检索结果-南通市图书馆

Growth and Magnetic Properties of Sol-Gel Derived Co-Doped ZnO Thin Film

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2006年第Z1期24卷 59-63页

作者： Young sung kim Ki chul kim Won Pil Tae Dae Ho Yoon Tae Seok Park Su Jeong Suh Advanced Material Process of Information Technology Sungkyunkwan University Suwon 440-746 Korea Cambridge-ETRI Joint R&D Centre Electronics and Telecommunications Research Institute Daejeon 305-350 Korea Ulsan Industry Promotion Techno Park Ulsan 683-804 Korea Advanced Material Process of Information Technology Sungkyunkwan University Suwon 440-746 Korea Advanced Material Process of Information Technology Sungkyunkwan University Suwon 440-746 Korea Advanced Material Process of Information Technology Sungkyunkwan University Suwon 440-746 Korea

Zn1-xCoxO films were grown on glass by sol-gel spin coating process. A homogeneous and stable Zn1-xCoxO sol was prepared by dissolving zinc acetate dihydrate, cobalt acetate tetrahydrate and aluminium chloride hexahydrate as solutes in solution of isopropanol and monoethanolamine. The films were postheated and vacuum annealed, and investigated for c-axis preferred orientation and electromagnetic properties. Zn1-xCoxO films with different Co concentrations were oriented well along the c-axis, especially the Zn1-xCoxO film with 10% Co(atom fraction) was highly c-axis oriented. The transmittance spectra show that Zn1-xCoxO films occur d-d transition and sp-d exchange interaction between Co2+ ions. The electrical resistivity of the films at 10% Co had the lowest value because the crystallite size became largest and the crystallinity of the c-axis was improved. X-ray photoelectron spectroscopy and alternating gradient magnetometer analyses indicated that no Co metal cluster was formed, and the ferromagnetism at room temperature appeared. The characteristics of the electrical resistivity and room temperature ferromagnetism of sol-gel derived Zn1-xCoxO films suggest a potential application of dilute magnetic semiconductor devices.

关键词： sol-gel Zn1-xCoxO thin film dilute magnetic semiconductor (DMS)

Effects of Cr doping on structural and electrochemical properties of Li_(4)Ti_(5)O_(12) nanostructure for sodium-ion battery anode

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第8期30卷 465-472,I0010页

作者： Sang Hyuk Gong Ji Hyeon Lee Dong Won Chun Jee-Hwan Bae sung-chul kim Seungho Yu Sahn Nahm Hyung-Seok kim Center for Energy Storage Research Korea Institute of Science and Technology5Hwarang-ro 14-gilSeongbuk-gu02792 SeoulRepublic of Korea Department of Materials Science and Engineering Korea University145Anam-roSeongbuk-gu02841 SeoulRepublic of Korea Department of Chemical and Biological Engineering Korea University145Anam-roSeongbuk-gu02841 SeoulRepublic of Korea Advanced Analysis Center Korea Institute of Science and Technology5Hwarang-ro 14-gilSeongbuk-gu02792 SeoulRepublic of Korea

Sodium-ion batteries are considered as promising alternatives to lithium-ion batteries,owing to their low cost and abundant raw *** the several candidate materials for the anode,spinel-type Li_(4)Ti_(5)O_(12)has potential owing to its superior safety originating from an appropriate operating voltage and the reversible Na^(+)intercalation ***,a low diffusion coefficient for Na^(+)and the insulating nature of LTO remains challenging for practical sodium-ion battery ***,we present a strategy for integrating physical and chemical approaches to achieve superior electrochemical properties in *** demonstrate that carefully controlling the amount of Cr doping is crucial to enhance the electrochemical properties of nanostructured *** Cr doped LTO shows a superior reversible capacity of 110 m Ah g^(-1) after 400 cycles at 1 C,with a three-fold higher capacity(75 m Ah g^(-1))at 10 C compared with undoped LTO *** suggests that appropriately Cr doped nanostructured LTO is a promising anode material for sodium-ion batteries.

关键词： Sodium-ion batteries Spinel type Li_(4)Ti_(5)O_(12) Anode materials Nanostructuring Cr-doping

Ionizing terahertz waves with 260 MV/cm from scalable optical rectification

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第6期13卷 1075-1087页

作者： Hyeongmun kim chul Kang Dogeun Jang Yulan Roh Sang Hwa Lee Joong Wook Lee Jae Hee sung Seong Ku Lee Ki-Yong kim Advanced Photonics Research Institute GISTGwangju61005Korea Department of Physics and Optoelectronics Convergence Research Center Chonnam National UniversityGwangju61186Korea Pohang Accelerator Laboratory POSTECHPohang37673Korea Center for Relativistic Laser Science Institute for Basic ScienceGwangju61005Korea Institute for Research in Electronics and Applied Physics Department of PhysicsUniversity of MarylandCollege ParkMaryland20742USA

Terahertz(THz)waves,known as non-ionizing radiation owing to their low photon energies,can actually ionize atoms and molecules when a sufficiently large number of THz photons are concentrated in time and ***,we demonstrate the generation of ionizing,multicycle,15-THz waves emitted from large-area lithium niobate crystals via phase-matched optical rectification of 150-terawatt laser pulses.A complete characterization of the generated THz waves in energy,pulse duration,and focal spot size shows that the field strength can reach up to 260 megavolts per *** particular,a single-shot THz interferometer is employed to measure the THz pulse duration and spectrum with complementary numerical *** intense THz pulses are irradiated onto various solid targets to demonstrate THz-induced tunneling ionization and plasma *** study also discusses the potential of nonperturbative THz-driven ionization in gases,which will open up new opportunities,including nonlinear and relativistic THz physics in plasma.

关键词： optical interferometer matched

Nanocrystalline low-silica X zeolite as an efficient ion-exchanger enabling fast radioactive strontium capture

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 of Chemical Science and Engineering 2024年第9期18卷 15-23页

作者： Hyungmin Jeon Susung Lee Jeong-chul kim Minkee Choi Department of Chemical and Biomolecular Engineering(BK21 Four) Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea Center for Nanomaterials and Chemical Reactions Institute for Basic Science(IBS)Daejeon 34141Republic of Korea

NaA zeolite(Si/Al=1.00)has been commercially applied for capturing radioactive 90Sr^(2+)because of its high surface charge density,effectively stabilizing the multivalent ***,owing to its narrow micropore opening(4.0Å),large micron-sized crystallites,and bulkiness of hydrated Sr^(2+),the Sr^(2+)exchange over NaA has been limited by very slow *** this study,we synthesized nanocrystalline low-silica X by minimizing a water content in a synthesis gel and utilizing a methyl cellulose hydrogel as a crystal growth *** resulting zeolite exhibited high crystallinity and Al-rich framework(Si/Al of approximately 1.00)with the sole presence of tetrahedral Al sites,which are capable of high Sr^(2+)uptake and ion ***,the zeolite with a FAU topology has a much larger micropore opening size(7.4Å)and a much smaller crystallite size(~340 nm)than NaA,which enable significantly enhanced ion-exchange *** to conventional NaA,the nanocrystalline low-silica X exhibited remarkably increased Sr^(2+)-exchange kinetics(>18-fold larger rate constant)in batch *** both the nanocrystalline low-silica X and NaA exhibited comparable Sr^(2+)capacities under equilibrated conditions,the former demonstrated a 5.5-fold larger breakthrough volume than NaA under dynamic conditions,attributed to its significantly faster Sr^(2+)-exchange kinetics.

关键词： Sr^(2+)removal low-silica X zeolite nanocrystal hydrogel methyl cellulose

The effect of proton irradiation on magnetic properties of NiCuZn ferrite

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The effect of proton irradiation on magnetic properties of N...

Development and application of a multi-step porcine in vitro system to evaluate feedstuffs and feed additives for their efficacy in nutrient digestion, digesta characteristics, and intestinal immune responses

8th International Symposium on the Industrial Applications of the Mossbauer Effect

作者： sung Wook Hyun Seungkyu Han Sam Jin kim chul sung kim Department of Physics Kookmin UniversitySeoul 136-702Korea

Here,we report the experimental studies on the effect of 5.0 MeV proton irradiation on the magnetic properties of NiCuZnFeO based on the x-ray diffraction,magnetization,and Mossbauer spectroscopy. NiCuZnFeO powder was prepared by the solid-state reaction method and annealed at 900°*** prepared samples were proton-irradiated with 10,and 20 pC/*** crystal structure was found to be cubic

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Animal Nutrition 2024年第2期17卷 265-282页

作者： Hee Yeon kim Jun-Ok Moon sung Woo kim Application Center CJ Blossom Park Department of Animal Science North Carolina State University

In vitro model provides alternatives to the use of live animals in research. In pig nutrition, there has been a tremendous increase in in vivo research over the decades. Proper utilization of in vitro models could provide a screening tool to reduce the needs of in vivo studies, research duration, cost, and the use of animals and feeds. This study aimed to develop a multi-step porcine in vitro system to simulate nutrient digestion and intestinal epithelial immune responses affected by feedstuffs and feed additives. Seven feedstuffs(corn, corn distillers dried grains with solubles [corn DDGS], barley, wheat, soybean meal, soy protein concentrates, and Corynebacterium glutamicum cell mass [CGCM]), feed enzymes(xylanase and phytase), and supplemental amino acids(arginine, methionine, and tryptophan), were used in this in vitro evaluation for their efficacy on digestibility, digesta characteristics, and intestinal health compared with the results from previously published in vivo studies. All in vitro evaluations were triplicated. Data were analyzed using Mixed procedure of SAS9.4. Evaluations included(1) nutrient digestibility of feedstuffs,(2) the effects of feed enzymes, xylanase and phytase, on digestibility of feedstuffs and specific substrates, and(3) the effects of amino acids, arginine, tryptophan, and methionine, on anti-inflammatory, anti-oxidative, and anti-heat stress statuses showing their effects(P < 0.05) on the measured items. Differences in dry matter and crude protein digestibility among the feedstuffs as well as effects of xylanase and phytase were detected(P < 0.05), including xylo-oligosaccharide profiles and phosphorus release from phytate. Supplementation of arginine, tryptophan, and methionine modulated(P < 0.05) cellular inflammatory and oxidative stress responses. The use of this in vitro model allowed the use of 3 experimental replications providing sufficient statistical power at P < 0.05. This indicates in vitro models can have increased prec

关键词： Digestion Feed additive Feedstuff In vitro Intestine Pig

Lipid phosphorylation by a diacylglycerol kinase suppresses ABA biosynthesis to regulate plant stress responses

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2024年第2期17卷 342-358页

作者： Jianwu Li Shuaibing Yao Sang-chul kim Xuemin Wang Department of Biology University of Missouri-St.LouisSt.LouisMO 63121USA Donald Danforth Plant Science Center St.LouisMO 63132USA

Lipid phosphorylation by diacylglycerol kinase(DGK)that produces phosphatidic acid(PA)plays important roles in various biological processes,including stress responses,but the underlying mechanisms remain ***,we show that DGK5 and its lipid product PA suppress ABA biosynthesis by interacting withABA-DEFICIENT2(ABA2),a key ABA biosynthesis enzyme,to negatively modulate plant responseto abiotic stress tested in Arabidopsis *** of DGK5 function rendered plants less damaged,whereas overexpression(OE)of DGK5 enhanced plant damage to water and salt *** dgk5 mutant plants exhibited decreased total cellular and nuclear levels of PA with increased levels of diacylglycerol,whereas DGK5-OE plants displayed the opposite ***,we found that both DGK5 and PA bind to the ABA-synthesizing enzyme ABA2 and suppress its enzymatic ***,the dgk5 mutant plants exhibited increased levels of ABA,while DGK5-OE plants showed reduced ABA *** addition,we showed that both DGK5 and ABA2 are detected in and outside the nuclei,and loss of DGK5 function decreased the nuclear association of *** found that both DGK5 activity and PA promote nuclear association of *** together,these results indicate that both DGK5 and PA interact with ABA2 to inhibit its enzymatic activity and promote its nuclear sequestration,thereby sup-pressing ABA production in response to abiotic *** study reveals a sophisticated mechanism by which DGK5 and PA regulate plant stress responses.

关键词： diacylglycerol kinase phosphatidic acid diacylglycerol lipid signaling stress responses lipid-protein binding protein-protein interaction Arabidopsis

Opportunities and challenges in cathode development for non-lithium-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

eScience 2024年第4期4卷 1-6页

作者： Haegyeom kim Jae chul kim Materials Sciences Division Lawrence Berkeley National Laboratory94720CAUSA Department of Chemical Engineering and Materials Science Stevens Institute of Technology07030NJUSA

Lithium(Li)-ion batteries have stimulated the societal transformation to clean energy *** carry-on electricity is revolutionizing how society communicates,functions,and evolves efficiently by enabling mobile electronics,zero-emission electric vehicles,and stationary energy *** preparation for the sustainable energy future,however,there are growing concerns about depleting critical elements used in the Li technology(e.g.,lithium,cobalt,and nickel),especially for large-scale applications that will accelerate the rate of elemental *** non-Li-based rechargeable batteries composed of earth-abundant elements,such as sodium,potassium,magnesium,and calcium,have been proposed and explored as alternative systems to promote sustainable development of energy *** this perspective,we discuss challenges in Li-ion batteries in the sustainability aspect and provide our opinions on the potential applications of non-Li-based *** also highlight the current status,important progress,and remaining challenges of the Li-alternative technologies.

关键词： Batteries Sodium Potassium Lithium Multi-valent Energy storage

Soleus arthrogenic muscle inhibition following acute lateral ankle sprain correlates with symptoms and ankle disability but not with postural control

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第4期13卷 559-568,F0003页

作者： Kyung-Min kim Joo-sung kim Alan R.Needle Department of Sport Science Sungkyunkwan UniversitySuwon-si 16419Republic of Korea Department of Health and Human Performance Texas State UniversitySan MarcosTX 78666USA Department of Public Health&Exercise Science Appalachian State UniversityBooneNC 28608USA Department of Rehabilitation Science Appalachian State UniversityBooneNC 28608USA

Background:Acute lateral ankle sprains(ALAS)are associated with long-term impairments and instability tied to altered neural *** muscle inhibition(AMI)has been observed in this population;however,relationships with injury-related impairments are unclear,potentially due to the resting,prone position in which AMI is typically *** AMI during bipedal stance may provide a better understanding of this ***:AMI was assessed in 38 young adults(19 ALAS within 72 h of injury:10 males,21.4±2.7 years;19 healthy controls:10 males,21.9±2.2 years;mean±SD)using the Hoffmann reflex(H-reflex)during bipedal *** stimulation was administered to identify the _(max)imal H-reflex(H_(max))and _(max)imal motor response(M_(max))from the soleus,fibularis longus,and tibialis anterior *** primary outcome measure was the H_(max)/M_(max) *** outcomes included acute symptoms(pain and swelling),postural control during bipedal stance,and self-reported ***:No significant group-by-limb interactions were observed for any ***,a significant group main effect was observed in the soleus muscle(F(1,35)=6.82,p=0.013),indicating significantly lower H_(max)/M_(max) ratios following ALAS(0.38±0.20)compared to healthy controls(0.53±0.16).Furthermore,lower H_(max)/M_(max) ratios in the soleus significantly correlated with acute symptoms and self-reported function but not with postural ***:This study supports previous evidence of AMI in patients with ALAS,providing insight into neurophysiologic impacts of musculoskeletal *** results suggest that assessing AMI in a standing position following acute injury may provide valuable insight into how AMI develops and guide potential therapeutic options to curb and offset the formation of joint instability.

关键词： Acute injuries Balance Hoffmann reflex Neural excitability Patient-reported outcomes