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Influence of TiO2 on the melting property and viscosity of Cr-containing high-Ti melting slag

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 310-318页

作者： jing Ma Gui-qin Fu wei Li Miao-yong Zhu School of Metallurgy Northeastern University

A study on the melting and viscosity properties of the chromium-containing high-titanium melting slag(CaO–SiO2–MgO–Al2O3–TiO2–Cr2O3) with TiO2 contents ranging from 38.63 wt% to 42.63 wt% was conducted. The melting properties were investigated with a meltingpoint apparatus, and viscosity was measured using the rotating cylinder method. The FactSage 7.1 software and X-ray diffraction, in combination with scanning electron microscopy–energy-dispersive spectroscopy(SEM–EDS), were used to characterize the phase equilibrium and microstructure of chromium-containing high-titanium melting slags. The results indicated that an increase in the TiO2 content led to a decrease in the viscosity of the chromium-containing high-titanium melting slag. In addition, the softening temperature, hemispheric temperature, and flowing temperature decreased with increasing TiO2 content. The amount of crystallized anosovite and sphene phases gradually increased with increasing TiO2 content, whereas the amount of perovskite phase decreased. SEM observations revealed that the distribution of the anosovite phase was dominantly influenced by TiO2.

关键词： titanium dioxide Cr-containing high-titanium melting slag melting property viscosity vanadium titanomagnetite

Autonomous maneuver decision-making for a UCAV in short-range aerial combat based on an MS-DDQN algorithm

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Defence Technology（防务技术） 2022年第9期18卷 1697-1714页

作者： yong-feng Li jing-ping Shi wei Jiang wei-guo Zhang yong-xi Lyu School of Automation Northwestern Polytechnical UniversityXi'an 710129China Shaanxi Province Key Laboratory of Flight Control and Simulation Technology Xi'an 710129China

To solve the problem of realizing autonomous aerial combat decision-making for unmanned combat aerial vehicles(UCAVs) rapidly and accurately in an uncertain environment, this paper proposes a decision-making method based on an improved deep reinforcement learning(DRL) algorithm: the multistep double deep Q-network(MS-DDQN) algorithm. First, a six-degree-of-freedom UCAV model based on an aircraft control system is established on a simulation platform, and the situation assessment functions of the UCAV and its target are established by considering their angles, altitudes, environments, missile attack performances, and UCAV performance. By controlling the flight path angle, roll angle, and flight velocity, 27 common basic actions are designed. On this basis, aiming to overcome the defects of traditional DRL in terms of training speed and convergence speed, the improved MS-DDQN method is introduced to incorporate the final return value into the previous steps. Finally, the pre-training learning model is used as the starting point for the second learning model to simulate the UCAV aerial combat decision-making process based on the basic training method, which helps to shorten the training time and improve the learning efficiency. The improved DRL algorithm significantly accelerates the training speed and estimates the target value more accurately during training, and it can be applied to aerial combat decision-making.

关键词： Unmanned combat aerial vehicle Aerial combat decision Multi-step double deep Q-network Six-degree-of-freedom Aerial combat maneuver library

Enhanced thermoelectric properties of Zintl phase YbMg_(2)Bi1.98 through Bi site substitution with Sb

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Journal of Materials Science & Technology 2020年第24期59卷 189-194页

作者： jing Wang Muchun guo Jianbo Zhu Dandan qin Fengkai guo Qian Zhang wei Cai Jiehe Sui National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin150001China Department of Materials Science and Engineering Harbin Institute of TechnologyShenzhenShenzhen518055China

Benefiting from the unique"Phonon-Glass,Electron-Crystal"(PGEC)characteristic,Zintl phases have been considered as a kind of promising thermoelectric *** the typical AM2X2 compounds with the CaAl2Si2-type structure,YbMg_(2)Bi2 has shown competitive thermoelectric performance ***,the optimization of YbMg_(2)Bi2 compounds is primarily focused on the substitution on Yb or Mg ***,the Bi site is substituted by isoelectric Sb and the effect on the thermoelectric transport behavior is *** partial substitution reduces the carrier concentration and induces the lattice deformation caused by the different atomic radius and mass between Bi and Sb,further leading to the decreased power factor and thermal ***,the reduction extent of the thermal conductivity outperforms that of power ***,the Sb substitution successfully results in a better thermoelectric performance compared with that of the pristine YbMg_(2)***,the calculated energy conversion efficiency(a)of YbMg_(2)Bi1.88Sb0.1 which also possesses a relatively high output power density reaches the maximum value of 9.8% when Th=873 K,and Tc=300 K,*** work demonstrates that the idea of substitution on anionic site should be a new strategy to achieve better ZT values for AM2X2 compounds.

关键词： Zintl phase YbMg_(2)Bi2 Anionic substitution Thermoelectric properties

Environmental factors controlling soil warming and wetting during 2000-2020 in permafrost and non-permafrost regions across the qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第2期15卷 285-296页

作者： guo-An yin jing LUO Fu-Jun NIU Ming-Hao LIU Ze-yong GAO Tian-Chun DONG wei-Heng NI State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway qinghai-Tibet Group Co. Ltd.Xining 810000China University of Chinese Academy of Sciences Beijing 100049China

The qinghai-Tibet Plateau(QTP)has experienced rapid environmental changes,including climate warming and wetting,since the *** environmental changes significantly impact the shallow soil hydrothermal conditions,which have key roles in land-atmosphere feedback and ecosystem ***,the spatial variations and responses of soil hydrothermal conditions to environmental changes over the QTP with permafrost(PF)and seasonal frost(SF)remain *** this study,we investigated the spatial variations in soil temperature(ST)and soil moisture(SM)changes over the QTP from 2000 to 2020 using 99 in-situ sites with observations at 4 depths(i.e.10,40,100 and 200 cm).The main environmental controlling factors were further identified using a calibrated statistical *** showed that significant(p<0.05)soil warming occurred at multiple soil layers during 2000-2020 with a wide variation(i.e.0.033-0.039℃ per year on average),whereas the warming rates at PF sites were two times greater than those at SF *** addition,the soil wetting rate was high over the SF region,whereas the soil wetting rate was low over the PF *** from air temperature,changes in thawing degree days and solar radiation(Srad)contributed most to soil warming in the PF region,whereas changes in rainfall,Srad and evaporation(EVA)have been identified as the key factors in the SF *** for soil wetting,changes in snowfall,freezing degree days and vegetation have noticeable nonlinear effects over the PF region,whereas changes in EVA,Srad and rainfall highlighted distinct linear and nonlinear effects in the SF *** findings enhance our understanding of the hydrothermal impacts of future environmental changes over the QTP.

关键词： Warming amd wetting Soil hydrothermal change Factor Permafrost Seasonal frost

Experimental verification of generalized eigenstate thermalization hypothesis in an integrable system

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Light(Science & Applications) 2022年第7期11卷 1615-1624页

作者： qin-qin Wang Si-jing Tao wei-wei Pan Zhe Chen Geng Chen Kai Sun Jin-Shi Xu Xiao-Ye Xu yong-Jian Han Chuan-Feng Li Guang-Can guo CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Identifying the general mechanics behind the equilibration of a complex isolated quantum system towards a state described by only a few parameters has been the focus of attention in non-equilibrium *** several experimentally unproven conjectures are proposed for the statistical description of quantum(non-)integrable *** plausible eigenstate thermalization hypothesis(ETH),which suggests that each energy eigenstate itself is thermal,plays a crucial role in understanding the quantum thermalization in non-integrable systems;it is commonly believed that it does not exist in integrable ***,integrable systems can still relax to the generalized Gibbs *** a microscopic perspective,understanding the origin of this generalized thermalization that occurs in an isolated integrable system is a fundamental open question lacking experimental ***,we experimentally investigated the spin subsystem relaxation in an isolated spin-orbit coupling quantum *** applying the quantum state engineering technique,we initialized the system with various distribution widths in the mutual eigenbasis of the conserved ***,we compared the steady state of the spin subsystem reached in a long-time coherent dynamics to the prediction of a generalized version of ETH and the underlying mechanism of the generalized thermalization is experimentally verified for the first *** results facilitate understanding the origin of quantum statistical mechanics.

关键词： integrable quantum state

Processing and oxidation behavior of Pt-diffused coatings

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Rare Metals 2020年第8期39卷 902-908页

作者： Liang-Liang wei Hui Peng Lei Zheng jing-yong Sun Hong-Bo guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of Aerospace Materials and Performance(Ministry of Education) Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China

Pt-diffused coatings were synthesized on Ni10 Al alloy by electroplating a thin layer of Pt(1-5μm)followed by a diffusion treatment in vacuum at 1000-1100℃.Effects of processing parameters(Pt thickness and vacuum diffusion temperature)on the microstructures and chemical composition of Pt-diffused coatings were ***,the oxidation behavior of the coatings was studied at1100℃.Pt film reveals nano-sized grain size of 93-113 *** diffusion treatment leads to the grain growth.1-μm Pt film with 1000℃/1 h vacuum diffusion fabricates nano-sized Pt-diffused coating which exhibits the best oxidation *** a single continuous Al2O3 scale forms on the coating with low Al(~9 at%)and Pt(~6 at%)*** initial Pt thickness would introduce more defects and cracks,leading to a duplex scale and decreasing the oxidation resistance of Ptdiffused coatings.

关键词： Platinum-modifiedγ+γ′coatings Pt-diffused coatings Electroplating Oxidation Nano-structure

Berberine hydrochloride alleviates chronic prostatitis/chronic pelvic pain syndrome by modifying gut microbiome signaling

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Asian Journal of Andrology 2024年第5期26卷 500-509页

作者： Yi-Qun Tian Xiang Ren jing Wang Xing Li Yi-Sheng yin Zi-Hao guo Zhen-Liang qin Xiao-yong Zeng Department of Urology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Institute of Urology of Hubei Province Wuhan 430000China

Chronic prostatitis/chronic pelvic pain syndrome(CP/CPPS)is highly prevalent worldwide and poses a significant threat to men’s health,particularly affecting young ***,the exact causes and mechanisms behind CP/CPPS remain unclear,leading to challenges in its *** this research,a CP/CPPS rat model was established with complete Freund’s adjuvant(CFA),and berberine hydrochloride was administered through daily gavage to assess its therapeutic *** alterations in the gut microbiome induced by CP/CPPS and berberine hydrochloride were investigated through 16S ribosomal RNA sequencing of cecum content and colonic epithelial *** investigate the impact of the gut microbiome on CP/CPPS,a pseudo germ-free rat model was established,and fecal microbiome transplantation(FMT)was performed on these *** all,berberine hydrochloride demonstrated effective reduction of inflammation and oxidative stress in the prostate,offering significant therapeutic advantages for CP/*** analysis of the gut microbiome using 16S ribosome RNA sequencing,distinct differences were observed between CP/CPPS rats and control rats,and Clostridium butyricum was identified as a key *** germ-free rats that underwent FMT from CP/CPPS rats or rats treated with berberine hydrochloride displayed varying levels of inflammatory cytokine production,oxidative stress,and activity of associated signaling *** conclusion,the therapeutic potential of berberine hydrochloride in addressing CP/CPPS is highly *** gut microbiome has emerged as a critical factor in the development of CP/CPPS and plays a pivotal role in mediating the therapeutic effects of berberine hydrochloride.

关键词： berberine hydrochloride chronic prostatitis/chronic pelvic pain syndrome gut microbiome

Schwannomatosis patient who was followed up for fifteen years:A case report

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World Journal of Clinical Cases 2022年第20期10卷 6981-6990页

作者： Kai Li Si-jing Liu Huai-Bo Wang Chang-Yu yin yong-Sheng Huang wei-Tao guo Department of Spine Surgery The Second Hospital affiliated to Guangdong Medical UniversityZhanjiang 524000Guangdong ProvinceChina

BACKGROUND Schwannomatosis is a rare disease characterized by multiple schwannomas of the whole *** benign,schwannomatosis that occurs in important areas of the body,such as the brain and spinal canal,can cause considerable disability and *** disease is rare,frequent and relapsing,and this poses a diagnostic and therapeutic *** SUMMARY A 40-year-old male had multiple masses all over his body,starting at the age of *** years prior,he started to experience a progressive decrease in muscle strength in both lower limbs and developed urinary and defecation dysfunctions,and gradual *** month prior,the patient developed pain and numbness in his left *** patient had undergone five surgical procedures for this disease in our *** on the family history,imaging examinations,pathological biopsy and molecular biological examinations,the diagnosis of schwannomatosis was *** time,the patient was admitted to our hospital again for a 6th operation because of the pain and numbness in his left *** the operation,the patient's symptoms improved significantly;the patient recovered and was discharged from the *** the last telephone follow-up,the patient reported a poor general condition but was *** Here,we report a rare case of *** conducted 15 years of patient follow-up and treatment,and analyzed the timing of surgery and patient *** case will further extend our overall understanding of the diagnosis and treatment of this rare tumor.

关键词： Schwannomatosis Pathogenesis Clinical symptoms Diagnosis Treatment Case report

Microstructure and Nano-hardness of Pure Copper and ODS Copper Alloy under Au Ions Irradiation at Room Temperature

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Acta Metallurgica Sinica(English Letters) 2016年第11期29卷 1047-1052页

作者： jing Zhang yong-qin Chang Zhi-Meng guo Ping-Ping Liu Yi Long Fa-Rong Wan School of Materials Science and Engineering University of Science and Technology Beijing

The microstructure and nano-hardness of the pure copper and oxide dispersion-strengthened（ODS） copper alloy subjected to 1.4 Me V Au ions irradiation at room temperature were investigated. After irradiation, dislocation-loops form in both materials, while voids can only be generated in the pure copper. Compared with the irradiated pure copper, larger average diameter and lower number density of irradiation-induced dislocation-loops were detected in the ODS copper alloy, revealing that high-density dislocation and large volume of Al2O3 particles existing in the ODS copper alloy can act as effective sinks for the irradiation-induced defects. It was also detected that irradiation hardening in the ODS copper alloy is lower than that in the pure copper. The microstructure and nano-hardness results reveal that the ODS copper alloy has a better irradiation tolerance than the pure copper. In addition, the average diameter of the Al2O3 particles in the ODS copper alloy decreases after irradiation, because the Al–O chemical bonds are decomposed and the atoms are redistributed in the matrix during the irradiation process. This work reveals that the irradiation tolerance of the copper can be effectively enhanced by adding nano-sized Al2O3 particles into the matrix.

关键词： Oxide dispersion-strengthened copper alloy Ions irradiation Microstructure evolution Nano-hardness