntarioN2L 3G1Canada Head of Nanotechnology Research center Military Technical CollegeCairo11767Egypt Laser and Optoelectronics Research center Technical Research CenterCairo11765Egypt

combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KclO_(4)), and different carbon nanomaterials(cNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(cNTs) and nanofibers(cNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(IsP), volumetric impulse(IsV), as well as normalized energy were found to increase notably with cNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and IsPwere maximized in the 5%GO/Al/KclO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). cFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.

关键词： Nanothermites Graphene oxide Reduced graphene oxide carbon nano material Oxygenated salts Laser ignition computational fluid dynamics

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利用雷达差分干涉测量技术获取汶川Ms 8.0地震形变场

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地质科技情报 2009年第6期28卷 119-124页

作者：董玉森 Ge Linlin Hsing-chung chang alex Hay-man Ng 张奎中国地质大学地球科学学院武汉430074 school of surveying and spatial Information system University of New South Wales Sydney 2032 Australia 河南理工大学矿山空间信息技术国家测绘局重点实验室河南焦作454003

利用ENVIsAT/AsAR和ALOs/PALsAR数据,结合两路差分干涉测量技术获得了汶川地震的同震形变信息和震前、震后地面在卫星视线(light of sight,简称LOs)方向上的形变特征。结果表明,汶川地震引起的地面形变范围广,程度大,地震形变沿断层向... 详细信息

利用ENVIsAT/AsAR和ALOs/PALsAR数据,结合两路差分干涉测量技术获得了汶川地震的同震形变信息和震前、震后地面在卫星视线(light of sight,简称LOs)方向上的形变特征。结果表明,汶川地震引起的地面形变范围广,程度大,地震形变沿断层向北北东向扩展,所形成的差分干涉条纹明显。地面的形变特征对于推断断层的性质,研究地震形变和地震发育特征具有重要的参考价值。另外,将同震雷达差分干涉测量的结果与利用UsGs发布的汶川地震有限元断层模型(finite fault model)反演的LOs方向的形变进行了对比验证,发现二者在断裂带的上盘具有较好的一致性,但在下盘却有较大的误差。通过不同传感器干涉结果的对比发现,L波段的雷达干涉结果更能够反映汶川大地震在龙门山断裂带附近的地面形变信息。

关键词：雷达差分干涉测量技术汶川地震地面形变

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Nc code generation for laser assisted turn-mill of various type of clovers and square section members

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Journal of central south University 2012年第11期19卷 3064-3068页

作者： cHOI Jun-young LEE choon-man Department of Mechanical Design & manufacturing Engineering Changwon National UniversityChangwon 641-773Korea

Laser assisted turning （LAT） is one of the advanced machining technologies, which uses laser power to heat the surface of a workpiece before the material is removed. It has several advantages of low manufacturing costs, high productivity and high qualities to machine difficult-to-cut materials such as silicon nitride, muUite, zirconia and Ni. A large part of studies on LAT have been focused on a round bar. With increasing demands for high quality products and high performance engineering system, the researches on LAT for clover and square section members are necessary. But, these workpieces are impossible to be machined on conventional cNc lathe and to generate Nc code with current cAM softwares. As a basic research for combining LAT with a tilting index table type 5-axis machining center, i.e. laser assisted turn-mill, a new method is suggested to generate Nc code that can process various types of clover and square section members through development of c＋＋ program.

关键词： laser assisted turning (LAT) Nc code clover section turn-mill square section turn-mill

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A Facile Route to synthesize sheet-like Na2Ti3O7 with Improved sodium storage Properties

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chemical Research in chinese Universities 2015年第3期31卷 443-446页

作者： XIE man WANG Kangkang cHEN Renjie LI Li WU Feng Beijing Key Laboratory of Environmental science and Engineering School of Chemical Engineering and Environment National Development center of High Technology Green Materials Beijing Institute of Technology Beijing 100081 P. R. China

A high purity sheet-like Na2Ti307 material was synthesized by a new facile solid-state method with hollow sphere TiO2 as titanium source. X-Ray diffraction（XRD） measurement proves that no impurity phase existed when the sample was heated at 900 ℃. charge/discharge measurement was performed in a potential range of 0.01m2.5 V at different current-rates（c-rates）. The initial charge/discharge capacities are 191/424 mA.h/g at 0.1 c and still remain as high as 101 mA.h/g after 50 cycles. cV test proves that the large irreversible capacity in the initial cycle results from the formation of the solid electrolyte interface（sEI）. However, the electrode presents an increased initial cou- lombic efficiency in a 1 mol/L NaPF6 electrolyte compared to that in a 1 mol/L NacIO4 electrolyte.

关键词： Na2Ti307 sodium-ion battery Anode Hollow sphere TiO2

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Influence of notch volume on mechanical properties of a novel high-strength and high-toughness steel

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Journal of Iron and steel Research International 2023年第12期30卷 2482-2493页

作者： Zhi-gang Tao Ke Qin shu-lin Ren Hao-tian Xu man-chao He state Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing100083China school of Mechanics and civil Engineering China University of Mining and Technology(Beijing)Beijing100083China

The effect of notch volume on the mechanical behavior of a novel high-strength and high-toughness steel with negative Poisson’s ratio effect(called NPR steel)was ***,the quasi-static tensile test of NPR steel with different notch volumes was carried out,and its failure characteristics and mechanical properties parameters were ***,the modified Johnson-cook(J-c)constitutive model with coupled notch volume ratio was *** model was validated based on three-dimensional finite element numerical *** results show that the engineering stress–strain curve of NPR steel has no yield platform,and has the mechanical properties of high strength,high elongation,and high energy *** volume significantly affects the mechanical properties of NPR *** elongation,yield strength,tensile strength,and energy absorption characteristics of steel bar gradually decrease with the increase in notch *** notch volume ratio V^{*},a characteristic parameter describing the notch volume of reinforcement,is defined,and the quantitative relationship between this parameter and mechanical parameters is established,which can accurately characterize the mechanical properties of specimens with different notch volume *** on the true stress–strain curves with different notch volume ratios,a constitutive model with modified Johnson-cook model parameters is *** finite element results show that the modified J-c model can accurately fit the quasi-static tensile mechanical behavior of NPR steel.

关键词： High-strength and high-toughness steel Negative Poisson's ratio effect Tensile experiment Notch volume ratio Johnson-cook constitutive model

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