检索结果-南通市图书馆

Synthesis and characterization of Li_4Ti_5O_(12) via a hydrolysis process from TiCl_4 aqueous solution

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2014年第4期33卷 459-465页

作者： Xuan-Yu Wang Yun-jiao Li Cang Xu Long Kong lin Li School of Metallurgical Science and Engineering Central South University

Spinel-type lithium and titanium composite oxide Li4TisO12 was successfully synthesized via a novel hydrolysis method followed by calcination using titanium tetrachloride （TIC14） and lithium hydroxide （LiOH.H2O） as raw materials. Three major factors, including LiOH con- centration, LiOH dosage, and hydrolysis temperature were studied for optimizing the synthetic conditions to obtain a phase-pure Li4Ti5012. The physical and electrochemical properties of samples were characterized by X-ray dif- fraction （XRD）, thermogravimetric analysis （TGA）, fourier transform infrared spectroscopy （FT-IR）, scanning electron microscopy （SEM）, and constant current discharge-charge test. The FT-IR results indicate the presence of [TiO6] octahedra. The SEM images show that the Li4Ti5O12 pre- cursor obtained is an amorphous solid with an irregular and rough morphology. It is revealed that the phase-pure spinel Li4Ti5O12 powders with well crystallization and regular morphology can be obtained by calcining the precursor at 800 ℃ for 6 h. The constant current discharge-charge tests indicate that the Li4TisO12 material delivers an excellent cycling ability, maintaining 93.8 % of its initial specific capacity after 60 cycles at a current density of 0.5C.

关键词： Lithium ion battery Titanium tetrachloride Li4Ti5O12 Synthesis Hydrolysis method

J-comb: An image fusion algorithm to combine observations covering different spatial frequency ranges

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2022年第9期65卷 138-156页

作者： Sihan jiao Yuxin lin Xiangyu Shui Jingwen Wu Zhiyuan Ren Di Li National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Centre for Astrochemical Studies Max-Planck-Institut f¨ur Extraterrestrische PhysikGarching 85748Germany Astrophysics Department Munich UniversityMunich 81679Germany NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa

Ground-based, high-resolution bolometric(sub)millimeter continuum mapping observations on spatially extended target sources are often subject to significant missing fluxes. This hampers accurate quantitative analyses. Missing flux can be recovered by fusing high-resolution images with observations that preserve extended structures. However, the commonly adopted image fusion approaches do not maintain the simplicity of the beam response function and do not try to elaborate the details of the yielded beam response functions. These make the comparison of the observations at multiple wavelengths not straightforward. We present a new algorithm, J-comb, which combines the high and low-resolution images linearly. By applying a taper function to the low-pass filtered image and combining it with a high-pass filtered image using proper weights, the beam response functions of our combined images are guaranteed to have near-Gaussian shapes. This makes it easy to convolve the observations at multiple wavelengths to share the same beam response functions. Moreover, we introduce a strategy to tackle the specific problem that the imaging at 850 μm from the present-date ground-based bolometric instrument and that taken with the Planck satellite do not overlap in the Fourier domain. We benchmarked our method against two other widely-used image combination algorithms, CASA-feather and MIRIAD-immerge, with mock observations of star-forming molecular clouds. We demonstrate that the performance of the J-comb algorithm is superior to those of the other two algorithms. We applied the J-comb algorithm to real observational data of the Orion A star-forming region. We successfully produced dust temperature and column density maps with ~10′′angular resolution, unveiling much greater details than the previous results. A py Thon code release of J-comb and implementation of the algorithm are available at https://***/Sihan jiao/J-comb.

关键词： star formation molecular clouds image processing

同方期刊数据库

Analysis of the dynamic performance of an electro-hydrostatic actuator and improvement methods

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2018年第12期31卷 2312-2320页

作者： Zhihui LI Yaoxing SHANG Zongxia jiao Yan lin Shuai WU Xiaobin LI School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing 100083China

As a kind of actuation mechanism for power-by-wire(PBW) actuation systems of more/all electrical aircraft, an electro-hydrostatic actuator(EHA) is a highly integrated local hydraulic actuation system. It is a volume control system consisting of a motor, a pump, an actuator, etc.,which has features of high efficiency and reliability. However, the poor dynamic characteristic is one of the main factors restricting its wide application in aircraft. In this paper, the reason for the poor dynamic characteristic of an EHA is revealed from the perspectives of the natural frequency characteristic and the power requirement, respectively. In other words, the insufficiency of the motor output power at a high frequency is the main factor causing the poor dynamic characteristic of the system, and methods which include increasing the maximum output torque of the motor, reducing the rotational inertia of the motor-pump group, and adopting a double-motorpump group configuration are proposed in this paper, by which the dynamic characteristic of the system can be improved. The feasibility of those methods are verified by simulations. Finally, the dynamic characteristic is tested on an EHA prototype, and results show that saturation of the output torque of the motor is the main factor restricting the dynamic characteristic of the EHA system.

关键词： Dynamic characteristic Motor-pump group Power requirement Rotational inertia

Precipitation Behavior of Cu-1.9Be-0.3Ni-0.15Co Alloy During Aging

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 307-315页

作者： Yan-Chuan Tang Yong-lin Kang Li-Juan Yue Xiao-Liang jiao School of Materials Science and Engineering University of Science and Technology Beijing CNMC Ningxia Orient Group Co. Ltd.

In this paper,the evolutions of microstructure and mechanical properties of Cu-l.9Be-0.3Ni-0.15Co alloy were *** alloys in the condition of the solution treated（soft state） and 37% cold rolled（hard state） were aged at 320 ℃for different time,*** mechanical properties,electrical conductivity and microstructure of the alloy aged for different time were ***,the precipitation kinetics of Cu-1.9Be-0.3Ni-0.15Co alloys was investigated.X-ray diffraction and transmission electron microscopy results reveal that both continuous precipitation and discontinuous precipitation existed in the hard-state Cu-l.9Be-0.3Ni-0.15Co alloy during the whole aging process;the sequence of continuous precipitation is *** →γ″→γ′→γ.Furthermore,the precipitation transformation mechanism of softstate alloy is homogeneous nucleation,while hard-state alloy shows the heterogeneous nucleation（interface nucleation）with the nucleation rate of both states decaying rapidly to zero during aging at 320 ℃.

关键词： Cu-1.9Be-0.3Ni-0.15Co alloy Aging Microstructure Mechanical property Electrical property Precipitation kinetics

An efficient synthesis of 2-(guaiazulen-1-yl)furan derivatives via intramolecular Wittig reactions

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2013年第7期24卷 622-624页

作者： Dao-lin Wang Zhe Dong jiao Xu Di Li College of Chemistry and Chemical Engineering Liaoning Key Laboratory of Synthesis and Application of Functional CompoundBohai University Cosmetology Department Jiamusi InstituteHeilongjiang University of Chinese Medicine

An efficient and mild synthesis of 2-（guaiazulen-l-yl）furans, starting from easily accessible 1-（3-aryl-2- cyanopropenoyl）guaiazulenes, tributylphosphine and acyl chlorides, is described. The strategy employs the intramolecular Wittig protocol as a key step to append the crucial furan ring, leading to the highly functional furans in good yields.

关键词： Guaiazulene Furan lntramolecular Wittig reaction

Dietary L-citrulline supplementation modulates nitric oxide synthesis and antioxidant status of laying hens during summer season

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2021年第2期12卷 661-676页

作者： Victoria A.Uyanga Hongchao jiao Jingpeng Zhao Xiaojuan Wang Hai lin Department of Animal Science College of Animal Science and Veterinary MedicineShandong Provincial Key Laboratory of Animal Biotechnology and Disease ControlShandong Agricultural UniversityNo.61 Daizong StreetTai'an 271018ShandongChina

Background:L-citrulline(L-Cit),a non-protein amino acid,has been implicated in several physiological functions including anti-inflammatory,anti-oxidative,and hypothermic roles,however,there is a paucity of information with regards to its potential in poultry ***:This study was designed to investigate the effects of dietary L-Cit supplementation on the production performance,nitric oxide production,and antioxidant status of laying hens during summer ***-line Brown laying hens(n=288,34 weeks old)were allotted to four treatment,6 replicates of 12 chickens *** treatments of control(basal diets),0.25%,0.50%and 1.00%L-Cit supplementation were fed to chickens for eight(8)*** performance,free amino acid profiles,nitric oxide production,and antioxidant properties were *** samples were collected at the 4th and 8th weeks of the ***:Air temperature monitoring indicated an average daily minimum and maximum temperatures of 25.02°C and 31.01°C *** supplementation with L-Cit did not influence(P>0.05)the production performance,and rectal temperature of laying *** shape index was increased(Pline,ornithine,tryptophan,histidine,GABA,and cystathionine were elevated,but taurine declined with L-Cit *** nitric oxide(NOx)concentration was highest at 1%***,nitric oxide synthase(NOS)activity for total NOS(tNOS)and inducible NOS(iNOS)were upregulated with increasing L-Cit levels,although,tNOS was not affected at the 4th ***-oxidant enzymes including catalase and superoxide dismutase(SOD)were increased with L-Cit supplementation,however,SOD activity was unchanged at 4th week,while total anti-oxidant capacity increased at the 8th week.L-Cit supplementation attenuated the extent of lipid peroxidation,and also inhibited glutathione peroxidase ***:Dietary L-Cit supplementation modulated systemi

关键词： Arginine Antioxidants Laying hens L-citrulline Nitric oxide Summer

Efficacy and safety of Huaiqihuang granule as adjuvant treatment for primary nephrotic syndrome in children: a meta-analysis and systematic review

在线全文

学校读者我要写书评

暂无评论

World Journal of Pediatrics 2021年第3期17卷 242-252页

作者： jiao lin Li-Min Huang Jing-Jing Wang Jian-Hua Mao Department of Nephrology National Clinical Research Center For Child HealthChildren’s HospitalZhejiang University School of MedicineHangzhou 310003China

Background Huaiqihuang(HQH)granule is a traditional Chinese herbal complex that has been used as an adjuvant treatment in clinics for the primary nephrotic syndrome(PNS)for many ***,the effectiveness and safety of HQH have not been systematically *** review aimed to evaluate the effectiveness and safety of HQH in paediatric patients with *** The following databases were searched from inception to Mar 2019:MEDlinE,Cochrane Library,EMBASE,CNKI,Wanfang Database,the Chinese Scientific Journal Database and the Chinese biomedical literature service *** the randomized controlled trials(RCTs)eligible for inclusion were *** primary outcomes were relapse,infection,remission and adverse *** secondary outcomes included serum immunoglobulin levels(IgA,IgG or IgM),T-lymphocyte subtype(CD3+,CD4+,CD8+,CD4+/CD8+),IL-10,TNF-α,TNF-γ,total cholesterol and time of proteinuria turning *** Fourteen RCTs(885 patients)were *** with HQH reduced the chance of relapse[relative risk(RR):0.47;95%CI:0.34,0.66;P<0.001]and infections(RR:0.47;95%Cl:0.35,0.62;P<0.001).No significant difference was found in adverse *** also increased the serum levels of IgA[weighted mean difference(WMD):0.40;95%Cl:0.20,0.60;P<0.001]and IgG(WMD:1.58;95%Cl:1.38-1.78;P<0.001),as well as CD4+[standard mean difference(SMD):0.90;95%Cl:0.12-1.68;P=0.02],CD3+(WMD:4.04;95% CI:3.27-4.82;P<0.001),and the CD4^(+)/CD8^(+)ratio(WMD:0.31;95% CI:0.21-0.41;P<0.001),but decreased the level of CD8+cells(WMD:-3.39;95% CI:-5.73-1.05;P=0.004).No statistically significant difference was found in IgM(WMD:0.05;95% CI:-0.13,0.24;P=0.57).Conclusions HQH could reduce the rate of relapse and the frequency of infection in children with *** apparent adverse effects were ***,the beneficial influence of HQH may act through *** multi-center,large-sample,high-quality studies are needed to confirm the effectiveness and safety of

关键词： Children Huaiqihuang Nephrotic syndrome Meta-analysis

Impact of“ultra low emission”technology of coal-fired power on PM_(2.5)pollution in the Jing-Jin-Ji Region

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

Frontiers in Energy 2021年第1期15卷 235-239页

作者： Xiao LIU Zhilin LIU Weidong jiao Xuan LI Jintai lin Anthony KU National Institute of Clean-and-Low-Carbon Energy Beijing 102211China Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing 100031China NICEA merica Research 2091 Stierlin CtMountain ViewCA 94043USA

In response to severe haze pollution,the Chinese government has announced a series of policies focusing on controlling emissions from coal consumption.“Ultra-low emission”(ULE)technologies have the potential to dramatically reduce emissions from coalfired power plants,and have been deployed at some facilities in recent *** paper estimated the potential environmental benefits of the widespread adoption of ULE in the Jing-Jin-Ji *** modeling scenarios were analyzed for three cases:a“standard”scenario assuming no ULE deployment,a“best case”scenario assuming complete adoption of ULE across all power plants in the region,and a“natural gas”scenario,assuming emissions factors consistent with natural gas-fired power *** simulations show that the widespread adoption of ULE technologies can be an effective and economically competitive option for reducing the impacts of coal-fired power generation on air quality.

关键词： air quality atmospheric model coal Jing-Jin-Ji Region PM_(2.5) ultra-low emissions

Modeling and Analyzing Dynamic Response for An Offshore Bottom-Fixed Wind Turbine with Individual Pitch Control

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2022年第3期36卷 372-383页

作者： XIE Shuang-yi ZHANG Kai-fei HE jiao GAO Jian ZHANG Cheng-lin College of Mechanical Engineering Chongqing University of TechnologyChongqing 400044China School of Mechanical and Power Engineering Chongqing University of Science&TechnologyChongqing 401331China Beijing Institute of Precision Mechatronics and Controls Beijing 100076China Fishery Machinery and Instrument Research Institute Chinese Academy of Fishery SciencesShanghai 200092China College of Engineering Science and Technology Shanghai Ocean UniversityShanghai 201306China

The asymmetric or periodically varying blade loads resulted by wind shear become more significant as the blade length is increased to capture more wind ***,compared with the onshore wind turbines,their offshore counterparts are subjected to additional wave loadings in addition to wind loadings within their ***,vibration control and fatigue load mitigation are crucial for safe operation of large-scale offshore wind *** view of this,a multi-body model of an offshore bottom-fixed wind turbine including a detailed drivetrain is established in this ***,an individual pitch controller(IPC)is designed using disturbance accommodating *** feedback is used to add damping in flexible modes of concern,and a state estimator is designed to predict unmeasured ***,a coupled aero-hydro-servo-elastic model is *** on this coupled model,the load reduction effect of IPC and the dynamic responses of the drivetrain are *** results showed that the designed IPC can effectively reduce the structural loads of the wind turbine while stabilizing the turbine power ***,it is found that the drivetrain dynamic responses are improved under IPC.

关键词： wind turbine individual pitch controller disturbance accommodating control multi-body modeling drivetrain