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基于光谱技术的典型互花米草入侵湿地土壤属性预测研究

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光谱学与光谱分析 2025年第1期45卷 197-203页

作者：陈旭曹思珩杨仁敏陈秋宇李建国徐璐 4 江苏师范大学地理测绘与城乡规划学院地理信息科学系江苏徐州221116

为了高效监测互花米草入侵海岸带湿地生态系统的土壤属性变化,选取江苏省盐城湿地珍禽国家级自然保护区的一处典型互花米草入侵湿地作为研究区,利用随机分层采样方法选取15个样点,在3个深度(0~30、30~60、60~100 cm)共采集45个土壤样品... 详细信息

为了高效监测互花米草入侵海岸带湿地生态系统的土壤属性变化,选取江苏省盐城湿地珍禽国家级自然保护区的一处典型互花米草入侵湿地作为研究区,利用随机分层采样方法选取15个样点,在3个深度(0~30、30~60、60~100 cm)共采集45个土壤样品,测定了土壤可见光-近红外反射光谱和10种土壤理化属性,研究了偏最小二乘和随机森林两种方法的预测能力,分析了不同光谱变换形式对预测精度的影响,探讨了入侵年限和土壤深度作为辅助预测变量的潜力。结果表明:(1)可见光-近红外光谱技术可以较好地预测有机碳、无机碳、全氮、含水量、pH、容重、盐分和黏粒等属性;(2)偏最小二乘回归法比随机森林法更适合监测互花米草入侵湿地的关键土壤理化属性,利用偏最小二乘法对土壤属性建立的预测模型精度(R^(2))在0.341~0.979之间,随机森林方法对土壤属性建立的预测模型精度(R^(2))最高为0.722;(3)基于原始光谱可以获得土壤全氮的最优预测模型(R^(2)为0.769,RMSE为0.091 g·kg^(-1)),而其他土壤属性的最优模型多是基于微分变换或倒数变换建立的模型,微分变换和倒数变换可以有效地提高模型预测精度;(4)模型预测精度在加入入侵年限和土壤深度两个变量后总体上有所提高,其中有机碳、全氮、盐分、pH和容重等属性的预测精度对这两个变量更为敏感,土壤有机碳最优模型的精度(R^(2))从0.794提高到0.806,pH最优模型的精度(R^(2))从0.838提升至0.884,盐分最优模型的精度(R^(2))从0.978提升至0.997。综上所述,可见光-近红外光谱技术在互花米草入侵湿地关键土壤理化属性预测方面具有明显的优越性,通过适当的光谱变换、变量筛选、模型选择等方面可以实现互花米草入侵湿地土壤变化的快速监测。

关键词：互花米草入侵可见光-近红外光谱土壤监测偏最小二乘法随机森林光谱变换

Hydrogen Embrittlement of Advanced High-Strength Steel for Automobile Application:A Review

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Acta Metallurgica Sinica(English Letters) 2023年第7期36卷 1144-1158页

作者： ming-Tu Ma ke-jian li yu Si Peng-Jun cao Hong-Zhou Lu Ai-min guo guo-Dong Wang State key Laboratory of Vehicle NVH and Safety Technology Chongqing 401122China China Automotive Engineering Research Institute Co. Ltd.Chongqing 401122China School of Metallurgy and Materials Engineering Chongqing University of Science&TechnologyChongqing 401331China CITIC Metal Co.Ltd Beijing 100004China RAL of Dongbei University Shenyang 110819China

The hydrogen embrittlement(HE)fracture of advanced high-strength steels used in lightweight automobiles has received increasing public *** source,transmission,and movement of hydrogen,characterization parameters,and test methods of HE,as well as the characteristics and path of HE fractures,are *** mechanisms and modes of crack propagation of HE and hydrogen-induced delayed fracture are *** recent progress surrounding micro and macro typical fracture characteristics and the influencing factors of HE are ***,methods for improving HE resistance can be summarized as follows:(1)reducing crystalline grain and inclusion sizes(oxides,sulfides,and titanium nitride),(2)controlling nano-precipitates(niobium carbide,titanium carbide,and composite precipitation),and(3)increasing residual austenite content under the reasonable tension strength of steel.

关键词： Hydrogen embrittlement High-strength steel Hydrogen-induced delayed cracking Hydrogen trapping Residual austenite

Interactions between phosphorus availability and microbes in a wheat–maize double cropping system:A reduced fertilization scheme

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Journal of Integrative Agriculture 2022年第3期21卷 840-854页

作者： yu Xiao-jing CHEN Qi SHI Wen-cong GAO Zheng SUN Xiao DONG jing-jing li Juan WANG heng-tao GAO jian-guo liU Zhi-guang zhang min National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources/College of Resources and Environment/College of life Sciences Shandong Agricultural UniversityTai’an 271018P.R.China key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China Shandong Zhongxin Agricultural Development Co. Ltd.Linshu 276700P.R.China

Mechanisms controlling phosphorus(P) availability and the roles of microorganisms in the efficient utilization of soil P in the wheat–maize double cropping system are poorly *** the present study,we conducted a pot experiment for four consecutive wheat–maize seasons(2016–2018) using calcareous soils with high(30.36 mg kg^(–1)) and low(9.78 mg kg^(–1)) initial Olsen-P content to evaluate the effects of conventional P fertilizer application to both wheat and maize(Pwm) along with a reduced P fertilizer application only to wheat(Pw).The microbial community structure along with soil P availability parameters and crop yield were *** results showed that the Pw treatment reduces the annual P input by 33.3% without affecting the total yield for at least two consecutive years as compared with the Pwm treatment in the high Olsen-P *** water-soluble P concentrations in the Pw treatment were similar to those in the Pwm treatment at the 12-leaf collar stage when maize requires the most ***,the soil P content significantly affected soil microbial communities,especially fungal ***,the relative abundances of Proteobacteria and alkaline phosphatase(ALP) activity of Pw were significantly higher(by 11.4 and 13.3%) than those of Pwm in soil with high *** microfloral contribution to yield was greater than that of soil P content in soil with high *** abundances of Bacillus and Rhizobium were enriched in the Pw treatment compared with the Pwm *** showed a significant positive correlation with acid phosphatase(ACP) activity,and Rhizobium displayed significant positive correlations with ACP and ALP in soil with high Olsen-P,which may enhance P *** findings suggested that the application of P fertilization only to wheat is practical in high P soils to ensure optimal production in the wheat and maize double cropping system and that the soil P availability and microbial community may collabo

关键词： wheat–maize rotation Olsen-P alkaline phosphatase phosphorus fertilization calcareous soils

Spherical nanoindentation stress–strain responses of SIMP steel to synergistic effects of irradiation by H and He ions

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Nuclear Science and Techniques 2022年第6期33卷 139-147页

作者： Peng Jin Tie-Long Shen jing li yu-Shan Yang jian-Long Chai Ya-bin Zhu ming-Huan Cui Chao liu Tong-min zhang Long Kang Jun li Jin-yu li Shuo-xue Jin Xing-Zhong cao Zhi-Guang Wang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

A novel Fe-10Cr ferritic/martensitic steel called SIMP was chosen to investigate synergistic effects of H and He on the mechanical properties of structural materials for innovative nuclear energy systems. Sequential and separate irradiation experiments on SIMP steel specimens at room temperature using H and He ions with various energy levels were conducted to produce an ion deposition plateau at 300-650 nm. The indentation stress-strain responses were examined using spherical nanoindentation tests after the irradiation experiments. It was found that the sequential irradiation by He and H produced a higher indentation yield stress than separate irradiation, indicating that the hardening was enhanced by the synergy of the H and He irradiation. The micro-mechanism responsible for enhancing the hardening of the SIMP steel through the H and He synergy was investigated using Doppler broadening spectroscopy detection and transmission electron spectroscopy observations.

关键词： H/He irradiation Spherical nanoindentation Bubbles Dislocation loops

Experimental entanglement quantification for unknown quantum states in a semi-device-independent manner

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Science China(Information Sciences) 2023年第8期66卷 72-79页

作者： yu guo lijinzhi liN Huan cao Chao zhang Xiaodie liN Xiao-min HU Bi-heng liU yun-Feng HUANG Zhaohui WEI Yong-jian HAN Chuan-Feng li Guang-Can guo CAS key Laboratory of Quantum Information University of Science and Technology of China CAS Center For Excellence in Quantum Information and Quantum Physics University of Science and Technology of China School of Physics and Materials Engineering Hefei Normal University Center for Quantum Information Institute for Interdisciplinary Information Sciences Tsinghua University Vienna Center for Quantum Science and Technology Faculty of Physics University of Vienna Yau Mathematical Sciences Center Tsinghua University

Using the concept of non-degenerate Bell inequality, we show that quantum entanglement, the critical resource for various quantum information processing tasks, can be quantified for any unknown quantum state in a semi-device-independent manner, where the quantification is based on the experimentally obtained probability distributions and prior knowledge of the quantum dimension only. Specifically, as an application of our approach to multi-level systems, we experimentally quantify the entanglement of formation and the entanglement of distillation for qutrit-qutrit quantum systems. In addition, to demonstrate our approach for multi-partite systems, we further quantify the geometric measure of entanglement of three-qubit quantum systems. Our results supply a general way to reliably quantify entanglement in multi-level and multi-partite systems, thus paving the way to characterize many-body quantum systems by quantifying the involved entanglement.

关键词： entanglement quantification semi-device-independent bell nonlocality multi-partite system multi-level system

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Diagnosis and treatment of acute graft-versus-host disease after liver transplantation:Report of six cases

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World Journal of Clinical Cases 2021年第30期9卷 9255-9268页

作者： min Tian Yi Lyu Bo Wang chang liu liang yu jian-Hua Shi xue-min liu Xiao-Gang zhang Kun guo yu li liang-Shuo Hu Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

BACKGROUND Graft-versus-host disease(GVHD)following liver transplantation(LT)is an unpredictable complication with poor ***,consensus regarding the diagnosis and therapeutic regimen for the disease is yet *** present study summarized the clinical experience on the diagnosis and treatment of acute GVHD(aGVHD)following LT and reviewed the pertinent *** SUMMARY Between January 1^(st),2000 and December 31^(st),2020,a total of 1053 LT were performed in the First Affiliated Hospital of Xi’an Jiaotong *** recipients developed aGVHD with clinical symptoms of fever,rash,diarrhea,and *** incidence of aGVHD was 0.57%.The median time from LT to the clinical presentation of aGVHD was 22.17 *** median time from the beginning of the clinical symptom to histopathological diagnosis was 7.5 *** six cases underwent treatment of immunosuppressant adjustment,corticosteroids,human normal immunoglobulin,and antithymocyte globulin/IL-2 *** intensive treatment strategies,4 patients were deceased due to sepsis,multiple organ failure,and cerebral *** remaining two cases were discharged as treatment ***,one died because of tuberculosis infection on the 6 th month of follow-up,the other one was alive healthy during 30 mo of *** The rapid diagnosis of aGVHD is mainly based on the time from the first symptom,histopathological features,and the donor T-lymphocyte *** cases report highlights massive corticosteroid therapy and age difference between donors and recipients could accelerate to ***,gut microbial interventions and donor-targeted serotherapy may provide novel therapeutics.

关键词： Graft-versus-host disease liver transplantation Donor T-lymphocytes chimerism Gut microbiota Donor-targeted serotherapy Case report

A Cd-based MOF crystal vessel for the synthesis of interhalogens

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Chinese Journal of Structural Chemistry 2023年第9期42卷 18-25页

作者： min-Jie zhang yu Ge Chen cao Xin-Ran xue Qiu-Yi li Qi liu jian-Ping Lang College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu215123People's Republic of China State key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032People's Republic of China

As important halogenating and oxidant agents,the synthesis and utilization of interhalogens are plagued by their purity problem,strong volatility and high ***,a flexible Cd-based metal-organic framework(MOF),{[Cd(1,4-bdc)(4-bpa)]·DMF}_(n)(1,where 4-bpa=1,2-bis(4-pyridyl)acetylene),was prepared and its corresponding activation species,[Cd(1,4-bdc)(4-bpa)]_(n)(2),with moderate pore size and shape,acting as a crystal vessel,was applied to synthesize and store pure *** synthesis of interhalogen was realized by quantitive transformation of halogen molecules incorporated in the pores of 2,which was confirmed by single-crystal X-ray diffraction and other structural *** embedded interhalogen molecules were stabilized by their interactions with the inner groups of the porous framework of 2 and released in polar solvent and utilized in iodocyclization of organic alcohols with high *** work not only opens a new door to the synthesis of pure interhalogens but also demonstrates powerful applications of MOF crystal vessels in realizing classic but important inorganic and organic reactions.

关键词： MOFs Crystal vessel Interhalogens Crystal structures Iodocyclization

A mini review on oxidative dehydrogenation of propane over boron nitride catalysts

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Petroleum Science 2023年第4期20卷 2488-2498页

作者： Zhu Fu De-Zheng li li-Dai Zhou yu-ming li Jia-Wen guo yu-Qiao li Hui-min liu Qi-jian zhang School of Chemical and Environmental Engineering Liaoning University of TechnologyJinzhouLiaoning121001China State key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China

Oxidative dehydrogenation of propane is an attractive route for the synthesis of propylene due to its favorable thermodynamic and kinetic characteristics, however, it is challenging to realize high selectivity towards propylene. Recently, it has been discovered that boron nitride (BN) is a promising catalyst that affords superior selectivity towards propylene in oxidative dehydrogenation of propane. Summarizing the progress and unravelling the reaction mechanism of BN in oxidative dehydrogenation of propane are of great significance for the rational design of efficient catalysts in the future. Herein, in this review, the underlying reaction mechanisms of oxidative dehydrogenation of propane over BN are extracted;the developed BN catalysts are classified into pristine BN, functionalized BN, supported BN and others, and the applications of each category of BN catalysts in oxidative dehydrogenation of propane are summarized;the challenges and opportunities on oxidative dehydrogenation of propane over BN are pointed out, aiming to inspire more studies and advance this research field.

关键词： Oxidative dehydrogenation of propane Boron nitride Propylene Reaction mechanism

Recent advances on the nitrogen-rich 1,2,4-oxadiazole-azoles-based energetic materials

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Defence Technology（防务技术） 2022年第3期18卷 344-367页

作者： Wen-li cao Qamar-un-Nisa Tariq Zhi-min li Jun-Qing Yang jian-guo zhang State key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081 PR China CAS key Laboratory of Energy Regulation Materials Shanghai200032China

This review covers recent advances in the synthesis and energetic performance of nitrogen-rich 1,2,4-oxadiazole-azoles-based energetic *** materials comprise of 1,2,4-oxadiazole subunit as a key structural motif linked to different nitrogen-rich or nitrogen-oxygen azoles:tetrazole,furazan,furoxan,1,3,4-oxadiazole,pyrazole,and *** attention is devoted to the introduction of various energetic groups including nitro,nitramino,azo,azoxy,dinitromethyl,trinitroethyl moieties,and their *** physicochemical and available performance parameters including density,decomposition temperature,heat of formation,detonation pressure,detonation velocity,impact sensitivity,and friction sensitivity of typical energetic compounds are also provided and ***,it was obtained that several screened compounds exhibit superior detonation properties and outstanding insensitivities,which can be classified as a new family of high-performance energetic ***,1,2,4-oxadiazole-azoles-based energetic materials still have many thorough works to further exploited and studied,expecting to get very promising insensitive high explosives for practical application and industrialization.

关键词： 1,2,4-Oxadiazole-azoles Triazole Tetrazole Furazan Energetic materials Furoxan