检索结果-南通市图书馆

Spherical modification of tungsten oxide powder and its mechanism analysis

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2015年第3期34卷 183-188页

作者： cong-cong wang Cheng-Chang Jia Peng Gao Guo-Cheng Gai Yu-Fen Yang School of Materials Science and Engineering University of Science and Technology Beijing Powder Technology R&D Group Department of Material Science and EngineeringTsinghua University

Owing to its high production costs, complexity of equipment, and difficulty in controlling parameters, spherical or subglobose tungsten powder preparation method cannot meet the demand of industrial production. Tungstic oxide powder was treated by particle composite system and its effects were studied. Morphologies of par- ticles were investigated by scanning electron microscopy （SEM）. Particle size analysis was carried out and the related mechanism was discussed. The results show that the processing effect is best when the rotational speed is set at 4,000 ***-1 for 15 rain： the powder particles become nearly spherical and their sharp edge angles are rounded off and reshaped. When the processing time is 60 min, the powders smash to pieces because of too much energy inputting. So the test results, such as grain size distribution, can be explained well. Nearly spherical tungsten powder is obtained after reduction at 780 ℃ for 2 h and its flow ability is significantly improved.

关键词： Nearly spherical tungsten powder Grain size Modification Particle composite system

Spherical modification of tungsten powder by particle composite system

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第6期41卷 1972-1976页

作者： cong-cong wang Cheng-Chang Jia Peng Gao Guo-Sheng Gai Yu-Fen Yang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Powder Technology R&D Group Department of Material Science and EngineeringTsinghua UniversityBeijing 100084China

Owing to contradiction between increasing demand of spherical tungsten powder and limitation of traditional manufacturing technology,a novel preparation method was developed to sphericize the polygonal tungsten powder by means of modification of particle composite *** powder particles were modified by par-ticle composite system,and detailed characterization by scanning electron microscopy(SEM)was *** size distribution and function mechanism were analyzed,and the internal relationship between average diameter and processing time was *** results show that the spherical tungsten powder with an average diameter of 6.41μm is obtained from polyhedral tungsten powder with an average diameter of 7.50μ*** spherical effect could be achieved(sharp edge angles of particles are rounded off and reshaped)when the processing time is over 30 *** relationship between average diameter(d)and pro-cessing time can be described by the exponential decay model,which provides a good interpretation for the process of *** relationship between them can be expressed by the equation d=1.87406exp(-x/8.92718)+*** proposed method could readily enable large-scale production of spherical tungsten powder.

关键词： Tungsten powder Modification Average diameter Powder metallurgy

Dielectric properties of spark plasma sintered AlN/SiC composite ceramics

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 589-594页

作者： Peng Gao Cheng-chang Jia Wen-bin Cao cong-cong wang Dong Liang Guo-liang Xu School of Materials Science and Engineering University of Science and Technology Beijing

In this study, we have investigated how the dielectric loss tangent and permittivity of AlN ceramics are affected by factors such as powder mixing methods, milling time, sintering temperature, and the addition of a second conductive phase. All ceramic samples were pre-pared by spark plasma sintering （SPS） under a pressure of 30 MPa. AlN composite ceramics sintered with 30wt%-40wt%SiC at 1600℃ for 5 min exhibited the best dielectric loss tangent, which is greater than 0.3. In addition to AlN and β-SiC, the samples also contained 2H-SiC and Fe5Si3, as detected by X-ray difraction （XRD）. The relative densities of the sintered ceramics were higher than 93%. Experimental results indicate that nano-SiC has a strong capability of absorbing electromagnetic waves. The dielectric constant and dielectric loss of AlN-SiC ce-ramics with the same content of SiC decreased as the frequency of electromagnetic waves increased from 1 kHz to 1 MHz.

关键词： ceramic materials composite materials aluminum nitride silicon carbide spark plasma sintering dielectric losses

Influence of plasma on the densification mechanism of SPS under multi-field effect

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2014年第9期21卷 906-912页

作者： Yu-hong Chang Di Huang Cheng-chang Jia Zhao-wen Cui cong-cong wang Dong Liang School of Materials Science and Engineering University of Science and Technology Beijing

The densification mechanism of an Fe-based alloy powder containing tiny oxide particles under the synergic multi-field effect of spark plasma sintering （SPS） was investigated. Metallographic microscopy and scanning electron microscopy were used to observe the morphology of samples sintered at different temperatures, and the temperature dislribution in an individual spherical powder particle during sintering was calculated in consideration of the influence of plasma, which was qualified and quantified through the analysis of the U-Icurve. The plasma was observed to play a substantial role in activating and heating the samples at the very early stage of sintering, whereas the joule-heat effect played a dominant role during sintering. Moreover, the plasma also facilitated the diffusion and migration of materials for neck formation.

关键词： iron alloys spark plasma sintering plasma temperature distribution densification diffusion

Solitary necrotic nodules of the liver with"ring"-like calcification:A case report

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2022年第21期10卷 7409-7414页

作者： Jin-Peng Bao Hu Tian Hao-Chen wang cong-cong wang Bo Li Department of General Surgery The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qianfoshan HospitalJinan 250014Shandong ProvinceChina Department of Gastroenterology Shandong First Medical UniversityJinan 250024Shandong ProvinceChina Department of General Surgery Shandong Provincial Qianfoshan HospitalShandong UniversityJinan 250100Shandong ProvinceChina

BACKGROUND Solitary necrotic nodule of the liver(SNNL)is a rare benign lesion with a complete necrotic core and a clear fibrous capsule containing elastic *** present the case of a patient with a radiographic computed tomography(CT)finding of"ring"-like annular calcification within the lesion and postoperative pathologic diagnosis of necrotic nodules wrapped by dense fibers in liver tissue,as well as the patient's subsequent management and *** SUMMARY A 38-year-old Chinese woman with a history of systemic lupus erythematosus treated with prednisone and hydroxychloroquine,without any symptoms,was found to have hepatic space-occupying lesions by imaging examination at a health examination.A subsequent CT scan suggested a space-occupying lesion of the liver with annular calcification,which was not defined to be benign or *** that,a laparoscopic hepatic space-occupying resection was *** postoperative pathological diagnosis was necrotic nodules wrapped by dense fibers in the liver tissue,and the final diagnosis was *** patient had an uneventful postoperative *** There is a"ring"-like calcification in *** patient had a history of systemic lupus erythematosus,without a history of parasite infection,trauma,or ***,whether the etiology and pathological changes of SNNL are related to rheumatic immune diseases remains to be investigated.

关键词： Solitary necrotic nodules of the liver Annular calcification Rheumatic immune disease Laparoscopic hepatic space-occupying resection Case report

Expression of IL-2 and IL-11 and its significance in patients with ankylosing spondylitis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2013年第1期6卷 76-78页

作者： Feng Liu Fan wang cong-cong wang Nuo Li Shu-Feng Li Department of Orthopedics Zhangqiu People's Hospital Department of Orthopedics Qianfoshan Hospital

Objective:To explore the expression of IL-2 and IL-11 and its significance in patients with ankylosing spondylitis(AS).Methods:A total of 48 active AS patients in our hospital and 40 normal control subjects were selected in our *** ankylosing spondylitis disease activity index(BASDAI),Bath ankylosing spondylitis functional index(BASFI),Bath ankylosing spondylitis metrology index(BASMI),ESR and CRP expression levels were compared before treatment,12 h after treatment and 24 h after ***-2 and IL-11 expression were also compared between these two ***:The BASDAI score,BASH score and BASMI score of the AS patients before treatment significantly decreased compared with those 12 weeks and 24 weeks after treatment(P0.05). Pearson’s linear-correlation analysis showed that serum IL-2 level had a positive correlation with BASDAI,BASFI,BASMI,ESR and CRP(r=0.661.0.547,0.474,0.362,0.416,P<0.05) and serum IL-11 level had a negative correlation with BASDAI,BASFI,BASMI,ESR and CRP(r=-0.629, -0.412,-0.422,-0.387,-0.408,-0.315,P<0.05).Conclusions:Serum levels of IL-2 in active AS patients significantly increase and will decrease after ***,serum levels of IL- 11 significantly decrease and will increase after treatment,which indicates that serum IL-2 has a positive correlation with the degree of AS and serum IL-11 has a negative correlation with the degree of AS,both of which are correlated closely with the onset of AS.

关键词： Ankylosing spondylitis IL-2 IL-11

Dielectric properties of AlN/Mo composite ceramics prepared by spark plasma sintering method at different processing conditions

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2022年第4期41卷 1369-1374页

作者： Peng Gao Cheng-Chang Jia Wen-Bin Cao cong-cong wang Guo-Liang Xu Dong Liang Zhao-Wen Cui School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

In this study,the effects of powder mixed method,sintering temperature,and the additive amount of the conductive phase on the dielectric loss tangent and permittivity constant of AlN/Mo composite ceramics were *** the ceramic samples were prepared by spark plasma sintering(SPS).AlN composite ceramics with additional 10 vol%Mo sintered at 1400℃holding for 5 min exhibit the best dielectric loss tangent,which is greater than ***/Mo ceramics with additional 20 vol%Mo become conductive,with the resistivity of 0.05–0.06Ω·***-energy ball milling is better than magnetic stirring powder mixing *** addition,the additive Mo and lower sintering temperature lead to a better property with the increase in the electromagnetic wave frequency range of 1×10^(3)–1×10^(6)Hz.

关键词： Aluminum nitride Molybdenum Dielectric loss Spark plasma sintering

Gamma oscillations and their role in orchestrating balance and communication following stroke

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第2期20卷 477-478页

作者： Montana Samantzis cong wang Matilde Balbi Queensland Brain Institute The University of QueenslandBrisbaneQLDAustralia Engineering Research Centre of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina

Induced brain oscillations in the gamma range have recently garnered attention due to their reported neuroprotective effects in the treatment of Alzheimer’s *** method differs from pharmacological approaches by tapping into the neuronal population dynamics that underlie the homeostatic processes in the brain that are crucial for the recovery of ***,induced gamma-range oscillations have been used to improve cerebral blood flow,motor function,and synaptic plasticity in a mouse model of focal stroke,highlighting the broad potential of recruiting intrinsic recovery processes for the treatment of neurological *** open questions,such as the frequency specificity of the benefits,will shed light on the intrinsic processes involved and allow clinicians to optimize recovery after stroke.

关键词： protective specificity Alzheimer

Future development of Good Agricultural Practice in China under globalization of traditional herbal medicine trade

在线全文

学校读者我要写书评

暂无评论

Chinese Herbal Medicines 2021年第4期13卷 472-479页

作者： Ru Zhang Ming-xu Zhang Yuan Chen cong-cong wang Chun-hong Zhang Heidi Heuberger Huan-ting Li Min-hui Li Baotou Medical College Baotou 014040China Institute of Crop Science and Plant Breeding Bavarian State Research Center for AgricultureFreisingGermany Inner Mongolia Hospital of Traditional Chinese Medicine Hohhot 010020China Inner Mongolia Key Laboratory of Characteristic Geoherbs Resources Protection and Utilization Baotou 014040China Key Laboratory of Resourceology of Chinese Medicinal Materials Baotou 014040China Inner Mongolia Medical University Hohhot 010110China

Traditional herbal medicine(THM)is an important part of the traditional Chinese medicine *** to its high medicinal potential,it should not only serve for the Chinese people’s medical use,but also contribute to the world medicine,THM for the international market must be standardized and large-scale,and produced according to the"Good Agriculture Practice"(GAP).The quality of THM directly affects the patient’s treatment status and safety of ***,the quality assurance of THM runs through the entire process of research and development,production and clinical *** standardized production and cultivation of THM is the starting point of the THM industry chain and plays a decisive role in the economic development of the THM *** article summarizes the development history,limitations and future development of GAP,and clarifies the opportunities for THM in the rapid development of the international and domestic Chinese medicine *** addition,analyzing the deficiencies that were existing in the former GAP implementation process and by suggesting science-based quality measures,it is hoped to stipulate improved GAP guidelines in the future and to lay the foundation for a modern THM international trade.

关键词： Belt and Road Initiatives Good Agricultural and Collection Practices Good Agricultural Practice quality assurance traditional herbal medicine