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Photoluminescence Quenching of Porous Silicon by Molecule Adsorption

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Chinese Physics Letters 1998年第10期15卷 756-757页

作者： LI xue-ping YIN Feng ZHANG Zhen-zong XIAO Xu-rui Institute of Photographic Chemistry Chinese Academy of SciencesBeijing 100101

The photoluminescence of HNO3 chemically oxidized porous silicon can be easily quenched by organic adsorbates,and the ability of quenching was quantitatively estimated by two models-Langmuir adsorption isotherm and Stern-Volmer.A strong steric effect of organic adsorbates on the photoluminescence quenching of oxidized porous silicon was observed.

关键词： quenching oxidized Adsorption

Cementing Properties of Oil Shale Ash

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Journal of China University of Mining and Technology 2007年第4期17卷 498-502页

作者： FENG Xiang-peng NIU xue-lian BAI xue LIU Xiao-ming SUN heng-hu Department of Materials Science and Engineering Tsinghua University Beijing 100084 China School of Resource and Safety Engineering China University of Mining ＆ Technology Beijing 100083 China

The oil crisis has prompted renewed interest in direct burning of oil shale as an alternative energy source. A major problem in this process is the large portion of ash produced. The cementing properties of this ash were investi-gated to determine its applicability as a building material. By means of XRD,IR,NMR and ICP,we have studied the effects of burning temperature on the reactivity of ash. Maximum reactivity was obtained with ash samples produced at 700℃ to 900℃. In this range,the strength of oil-shale-based material,with properties similar to cement,which is composed of oil shale and several other kinds of solid wastes,can achieve the standard of 42.5^# cement. Our study has provided an experimental foundation and theoretical base for a massive utilization of oil shale.

关键词： oil shale thermal activation cementitious activity

Observation of New Nuclide ^(239)Pa

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Chinese Physics Letters 1996年第12期13卷 896-898页

作者： YUAN Shuang-gui YANG Wei-fan MOU Wan-tong ZHANG xue-qian LI zong-wei Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000

A new nuclide ^(239)Pa was produced by 50MeV/u ^(18)O bombardment of natural uranium via multi-nucleon transfer reactions(^(238)U-lp+2n).Protactinium was chemically separated from the uranium target and other produced *** in that chemical fraction the growth and decay of ^(239)U gamma rays were observed,identifying the ^(239)U parent as ^(239)*** to ^(239)Pa β^(-) decay,with a half-life of 106±30min,gamma rays of 522.0,562.0,638.5 and 681.0keV were also observed.

关键词： MeV/u decay separated

Medium oxygen enriched blast furnace with top gas recycling strategy

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Journal of Iron and Steel Research International 2017年第8期24卷 778-786页

作者： Wei Zhang Zheng-liang xue Ju-hua Zhang Wei Wang Chang-gui Cheng zong-shu Zou The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina School of Metallurgy Northeastern UniversityShenyang 110004LiaoningChina

Top gas recycling oxygen blast furnace（TGR-OBF）process is a promising ironmaking *** biggest challenge of the TGR-OBF in operation is the dramatic decrease of top gas volume（per ton hot metal）,which once led to hanging-up and shutdowns in practice of the *** order to avoid this weakness,the strategy of medium oxygen blast furnace was *** maneuverable zone of the TGR-OBF was determined by the top gas volume,which should not be far from the data of the traditional blast *** deviation of ±12.5% was used,and then the maneuverable blast oxygen content is from 0.30 to 0.47 according to the *** flame temperature and the top gas volume have no much difference compared to those of the traditional blast *** minimum carbon consumption of 357 kg per ton hot metal in the maneuverable zone occurs at the oxygen content of 0.30（fuel saving of 14%）.In the unsteady evolution,the N2 accumulation could approach nearly zero after the recycling reached 6 *** far,some TGR-OBF industrial trials have been carried out in different countries,but the method of medium oxygen enriched TGR-OBF has not been implemented,because the accumulation of N2 was worried *** presented strategy of medium oxygen enriched TGR-OBF is applicable and the strategy with good operational performance is strongly suggested as a forerunner of the full oxygen blast furnace.

关键词： Oxygen blast furnace Top gas recycling Top gas volume Carbon consumption Operation Emission Optimization

Temperature-triggered phase transition in pyridazine hexafluorophosphate

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Chinese Chemical Letters 2015年第1期26卷 145-148页

作者： Dong-Yan Wang Li-Li Qin xue-Li Hou heng-Yun Ye Ordered Matter Science Research Center Southeast University

The pyndazine hexafluorophosphate[C4H5N2]~＋[PF6]^-（1） undergoes a reversible phase transition around140 K,which was confirmed by the DSC measurement.Variable-temperature crystal structures determined at 293 K and 93 K show that the compound crystallizes in the same space group P21/c,indicating that 1 undergoes an iso-structural phase *** the temperature decreases,dielectric measurement of the title compound shows no significant change around the phase transition *** hydrogen bonds are found between molecules at 293 K and 93 l〈 with similar packing *** most distinct difference between the low temperature and room temperature structures is the order-disorder transition of the hexafluorophosphate anion,which is probably the driving force of the phase transition.

关键词： Phase transition Dielectric DSC Crystal structure

Dopamine in the prefrontal cortex plays multiple roles in the executive function of patients with Parkinson's disease

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Neural Regeneration Research 2024年第8期19卷 1759-1767页

作者： Zihang Zhou Yalong Yan heng Gu Ruiao Sun Zihan Liao Ke xue Chuanxi Tang Department of Neurobiology Xuzhou Key Laboratory of NeurobiologyXuzhou Medical UniversityXuzhouJiangsu ProvinceChina

Parkinson’s disease can affect not only motor functions but also cognitive abilities,leading to cognitive *** common issue in Parkinson’s disease with cognitive dysfunction is the difficulty in executive *** functions help us plan,organize,and control our actions based on our *** brain area responsible for executive functions is called the prefrontal co *** acts as the command center for the brain,especially when it comes to regulating executive *** role of the prefrontal cortex in cognitive processes is influenced by a chemical messenger called ***,little is known about how dopamine affects the cognitive functions of patients with Parkinson’s *** this article,the authors review the latest research on this *** start by looking at how the dopaminergic syste m,is alte red in Parkinson’s disease with executive ***,they explore how these changes in dopamine impact the synaptic structure,electrical activity,and connection components of the prefrontal *** authors also summarize the relationship between Parkinson’s disease and dopamine-related cognitive *** information may offer valuable insights and directions for further research and improvement in the clinical treatment of cognitive impairment in Parkinson’s disease.

关键词： dopamine dopamine receptor dopamine transporter executive dysfunction neural network neural oscillation prefrontal cortex synaptic plasticity

Using waste to treat waste:Red mud induced hierarchical porousγ-AlOOH andγ-Al_(2)O_(3) microspheres as superior Pd support for catalytic reduction of 4-nitrophenol

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Particuology 2023年第2期73卷 59-67页

作者： Yuyu Zheng Jingyi Wang Panpan Sun Huimin xue Liyun Zhang Jinxiu Chen heng Zhang Wancheng Zhu Department of Chemical Engineering Qufu Normal UniversityShandong273165China

Toward the imperative treatment of the industrial wastewater containing 4-nitrophenol(4-NP)and industrial solid waste red mud(RM),an innovative approach of“Using waste to treat waste”is *** element Al is leached from the RM first,the resultant NaAlO_(2) solution is hydrothermally converted toγ-AlOOH hierarchical porous microspheres(RMγ-AlOOH HPMSs,average diameter:2.0μm,SBET:77.81 m^(2) g^(-1),pore volume:0.38 cm^(3) g^(-1))in the presence of *** subsequent mild thermal conversion results inγ-Al_(2)O_(3) hierarchical porous microspheres(RMγ-Al_(2)O_(3) HPMSs).Both of the RMγ-AlOOH and RMγ-Al_(2)O_(3) HPMSs are employed as the Pd catalyst support for the catalytic reduction of ***,the as-obtained composite Pd/RMγ-AlOOH and Pd/RMγ-Al_(2)O_(3) exhibit excellent catalytic activities with superior knor as 8204.5 and 4831.4 s^(-1) g^(-1),respectively,significantly higher than that of most Pd based ***,the excellent catalytic stability and durability of the Pd/RMγ-AlOOH and Pd/RMγ-Al_(2)O_(3) within 10 successive cycles of reduction enable the present industrial solid waste RM inducedγ-AlOOH andγ-Al_(2)O_(3) HPMSs as great promising Pd catalyst support for the reduction of the industrial wastewater containing 4-NP.

关键词： Red mud Waste treatment Hierarchical porous AlOOH Al_(2)O_(3) 4-Nitrophenol

Softening and Melting Behavior of Mixed Burden for Oxygen Blast Furnace

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Journal of Iron and Steel Research International 2013年第5期20卷 11-16页

作者： AN Xiu-wei WANG Jing-song LAN Rong-zong HAN Yi-hua xue Qing-guo State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The behaviors of mixed burden in the cohesive zone of oxygen blast furnace were studied by softening and melting tests, and the influence of reducing gas and burden basicity on the softening and melting behaviors of mixed burden was also investigated. The results indicated that the softening range became wide, however, the melting range narrowed sharply in the atmosphere of oxygen blast furnace. The permeability of burden in the oxygen blast furnace was obviously improved comparing with the conventional blast furnace. In addition, the content of sulphur in the dripping iron of oxygen blast furnace was much lower than that of conventional blast furnace, however, the content of carbon increased. An optimum basicity of burden, which could lead to the appearance of the narrower melting range and better permeability of burden, was obtained in the atmosphere of oxygen blast furnace.

关键词： oxygen blast furnace softening melting mixed burden basicity reduction degree

Layperson’s performance on an unconversant type of AED device:A prospective crossover simulation experimental study

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World Journal of Emergency Medicine 2022年第2期13卷 98-105页

作者： Chao-yu Lei heng-wei Qin xue-jie Dong Jia-lin You Lin Zhang Shanghai Jiao Tong University School of Medicine Shanghai 200025China Department of Global Health School of Public HealthPeking UniversityBeijing 100191China School of Public Health Shanghai Jiao Tong University School of MedicineShanghai 200025China School of Nursing Shanghai Jiao Tong UniversityShanghai 200025China

BACKGROUND:Diverse models of automated external defibrillators(AEDs)possess distinctive *** study aimed to investigate whether laypersons trained with one type of AED could intelligently use another initial contact type of AED with varying ***:This was a prospective crossover simulation experimental study conducted among college *** were randomly trained with either AED1(AED1 group)or AED2(AED2 group),and the AED operation performance was evaluated individually(Phase I test).At the 6-month follow-up AED performance test(Phase II test),half of the subjects were randomly switched to use another type of AED,which formed two switches(Switch A:AED1-1 group ***2-1 group;Switch B:AED2-2 group ***1-2 group).RESULTS:A total of 224 college students participated in the *** the phase I test,a significantly higher proportion of successful defibrillation and shorter shock delivery time to achieve successful defibrillation was observed in the AED2 group than in the AED1 *** the phase II test,no statistical differences were observed in the proportion of successful defibrillation in Switch A(51.4%vs.36.6%,P=0.19)and Switch B(78.0%vs.53.7%,P=0.08).The median shock delivery time within participants achieving successful defibrillation was significantly longer in the switched group than that of the initial group in both Switch A(89[81-107]s vs.124[95-135]s,P=0.006)and Switch B(68[61.5-81.5]s vs.95.5[55-131]s,P<0.001).CONCLUSION:College students were able to effectively use AEDs different from those used in the initial training after six months,although the time to shock delivery was prolonged.

关键词： Automated external defibrillator Layperson Cardiac arrest Simulation