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Wild Nutrition’s Food-Grown® Magnesium Supplementation Increases Sleep Quality and Sleep Duration and Reduces Stress in a Healthy Adult Population: A Double-Blind, Randomised, Placebo-Controlled Study
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作者 David Briskey Jane Erickson +1 位作者 Chelsie Smith Amanda Rao 《Food and Nutrition Sciences》 CAS 2024年第7期509-523,共15页
Background: Magnesium, an essential mineral crucial for various bodily functions, has been shown to positively influence sleep patterns. This study aimed to evaluate the efficacy of Food-Grown® magnesium in enhan... Background: Magnesium, an essential mineral crucial for various bodily functions, has been shown to positively influence sleep patterns. This study aimed to evaluate the efficacy of Food-Grown® magnesium in enhancing sleep quality and duration, as well as overall well-being. Methods: Eighty participants were randomly assigned to receive either 80 mg of Food-Grown® magnesium or a placebo (microcrystalline cellulose) daily for 8 weeks. Participants completed questionnaires assessing sleep quality, daytime drowsiness, quality of life, anxiety, and stress levels. Additionally, participants maintained daily sleep diaries and wore wrist-worn actigraphy devices. The primary outcome measured was the change in sleep quality and duration. Results: Seventy-one participants fulfilled all study requirements (35 in the active group and 36 in the placebo group). Magnesium supplementation significantly improved reported sleep quality, with the active group showing a 32% increase compared to 16% in the placebo group (p = 0.034). Moreover, magnesium supplementation led to a decrease in reported stress scores at week 8 compared to the placebo group (3.7 ± 2.6 vs. 5.5 ± 3.1, respectively). Both the magnesium and placebo groups exhibited significant increases in reported sleep duration and reductions in time to fall asleep, sleep disturbance, sleep latency, sleep medication usage, and total Pittsburgh Sleep Quality Index score at week 8 compared to baseline. Conclusion: Magnesium supplementation notably enhanced sleep quality and reduced stress levels compared to the placebo group. These findings highlight the potential of magnesium as a beneficial supplement for improving sleep quality and overall well-being. 展开更多
关键词 Magnesium Sleep Quality Sleep Duration STRESS Food-grown
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Electrochemically Grown Ultrathin Platinum Nanosheet Electrodes with Ultralow Loadings for Energy-Saving and Industrial-Level Hydrogen Evolution 被引量:4
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作者 Lei Ding Zhiqiang Xie +8 位作者 Shule Yu Weitian Wang Alexander Y.Terekhov Brian K.Canfield Christopher B.Capuano Alex Keane Kathy Ayers David A.Cullen Feng-Yuan Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期257-274,共18页
Nanostructured catalyst-integrated electrodes with remarkably reduced catalyst loadings,high catalyst utilization and facile fabrication are urgently needed to enable cost-effective,green hydrogen production via proto... Nanostructured catalyst-integrated electrodes with remarkably reduced catalyst loadings,high catalyst utilization and facile fabrication are urgently needed to enable cost-effective,green hydrogen production via proton exchange membrane electrolyzer cells(PEMECs).Herein,benefitting from a thin seeding layer,bottom-up grown ultrathin Pt nanosheets(Pt-NSs)were first deposited on thin Ti substrates for PEMECs via a fast,template-and surfactant-free electrochemical growth process at room temperature,showing highly uniform Pt surface coverage with ultralow loadings and vertically well-aligned nanosheet morphologies.Combined with an anode-only Nafion 117 catalyst-coated membrane(CCM),the Pt-NS electrode with an ultralow loading of 0.015 mgPt cm−2 demonstrates superior cell performance to the commercial CCM(3.0 mgPt cm^(−2)),achieving 99.5%catalyst savings and more than 237-fold higher catalyst utilization.The remarkable performance with high catalyst utilization is mainly due to the vertically well-aligned ultrathin nanosheets with good surface coverage exposing abundant active sites for the electrochemical reaction.Overall,this study not only paves a new way for optimizing the catalyst uniformity and surface coverage with ultralow loadings but also provides new insights into nanostructured electrode design and facile fabrication for highly efficient and low-cost PEMECs and other energy storage/conversion devices. 展开更多
关键词 Seeding layer Electrochemically grown Pt nanosheet Ultralow loadings High catalyst utilization Hydrogen evolution
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Raised bed planting promotes grain number per spike in wheat grown after rice by improving spike differentiation and enhancing photosynthetic capacity
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作者 DU Xiang-bei XI Min +3 位作者 WEI Zhi CHEN Xiao-fei WU Wen-ge KONG Ling-cong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第6期1631-1644,共14页
The yield of wheat in wheat–rice rotation cropping systems in the Yangtze River Plain, China, is adversely impacted by waterlogging. A raised bed planting(RBP) pattern may reduce waterlogging and increase the wheat y... The yield of wheat in wheat–rice rotation cropping systems in the Yangtze River Plain, China, is adversely impacted by waterlogging. A raised bed planting(RBP) pattern may reduce waterlogging and increase the wheat yield after rice cultivation by improving the grain number per spike. However, the physiological basis for grain formation under RBP conditions remains poorly understood. The present study was performed over two growing seasons(2018/2019and 2019/2020) to examine the effects of the planting pattern(i.e., RBP and flat planting(FP)) on the floret and grain formation features and leaf photosynthetic source characteristics of wheat. The results indicated that implementation of the RBP pattern improved the soil–plant nitrogen(N) supply during floret development, which facilitated balanced floret development, resulting in a 9.5% increase in the number of fertile florets per spike. Moreover, the RBP pattern delayed wheat leaf senescence and increased the photosynthetic source capacity by 13.9%, which produced more assimilates for grain filling. Delayed leaf senescence was attributed to the resultant high leaf N content and enhanced antioxidant metabolism. Correspondingly, under RBP conditions, 7.6–8.6% more grains per spike were recorded, and the grain yield was ultimately enhanced by 10.4–12.7%. These results demonstrate that the improvement of the spike differentiation process and the enhancement of the leaf photosynthetic capacity were the main reasons for the increased grain number per spike of wheat under the RBP pattern, and additional improvements in this technique should be achievable through further investigation. 展开更多
关键词 grain number floret development photosynthetic capacity wheat grown after rice
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Microstructure of flow pattern defects in boron-doped Czochralski-grown silicon 被引量:1
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作者 LIU Caichi HAO Qiuyan +5 位作者 ZHANG Jianfeng TENG Xiaoyun Sun Shilong Qigang Zhou WANG Jing XIAO Qinghua 《Rare Metals》 SCIE EI CAS CSCD 2006年第4期389-392,共4页
The morphology and microstructure of flow pattern defects (FPDs) in lightly boron-doped Czochralski-grown silicon (Cz-Si) crystals were investigated using optical microscopy and atomic force microscopy. The experi... The morphology and microstructure of flow pattern defects (FPDs) in lightly boron-doped Czochralski-grown silicon (Cz-Si) crystals were investigated using optical microscopy and atomic force microscopy. The experimental results showed that the morphology of FPDs was parabola-like with several steps. Single-type and dual-type voids were found on the tip of FPDs and two heaves exist on the left and right sides of the void. All the results have proved that FPDs were void-type defects. These results are very useful to investigate FPDs in Cz-Si wafers further and explain the annihilation of FPDs during high-temperature annealing. 展开更多
关键词 flow pattern defects grown-in defects atomic force microscopy Czochralski-grown silicon
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Antihyperglycemic and antioxidant effects of Solanum xanthocarpum leaves(field grown & in vitro raised) extracts on alloxan induced diabetic rats 被引量:9
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作者 K Poongothai P Ponmurugan +2 位作者 K Syed Zameer Ahmed B Senthil Kumar SA Sheriff 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第10期778-785,共8页
Objective:To investigate antidiabetic efficacy of the extract of field grown and in vitro raised leaves of Solanum xanthocarpum(S.xanthocarpum) against alloxan induced diabetic rats. Methods:The antidiabetic activity ... Objective:To investigate antidiabetic efficacy of the extract of field grown and in vitro raised leaves of Solanum xanthocarpum(S.xanthocarpum) against alloxan induced diabetic rats. Methods:The antidiabetic activity of the crude methanol extracts of the field grown and in vitro raised leaves of S.xanthocarpum at different concentrations(100-200 mg/kg bw) was tested against alloxan induced diabetic rats.The antidiabetic efficacy was validated through various biochemical parameters and the antioxidant effect was also determined.The phytochemical analyses of field grown S.xanthocarpum and in vitro rasied 5.xanthocarpum leaves were done by estimating their chlorophyll,carotenoids,total sugar,protein,amino acid and minerals contents. Results:The results revealed that the methanol extracts of both the leaves(field grown and in vitro raised) of S.xanthocarpum was efficient anti hyperglycemic agents at a concentration of 200 mg/kg bw and posses potent antioxidant activity.However,the extracts of in vitro rasied S.xanthocarpum raised leaves exhibit higher efficacy than the field grown leaves in all tested concentrations.Proximal composition and mineral analysis of S.xanthocarpum revealed higher concentration of contents in in vitro rasied S.xanthocarpum than field grown S.xanthocarpum. Conclusions:From the results it can be concluded that the leaves extracts of S.xanthocarpum can be a potential candidate in treating the hyperglycemic conditions and suits to be an agent to reduce oxidative stress. 展开更多
关键词 SOLANUM Xanthocarpum ALLOXAN FIELD grown In vitro Oxidative stress Antioxidant HYPERGLYCEMIA HYPOLIPIDEMIC
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Influence of Surface Structures on Quality of CdTe(100) Thin Films Grown on GaAs(100) Substrates 被引量:2
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作者 Yi Gu Hui-Jun Zheng +3 位作者 Xi-Ren Chen Jia-Ming Li Tian-Xiao Nie Xu-Feng Kou 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第8期62-65,共4页
We report the epitaxial growth of single-crystalline Cd Te(100) thin films on Ga As(100) substrates using molecular beam epitaxy. By controlling the substrate pre-heated temperature with adjustable Te flux, three ... We report the epitaxial growth of single-crystalline Cd Te(100) thin films on Ga As(100) substrates using molecular beam epitaxy. By controlling the substrate pre-heated temperature with adjustable Te flux, three different reconstructed surfaces are realized, and their influence on the subsequent Cd Te growth is investigated. More importantly, we find that both the presence of a thin native oxide layer and the formation of Ga-As-Te bonds at the interface enable the growth along the(100) orientation and help to reduce the threading dislocations and other defects. Our results provide new opportunities for compound semiconductor heterogeneous growth via interfacial engineering. 展开更多
关键词 Thin Films grown on GaAs Te Ga SUBSTRATES Cd RHEED
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Fracture Mechanics,Crack Propagation and Microhardness Studies on Flux Grown ErAlO_3 Single Crystals 被引量:3
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作者 K.K.Bamzai and P.N.Kotru (Department of Physics, University of Jammu, Jammu 180006, India) B.M Wanklyn (Department of Physics, Clarendon Laboratory, Oxford University, Oxford OX1 3PU, U.K.) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第4期405-410,共6页
Results on fracture mechanics and crack propagation have been obtained, making use of Vickers microhardness studies on two different crystallographic planes [(110) and (001)] of flux grown erbium aluminate crystals in... Results on fracture mechanics and crack propagation have been obtained, making use of Vickers microhardness studies on two different crystallographic planes [(110) and (001)] of flux grown erbium aluminate crystals in the load ranging from 10-100 g. The variation of microhardness with load which is best explained by Hays and Kendall's law leads to the load independent values of hardness. Classification of cracks is dealt with and it is reported that the transition from Palmqvist to median types of cracks occurs at higher loads. The values of fracture toughness (K_C), and brittleness index (B_i) are calculated using median types of cracks. 展开更多
关键词 Fracture Mechanics Crack Propagation and Microhardness Studies on Flux grown ErAlO3 Single Crystals
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Chemical Forms of Selenium in Corn and Rice Grown in a High Selenium Area of China 被引量:7
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作者 M.A.BEILSTEIN P.D.WHANGER G.Q.YANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1991年第4期392-398,共7页
The chemical forms of selenium were determined in maize grown near Yutangba Village and in rice grown near Haubei village, Exi Prefecture, Enshi county of Hubei Province, China. The maize sample contained 18 ppm and t... The chemical forms of selenium were determined in maize grown near Yutangba Village and in rice grown near Haubei village, Exi Prefecture, Enshi county of Hubei Province, China. The maize sample contained 18 ppm and the rice samples an average of 3.6 ppm selenium. After they were ground to obtain a fine flour, this was acid hydrolyzed with hydrochloric acid in an inert atmosphere and the hydrolyzates chromatographed on columns of Dionex DC6A resin. The results indicate that the majority of the selenium is present as selenomethionine in both rice and corn. 展开更多
关键词 Chemical Forms of Selenium in Corn and Rice grown in a High Selenium Area of China
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Influence of Al Preflow Time on Surface Morphology and Quality of AlN and GaN on Si(111) Grown by MOCVD 被引量:1
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作者 刘波亭 马平 +2 位作者 李喜林 王军喜 李晋闽 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第5期119-123,共5页
We investigate the influence of A1 preflow time on surface morphology and quality of AIN and GaN. The AIN and GaN layers are grown on a Si (111) substrate by metal organic chemical vapor deposition. Scanning electro... We investigate the influence of A1 preflow time on surface morphology and quality of AIN and GaN. The AIN and GaN layers are grown on a Si (111) substrate by metal organic chemical vapor deposition. Scanning electron microscopy, atomic force microscopy, x-ray diffraction and optical microscopy are used for analysis. Consequently, we find significant differences in the epitaxial properties of AlN buffer and the GaN layer, which are dependent on the AI preflow time. A1 preflow layers act as nucleation sites in the case of AiN growth. Compact and uniform AIN nucleation sites are observed with optimizing A1 preflow at an early nucleation stage, which will lead to a smooth AIN surface. Trenches and AlN grain clusters appear on the AIN surface while meltoback etching occurs on the GaN surface with excessive A1 preflow. The GaN quality variation keeps a similar trend with the AIN quality, which is influenced by AI preflow. With an optimized duration orAl preflow, crystal quality and surface morphology of AIN and GaN could be improved. 展开更多
关键词 GAN ALN AIN grown by MOCVD Influence of Al Preflow Time on Surface Morphology and Quality of AlN and GaN on Si SI
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Enrichment of the less polar ginsenoside (Rg3) from ginseng grown in New Zealand by post-harvest processing and extraction 被引量:1
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作者 Wei Chen Wen-Liang Xu +2 位作者 Dan-Xia Shi Prabhu Balan David Popovich 《Traditional Medicine Research》 2021年第4期136-149,共14页
Background:Previous studies showed that New Zealand-grown ginseng contains an abundance of ginsenosides and that rare less polar ginsenosides,such as Rg3,exhibit more pharmacological activities than polar ginsenosides... Background:Previous studies showed that New Zealand-grown ginseng contains an abundance of ginsenosides and that rare less polar ginsenosides,such as Rg3,exhibit more pharmacological activities than polar ginsenosides,which are the major components of ginseng.Methods:The ginsenoside profile of New Zealand-grown Panax ginseng was manipulated by treatment with acetic acid,sodium hydroxide,pH,and high temperature.The abundance of 23 ginsenosides extracted by different treatments was quantified using high-performance liquid chromatography.Results:Treatment with 0.5 mol/L acetic acid can stimulate the degradation of polar ginsenosides to less polar ginsenosides(5.6%Rg3 was accumulated,P<0.0001).Furthermore,when ginseng root was treated at 121℃ for 100 min in a pH 3.0 acetic acid aqueous solution,the majority of the polar ginsenosides were converted into less polar ginsenosides.Specifically,83.46±3.69%(P=0.0360)of the less polar ginsenosides and 41.01±2.39%(P=0.0412)of Rg3 were enriched.In contrast,alkali treatment did not convert the polar ginsenosides into less polar ginsenosides at mild temperature and less conversion was observed compared with acid treatment at high temperature.Conclusion:This is the first attempt to manipulate the ginsenoside profile of New Zealand-grown ginseng.The conditions(high temperature with low pH)may be modified to produce and enrich the less polar ginsenoside fraction(especially Rg3)from the total ginseng extract. 展开更多
关键词 New Zealand grown ginseng Less polar ginsenoside Ginsenoside Rg3 Ginsenoside transformation
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Comparison of GaN/AlGaN/AlN/GaN HEMTs Grown on Sapphire with Fe-Modulation-Doped and Unintentionally Doped GaN Buffer:Material Growth and Device Fabrication 被引量:1
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作者 巩稼民 王权 +4 位作者 闫俊达 刘峰奇 冯春 王晓亮 王占国 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期99-103,共5页
AlGaN/GaN high electron mobility transistors (HEMTs) grown on Fe-modulation-doped (MD) and unintentionally doped (UID) GaN buffer layers are investigated and compared. Highly resistive GaN buffers (10^9Ω·... AlGaN/GaN high electron mobility transistors (HEMTs) grown on Fe-modulation-doped (MD) and unintentionally doped (UID) GaN buffer layers are investigated and compared. Highly resistive GaN buffers (10^9Ω·cm) are induced by individual mechanisms for the electron traps' formation: the Fe MD buffer (sample A) and the UID buffer with high density of edge-type dislocations (7.24×10^9cm^-2, sample B). The 300K Hall test indicates that the mobility of sample A with Fe doping (2503cm^2V^-1s^-1) is much higher than sample B (1926cm^2V^-1s^-1) due to the decreased scattering effect on the two-dimensional electron gas. HEMT devices are fabricated on the two samples and pulsed I–V measurements are conducted. Device A shows better gate pinch-off characteristics and a higher threshold voltage (-2.63V) compared with device B (-3.71V). Lower gate leakage current |IGS| of device A (3.32×10^-7A) is present compared with that of device B (8.29×10^-7A). When the off-state quiescent points Q_2 (V GQ2=-8V, V DQ2=0V) are on, V th hardly shifts for device A while device B shows +0.21V positive threshold voltage shift, resulting from the existence of electron traps associated with the dislocations in the UID-GaN buffer layer under the gate. Under pulsed I–V and transconductance G m–V GS measurement, the device with the Fe MD-doped buffer shows more potential in improving reliability upon off-state stress. 展开更多
关键词 GAN in HEMT is Comparison of GaN/AlGaN/AlN/GaN HEMTs grown on Sapphire with Fe-Modulation-Doped and Unintentionally Doped GaN Buffer:Material Growth and Device Fabrication of Fe with on
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Temperature-Dependent Photoluminescence Characteristics of InAs/GaAs Quantum Dots Directly Grown on Si Substrates
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作者 王霆 刘会赟 张建军 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第4期52-55,共4页
The first operation of an electrically pumped 1.3μm InAs/GaAs quantum-dot laser was previously reported epitaxially grown on Si (100) substrate. Here the direct epitaxial growth condition of 1.3μm InAs/OaAs quantu... The first operation of an electrically pumped 1.3μm InAs/GaAs quantum-dot laser was previously reported epitaxially grown on Si (100) substrate. Here the direct epitaxial growth condition of 1.3μm InAs/OaAs quantum on a Si substrate is further investigated using atomic force microscopy, etch pit density and temperature-dependent photoluminescence (PL) measurements. The PL for Si-based InAs/GaAs quantum dots appears to be very sensitive to the initial OaAs nucleation temperature and thickness with strongest room-temperature emission at 40000 (17Onto nucleation layer thickness), due to the lower density of defects generated under this growth condition, and stronger carrier confinement within the quantum dots. 展开更多
关键词 GAAS INAS Temperature-Dependent Photoluminescence Characteristics of InAs/GaAs Quantum Dots Directly grown on Si Substrates of SI on
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Characteristics of In_(0.52)Al_(0.48)As Grown on InP(100) Substrates by Molecular Beam Epitaxy: Growth Optimisation and Effects of Si Doping
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作者 S.F.Yoon(School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyng Avenue,Singapore 639798, Rep. of Singapore) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第2期91-98,共8页
Growth of In0.52Al0.48As epilayers on InP (100) substrates by molecular beam epitaxy at a wide range of substrate tempreatures (470~550℃) and at different Si doping levels has been carried out. Low temperature photol... Growth of In0.52Al0.48As epilayers on InP (100) substrates by molecular beam epitaxy at a wide range of substrate tempreatures (470~550℃) and at different Si doping levels has been carried out. Low temperature photoluminescence (PL) and double-axis X-ray diffraction (XRD) analyses shaw a strong dependence of the PL and XRD linewidths, XRD intensity ratio (Lepi/Isub), and lattice-mismatch on the substrate temperature. The X-ray diffraction peaks of samples grown at law temperatures show a composition of smaller peaks, indicating the presence of disorder due to alloy clustering. Raman scattering measurements of the same samples show an additional higher energy mode at 273 cm-1 in addition to the InAs-like and AlAs-like longitudinal-optic (LO) phonon modes. Samples doped with Si show an inverted S-shaped dependence of the PL peak energy variation with the temperature which weakens at high doping levels due to a possible reduction in the donor binding energy. Supported be observations of a reduction in both the AlAs-like and InAs-like LO phonon frequencies and a broadening of the LO phonon line shape as the doping level is increased, the PL intensity also shows in increasing degrees at higher doping levels, a temperature dependence which is characteristic of disordered and amorphous materials. 展开更多
关键词 As grown on InP Characteristics of In Growth Optimisation and Effects of Si Doping Substrates by Molecular Beam Epitaxy INP AL Si
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GaInP/GaInAs/GaInNAs/Ge Four-Junction Solar Cell Grown by Metal Organic Chemical Vapor Deposition with High Efficiency
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作者 张杨 王青 +5 位作者 张小宾 刘振奇 陈丙振 黄珊珊 彭娜 王智勇 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期167-171,共5页
We directly grow a lattice matched GalnP/GalnAs/GalnNAs/Ge (1.88 eVil .42 eVil .05 eV/0.67eV) four-junction (4J) solar cell on a Ge substrate by the metal organic chemical vapor deposition technology. To solve the... We directly grow a lattice matched GalnP/GalnAs/GalnNAs/Ge (1.88 eVil .42 eVil .05 eV/0.67eV) four-junction (4J) solar cell on a Ge substrate by the metal organic chemical vapor deposition technology. To solve the current limit of the GalnNAs sub cell, we design three kinds of anti-reflection coatings and adjust the base region thickness of the GalnNAs sub cell. Developed by a series of experiments, the external quantum efficiency of the GalnNAs sub cell exceeds 80%, and its current density reaches 11.24 mA/cm2. Therefore the current limit of the 4J solar cell is significantly improved. Moreover, we discuss the difference of test results between 4J and GalnP/GalnAs/Ge solar cells under the 1 sun AMO spectrum. 展开更多
关键词 by on it of GaInP/GaInAs/GaInNAs/Ge Four-Junction Solar Cell grown by Metal Organic Chemical Vapor Deposition with High Efficiency is THAN Ge GaAs with cell that
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Improved Semipolar(11(2|-)2) GaN Quality Grown on m-Plane Sapphire Substrates by Metal Organic Chemical Vapor Deposition Using Self-Organized SiN_x Interlayer
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作者 许晟瑞 赵颖 +3 位作者 姜腾 张进成 李培咸 郝跃 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期150-152,共3页
The effect of a self-organized SiNs interlayer on the defect density of (1122) semipolar GaN grown on 7n-plane sapphire is studied by transmission electron microscopy, atomic force microscopy and high resolution x-r... The effect of a self-organized SiNs interlayer on the defect density of (1122) semipolar GaN grown on 7n-plane sapphire is studied by transmission electron microscopy, atomic force microscopy and high resolution x-ray diffrac- tion. The SiNx interlayer reduces the c-type dislocation density from 2.5 ×10^10 cm^-2 to 5 ×10^8 cm 2. The SiNx interlayer produces regions that are free from basal plane stacking faults (BSFs) and dislocations. The overall BSF density is reduced from 2.1×10^5 cm-1 to 1.3×10^4 cm^-1. The large dislocations and BSF reduction in semipolar (1122) GaN with the SiNx, interlayer result from two primary mechanisms. The first mechanism is the direct dislocation blocking by the SiNx interlayer, and the second mechanism is associated with the unique structure character of (1122) semipolar GaN. 展开更多
关键词 GaN Quality grown on m-Plane Sapphire Substrates by Metal Organic Chemical Vapor Deposition Using Self-Organized SiN_x Interlaye in of is by Improved Semipolar on
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High-Performance In0.23Ga0.77As Channel MOSFETs with High Current Ratio Ion/Ioff Grown on Semi-insulating GaAs Substrates by MOCVD
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作者 孔祥挺 周旭亮 +4 位作者 李士颜 乔丽君 刘洪刚 王圩 潘教青 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第3期121-123,共3页
We demonstrate high-performance In0.23 Ga0.77 As channel metal-oxide-semiconductor field-effect transistors ( MOS- FETs) with high on-current to off-current (Ion/Ioff) ratio grown on semi-insulating GaAs wafers by... We demonstrate high-performance In0.23 Ga0.77 As channel metal-oxide-semiconductor field-effect transistors ( MOS- FETs) with high on-current to off-current (Ion/Ioff) ratio grown on semi-insulating GaAs wafers by metal-organic chemical vapor deposition (MOCVD). The 2μm channel-length devices exhibit a peak extrinsic transeonductance of 150 mS/mm and a drain current up to 500 mA/mm. The maximum effective mobility is 1680 cm2/Vs extracted by the split C-V method. Furthermore, the Ion/Ioff ratio is significantly improved from approximately 4.5 × 10^3 up to approximately 4.32 × 10^4 by controlling the etch thickness of In0.49Ga0.51P, The high drain current and high Ion/Ioff ratio of the In0.23Ga0.77As channel MOSFETs are achieved due to the high effective mobility and the low gate leakage current density. 展开更多
关键词 As Channel MOSFETs with High Current Ratio I MOSFET Ga grown on Semi-insulating GaAs Substrates by MOCVD off
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Effect of In_xGa_(1-x)As Interlayer on Surface Morphology and Optical Properties of GaSb/InGaAs Type-Ⅱ Quantum Dots Grown on InP (100) Substrates
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作者 陈虞龙 高优 +4 位作者 陈弘 张辉 何苗 李述体 郑树文 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第9期120-123,共4页
The effects of indium composition in InGaAs interlayer and on optical properties of GaSb/InGaAs QD material on morphology of GaSb/InGaAs quantum dots (QDs) system are studied. AFM images show that the change of the ... The effects of indium composition in InGaAs interlayer and on optical properties of GaSb/InGaAs QD material on morphology of GaSb/InGaAs quantum dots (QDs) system are studied. AFM images show that the change of the indium composition in InGaAs interlayer can alter the GaSb QD morphology. It is found that low indium composition in InGaAs interlayer can promote the formation of QDs, while high indium composition can inhibit the formation of QDs. The photoluminescence (PL) spectra of GaSb/InGaAs QDs at 8 K under low excitation power indicate that the third root of the excitation power is linear with the peak position, which provides a direct evidence for their luminescence belonging to type-Ⅱ material optical transition. The PL spectra at 8 K under an excitation power of 90row show that the optical properties of GaSb/InGaAs QD material system can be affected by the indium composition in the InGaAs interlayer, and the PL peak position is linear with the indium composition. The optical properties of GaSb/InGaAs QDs can be improved by adjusting the indium composition in the InGaAs interlayer. 展开更多
关键词 INGAAS in it GASB Quantum Dots grown on InP SUBSTRATES x)As Interlayer on Surface Morphology and Optical Properties of GaSb/InGaAs Type of on
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High-Quality and Strain-Relaxation GaN Epilayer Grown on SiC Substrates Using AIN Buffer and AlGaN Interlayer
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作者 Bo-Ting Liu Shi-Kuan Guo +2 位作者 Ping Ma Jun-Xi Wang Jin-Min Li 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第4期108-111,共4页
We study the effect of the AlGaN interlayer on structural quality and strain engineering of the GaN films grown on SiC substrates with an AlN buffer layer, hnproved structural quality and tensile stress releasing are ... We study the effect of the AlGaN interlayer on structural quality and strain engineering of the GaN films grown on SiC substrates with an AlN buffer layer, hnproved structural quality and tensile stress releasing are realized in unintentionally doped GaN thin films grown on 6H-SiC substrates by metal organic chemical vapor deposition. Using the optimized AlGaN interlayer, we find that the full width at half maximum of x-ray diffraction peaks for GaN decreases dramatically, indicating an improved crystalline quality. Meanwhile, it is revealed that the biaxial tensile stress in the GaN film is significantly reduced from the Raman results. Photoluminescence spectra exhibit a shift of the peak position of the near-band-edge emission, as well as the integrated intensity ratio variation of the near-band-edge emission to the yellow luminescence band. Thus by optimizing the AlGaN interlayer, we could acquire the high-quality and strain-relaxation GaN epilayer with large thickness on SiC substrates. 展开更多
关键词 ALGAN In High-Quality and Strain-Relaxation GaN Epilayer grown on SiC Substrates Using AIN Buffer and AlGaN Interlayer SiC AIN
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Inhomogeneity of Rare Earth Doped Ⅲ-Ⅴ Compounds Grown by LPE
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作者 Yuan Yourong He Shengfu +5 位作者 Zhu Youcai,Li Xiangwen Zhao Yu Du Shuqin Shi Yihe Liu Guoyuan Li Yunyi Zhou Ji Changchun Institute of Physics,Academia Sinica 130021 China General Research Institute for Non-ferrous Metals,Beijing 100088 Department of Chemistry, Peking University 《Rare Metals》 SCIE EI CAS CSCD 1990年第2期145-149,共5页
The processing of InP, GaAs and related compounds doped with rare earth metals, such as Er, Nd and Gd, grown by LPE is described. The inhomogeneity of rare earth heavily doped epi-layers is studied by SIMS, SEM and X-... The processing of InP, GaAs and related compounds doped with rare earth metals, such as Er, Nd and Gd, grown by LPE is described. The inhomogeneity of rare earth heavily doped epi-layers is studied by SIMS, SEM and X-ray diffraction techniques. 展开更多
关键词 GAAS Inhomogeneity of Rare Earth Doped Compounds grown by LPE
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Analysis on Quality of Coptis chinensis Grown under Different Woods
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作者 Zhen SHEN Wenlong WAN 《Medicinal Plant》 CAS 2018年第4期80-82,共3页
[Objectives] To analyze the quality of Coptis chinensis grown under woods of Magnolia officinalis Rehd. et Wils.,Platycladus orientalis( Linn.) Franco.,and Cunninghamia lanceolata( Lamb.). [Methods] The content of fiv... [Objectives] To analyze the quality of Coptis chinensis grown under woods of Magnolia officinalis Rehd. et Wils.,Platycladus orientalis( Linn.) Franco.,and Cunninghamia lanceolata( Lamb.). [Methods] The content of five kinds of alkaloids in C. chinensis grown under three different woods was determined by high-performance liquid chromatography( HPLC). Detection conditions: 0. 03 mol/L methanol and potassium dihydrogen phosphate solution( volume ratio of 65∶ 35) as the mobile phase,flow rate of 1. 0 mL/min,detection wavelength of 350 nm,and column temperature of 35℃. [Results] In these three woods,the quality of C. chinensis grown under P. orientalis woods was the highest. [Conclusions] This study is expected to provide certain references for cultivation and planting of C. chinensis under woods. 展开更多
关键词 HPLC Coptis chinensis grown under woods ALKALOIDS
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