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Comparative evaluation of commercial Douchi by different molds:biogenic amines,non-volatile and volatile compounds 被引量:1
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作者 Aijun Li Gang Yang +4 位作者 Zhirong Wang Shenglan Liao Muying Du Jun Song Jianquan Kan 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期434-443,共10页
To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fer... To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fermentation of Douchi.The results showed that the biogenic amine contents of the three types of Douchi were all within the safe range and far lower than those of traditional fermented Douchi.Aspergillus-type Douchi produced more free amino acids than the other two types of Douchi,and its umami taste was more prominent in sensory evaluation(P<0.01),while Mucor-type and Rhizopus-type Douchi produced more esters and pyrazines,making the aroma,sauce,and Douchi flavor more abundant.According to the Pearson and PLS analyses results,sweetness was significantly negatively correlated with phenylalanine,cysteine,and acetic acid(P<0.05),bitterness was significantly negatively correlated with malic acid(P<0.05),the sour taste was significantly positively correlated with citric acid and most free amino acids(P<0.05),while astringency was significantly negatively correlated with glucose(P<0.001).Thirteen volatile compounds such as furfuryl alcohol,phenethyl alcohol,and benzaldehyde caused the flavor difference of three types of Douchi.This study provides theoretical basis for the selection of starting strains for commercial Douchi production. 展开更多
关键词 DOUCHI Starting strains non-volatile compounds Volatile compounds Sensory evaluation
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Correlation of gut microorganisms and non-volatile flavor substances provides new insights for breeding Scylla paramamosain
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作者 Gao GAO Xing LI +7 位作者 Kangxiang QIN Yun HU Xiaosong JIANG Chenxi CHE Yuntao LI Changkao MU Chunlin WANG Huan WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1336-1347,共12页
The farming of Scylla paramamosain with specific flavors has a higher commercial value,and the flavors are related to the integrated farming environment and non-volatile flavor substances,while the survival environmen... The farming of Scylla paramamosain with specific flavors has a higher commercial value,and the flavors are related to the integrated farming environment and non-volatile flavor substances,while the survival environment is one of the important ways to source gut microorganisms in the organism.In this study,the levels of dominant taxa in the gut flora of S.paramamosain from Mong Cai,Vietnam(VN),Taishan City,Guangdong Province(TS)of China,and Ninghai County,Ningbo City(NB)Zhejiang Province of China converged with those of S.paramamosain from Sanmen County,Ningbo City(CK 1,CK 2,and CK 3)at 28 d of domestication.The top 15 genera with the highest abundance of VN,TS,and NB gut flora were the same as CK 1,CK 2,and CK 3,but with different percentages,and gradually converged to CK 1,CK 2,and CK 3,respectively,at 28 d of domestication.Correlation between intestinal flora and non-volatile flavor substances in the hepatopancreas at the percentage level of relative abundance of bacterial genera found that above 28 d of domestication,Muribaculaceae,Psychrilyobacter,Clostridia_vadinBB 60_group,Halarcobacter Carboxylicivirga,Sediminispirochaeta may be the most important genera affecting flavor amino acids of VN.Sediminispirochaeta,Carboxylicivirga,Halarcobacter,Photobacterium,ZOR 0006,Psychrilyobacter,and Pseudomonas may be the most important genera affecting flavor amino acids of NB.Sediminispirochaeta,Carboxylicivirga,Halarcobacter,Photobacterium,ZOR 0006,Vibrio,and Sphingomonas may be the most important genera affecting flavor amino acids of TS.These results show that the intestinal flora structure of crabs from different areas were domesticated in the same area for at least 28 d before they converged to that of the domesticated crab,and the most important genera affecting the flavor amino acids of TS,VN,and NB were also identified.The results of this study provide a reference and basis for the technique of directional cultivation of the flavor quality of the crab. 展开更多
关键词 survival environment Scylla paramamosain intestinal flora structure non-volatile flavor substance directional breeding
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A Low-Power,Single-Poly,Non-Volatile Memory for Passive RFID Tags 被引量:1
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作者 赵涤燹 闫娜 +3 位作者 徐雯 杨立吾 王俊宇 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第1期99-104,共6页
Single-poly,576bit non-volatile memory is designed and implemented in an SMIC 0.18μm standard CMOS process for the purpose of reducing the cost and power of passive RFID tag chips. The memory bit cell is designed wit... Single-poly,576bit non-volatile memory is designed and implemented in an SMIC 0.18μm standard CMOS process for the purpose of reducing the cost and power of passive RFID tag chips. The memory bit cell is designed with conventional single-poly pMOS transistors, based on the bi-directional Fowler-Nordheim tunneling effect, and the typical program/erase time is 10ms for every 16bits. A new ,single-ended sense amplifier is proposed to reduce the power dissipation in the current sensing scheme. The average current consumption of the whole memory chip is 0.8μA for the power supply voltage of 1.2V at a reading rate of 640kHz. 展开更多
关键词 RFID single-poly non-volatile memory standard CMOS process sense amplifier low power
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Correlation between dominant bacterial community and non-volatile organic compounds during the fermentation of shrimp sauces 被引量:3
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作者 Ruichang Gao Huijie Liu +3 位作者 Ying Li Hongying Liu Yue Zhou Li Yuan 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期233-241,共9页
Shrimp sauce,one of the traditional salt-fermented food in China,has a unique flavor that is influenced by the resident microflora.The quality of salt-fermented shrimp sauce was evaluated in this work by determining t... Shrimp sauce,one of the traditional salt-fermented food in China,has a unique flavor that is influenced by the resident microflora.The quality of salt-fermented shrimp sauce was evaluated in this work by determining the total volatile basic nitrogen(TVB-N),the amino acid nitrogen(AAN),organic acid,5’-nucleotide and free amino acids(FAA).Moreover,the dynamics of microbial diversity during processing was investigated by using high-throughput sequencing technology.The results showed that the AAN,TVB-N,organic acid,5’-nucleotide and FAA content were in range of 0.93-1.42 g/100 mL,49.91-236.27 mg/100 mL,6.65-20.68 mg/mL,3.51-6.56 mg/mL and 81.27-102.90 mg/mL.Among the microbial diversity found in the shrimp sauce,Tetragenococcus,Flavobacterium,Polaribacter,Haematospirillum and Staphylococcus were the predominant genera.Correlation analysis indicated that the bacteria Tetragenococcus and Staphylococcus were important in the formation of non-volatile compounds.Tetragenococcus positively correlated with a variety of FAAs;Staphylococcus positively correlated with 5’-nucleotides.The analysis indicated that Tetragenococcus and Staphylococcus were the core genera affecting non-volatile components.These findings indicate the dynamics of the bacterial community and non-volatile components inter-relationships during shrimp sauce fermentation and provide a theoretical basis for improving the fermentation process of shrimp sauce. 展开更多
关键词 Shrimp sauces non-volatile compounds Bacterial community Electronic tongue Correlation analysis
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Overview of one transistor type of hybrid organic ferroelectric non-volatile memory 被引量:3
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作者 Young Tea Chun Daping Chu 《Instrumentation》 2015年第1期65-74,共10页
Organic ferroelectric memory devices based on field effect transistors that can be configured between two stable states of on and off have been widely researched as the next generation data storage media in recent yea... Organic ferroelectric memory devices based on field effect transistors that can be configured between two stable states of on and off have been widely researched as the next generation data storage media in recent years.This emerging type of memory devices can lead to a new instrument system as a potential alternative to previous non-volatile memory building blocks in future processing units because of their numerous merits such as cost-effective process,simple structure and freedom in substrate choices.This bi-stable non-volatile memory device of information storage has been investigated using several organic or inorganic semiconductors with organic ferroelectric polymer materials.Recent progresses in this ferroelectric memory field,hybrid system have attracted a lot of attention due to their excellent device performance in comparison with that of all organic systems.In this paper,a general review of this type of ferroelectric non-volatile memory is provided,which include the device structure,organic ferroelectric materials,electrical characteristics and working principles.We also present some snapshots of our previous study on hybrid ferroelectric memories including our recent work based on zinc oxide nanowire channels. 展开更多
关键词 ORGANIC FERROELECTRIC field effect TRANSISTOR non-volatile MEMORY HYBRID
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Formation of high density TiN nanocrystals and its application in non-volatile memories
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作者 李学林 冯顺山 陈国光 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期1070-1077,共8页
Non-volatile memory based on TiN nanocrystal (TiN-NC) charge storage nodes embedded in SiO2 has been fabricated and its electrical properties have been measured. It was found that the density and size distribution o... Non-volatile memory based on TiN nanocrystal (TiN-NC) charge storage nodes embedded in SiO2 has been fabricated and its electrical properties have been measured. It was found that the density and size distribution of TiN-NCs can be controlled by annealing temperature. The formation of well separated crystalline TiN nano-dots with an average size of 5 nm is confirmed by transmission electron microscopy and x-ray diffraction, x-ray photoelectron spectroscopy confirms the existence of a transition layer of TiNxOy/SiON oxide between TiN-NC and SiO2, which reduces the barrier height of tunnel oxide and thereby enhances programming/erasing speed. The memory device shows a memory window of 2.5V and an endurance cycle throughout 10^5. Its charging mechanism, which is interpreted from the analysis of programming speed (dVth/dt) and the gate leakage versus voltage characteristics (Ig vs Vg), has been explained by direct tunnelling for tunnel oxide and Fowler Nordheim tunnelling for control oxide at programming voltages lower than 9V, and by Fowler-Nordheim tunnelling for both the oxides at programming voltages higher than 9V. 展开更多
关键词 TiN nanocrystal SIZE DENSITY non-volatile memory application
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Molecular dynamics simulations on the wet/dry self-latching and electric fields triggered wet/dry transitions between nanosheets:A non-volatile memory nanostructure
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作者 Jianzhuo Zhu Xinyu Zhang +1 位作者 Xingyuan Li Qiuming Peng 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第2期135-139,共5页
We design a nanostructure composing of two nanoscale graphene sheets parallelly immersed in water.Using molecular dynamics simulations,we demonstrate that the wet/dry state between the graphene sheets can be self-latc... We design a nanostructure composing of two nanoscale graphene sheets parallelly immersed in water.Using molecular dynamics simulations,we demonstrate that the wet/dry state between the graphene sheets can be self-latched;moreover,the wet→dry/dry→wet transition takes place when applying an external electric field perpendicular/parallel to the graphene sheets(E;/E;).This structure works like a flash memory device(a non-volatile memory):the stored information(wet and dry states)of the system can be kept spontaneously,and can also be rewritten by external electric fields.On the one hand,when the distance between the two nanosheets is close to a certain distance,the free energy barriers for the transitions dry→wet and wet→dry can be quite large.As a result,the wet and dry states are self-latched.On the other hand,an E;and an E;will respectively increase and decrease the free energy of the water located in-between the two nanosheets.Consequently,the wet→dry and dry→wet transitions are observed.Our results may be useful for designing novel information memory devices. 展开更多
关键词 wet/dry properties non-volatile memory nanostructure molecular dynamics simulations
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Wedge-shaped HfO_(2) buffer layer-induced field-free spin-orbit torque switching of HfO_(2)/Pt/Co structure 被引量:1
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作者 陈建辉 梁梦凡 +4 位作者 宋衍 袁俊杰 张梦旸 骆泳铭 王宁宁 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期662-667,共6页
Field-free spin-orbit torque(SOT)switching of perpendicular magnetization is essential for future spintronic devices.This study demonstrates the field-free switching of perpendicular magnetization in an HfO_(2)/Pt/Co/... Field-free spin-orbit torque(SOT)switching of perpendicular magnetization is essential for future spintronic devices.This study demonstrates the field-free switching of perpendicular magnetization in an HfO_(2)/Pt/Co/TaO_(x) structure,which is facilitated by a wedge-shaped HfO_(2)buffer layer.The field-free switching ratio varies with HfO_(2)thickness,reaching optimal performance at 25 nm.This phenomenon is attributed to the lateral anisotropy gradient of the Co layer,which is induced by the wedge-shaped HfO_(2)buffer layer.The thickness gradient of HfO_(2)along the wedge creates a corresponding lateral anisotropy gradient in the Co layer,correlating with the switching ratio.These findings indicate that field-free SOT switching can be achieved through designing buffer layer,offering a novel approach to innovating spin-orbit device. 展开更多
关键词 spin-orbit torque field-free switching HfO_(2) buffer layer
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An Overview of Non-Volatile Flip-Flops Based on Emerging Memory Technologies(Invited paper)
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作者 J.M.Portal M.Bocquet +8 位作者 M.Moreau H.Aziza D.Deleruyelle Y.Zhang W.Kang J.-O.Klein Y.-G.Zhang C.Chappert W.-S.Zhao 《Journal of Electronic Science and Technology》 CAS 2014年第2期173-181,共9页
Low power consumption is a major issue in nowadays electronics systems. This trend is pushed by the development of data center related to cloud services and soon to the Internet of Things (IoT) deployment. Memories ... Low power consumption is a major issue in nowadays electronics systems. This trend is pushed by the development of data center related to cloud services and soon to the Internet of Things (IoT) deployment. Memories are one of the major contributors to power consumption. However, the development of emerging memory technologies paves the way to low-power design, through the partial replacement of the dynamic random access memory (DRAM) with the non-volatile stand-alone memory in servers or with the embedded or distributed emerging non-volatile memory in IoT objects. In the latter case, non-volatile flip-flops (NVFFs) seem a promising candidate to replace the retention latch. Indeed, IoT objects present long sleep time and NVFFs offer to save data in registers with zero power when the application is idle. This paper gives an overview of NVFF architecture flavors for various emerging memory technologies. 展开更多
关键词 Emerging memory technology ferroelectric RAM low power magnetic RAM non-volatile flip-flops phase change RAM resistive RAM
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The Electric-Field Controllable Non-Volatile 35° Rotation of Magnetic Easy Axis in Magnetoelectric CoFeB/(001)-Cut Pb(Mg_(1/3)Nb_(2/3))O_3-25%PbTiO_3 Heterostructure
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作者 何浩 赵江涛 +6 位作者 罗震林 杨远俊 徐晗 洪宾 王亮鑫 王瑞雪 高琛 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期141-144,共4页
Using in situ electric-field-modulated anisotropic magnetoresistance measurement, a large reversible and non- volatile in-plane rotation of magnetic easy axis of -35° between the positive and negative electrical ... Using in situ electric-field-modulated anisotropic magnetoresistance measurement, a large reversible and non- volatile in-plane rotation of magnetic easy axis of -35° between the positive and negative electrical poling states is demonstrated in C040Fe40B20//(001)-cut Pb(Mgl/3Nb2/3)O3-25PbTiO3 (PMN-PT). The specific magneto- electric coupling mechanism therein is experimentally verified to be related to the synchronous in-plane strain rotation induced by 109° ferroelastic domain switching in the (001)-cut PMN-PT substrate. 展开更多
关键词 in PT is of PMN O3-25%PbTiO3 Heterostructure Rotation of Magnetic Easy Axis in Magnetoelectric CoFeB The Electric-Field Controllable non-volatile 35 Mg Nb
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Design of an Electrically Written and Optically Read Non-volatile Memory Device Employing BiFeO3/Au Heterostructures with Strong Absorption Resonance
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作者 肖鹏博 张伟 +2 位作者 曲天良 黄云 胡绍民 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期67-70,共4页
Exploiting new concepts for dense, fast, and nonvolatile random access memory with reduced energy consump- tion is a significant issue for information technology. Here we design an 'electrically written and optically... Exploiting new concepts for dense, fast, and nonvolatile random access memory with reduced energy consump- tion is a significant issue for information technology. Here we design an 'electrically written and optically read' information storage device employing BiFeO3/A u heterostruetures with strong absorption resonance. The electro- optic effect is the basis for the device design, which arises from the strong absorption resonance in BiFeO3/Au heterostructures and the electrically tunable significant birefringence of the BiFeO3 film. We first construct a sim- ulation calculation of the BiFeO3/Au structure spectrum and identify absorption resonance and electro-optical modulation characteristics. Following a micro scale partition, the surface reflected light intensity of different polarization units is calculated. The results depend on electric polarization states of the BiFeO3 film, thus BiFeO3/Au heterostructures can essentially be designed as a type of electrically written and optically read infor- mation storage device by utilizing the scanning near-field optical microscopy technology based on the conductive silicon cantilever tip with nanofabricated aperture. This work will shed light on information storage technology. 展开更多
关键词 BFO Design of an Electrically Written and Optically Read non-volatile Memory Device Employing BiFeO3/Au Heterostructures with Strong Absorption Resonance
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A Low Power Non-Volatile LR-WPAN Baseband Processor with Wake-Up Identification Receiver
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作者 YU Shuangming FENG Peng WU Nanjian 《China Communications》 SCIE CSCD 2016年第1期33-46,共14页
The paper proposes a low power non-volatile baseband processor with wake-up identification(WUI) receiver for LR-WPAN transceiver.It consists of WUI receiver,main receiver,transmitter,non-volatile memory(NVM) and power... The paper proposes a low power non-volatile baseband processor with wake-up identification(WUI) receiver for LR-WPAN transceiver.It consists of WUI receiver,main receiver,transmitter,non-volatile memory(NVM) and power management module.The main receiver adopts a unified simplified synchronization method and channel codec with proactive Reed-Solomon Bypass technique,which increases the robustness and energy efficiency of receiver.The WUI receiver specifies the communication node and wakes up the transceiver to reduce average power consumption of the transceiver.The embedded NVM can backup/restore the states information of processor that avoids the loss of the state information caused by power failure and reduces the unnecessary power of repetitive computation when the processor is waked up from power down mode.The baseband processor is designed and verified on a FPGA board.The simulated power consumption of processor is 5.1uW for transmitting and 28.2μW for receiving.The WUI receiver technique reduces the average power consumption of transceiver remarkably.If the transceiver operates 30 seconds in every 15 minutes,the average power consumption of the transceiver can be reduced by two orders of magnitude.The NVM avoids the loss of the state information caused by power failure and energy waste caused by repetitive computation. 展开更多
关键词 LR-WPAN wake-up identification receiver synchronization non-volatile memory baseband processor digital integrated circuit low power chip design
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Impact response and energy absorption of metallic buffer with entangled wire mesh damper
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作者 Chao Zheng Jun Wu +1 位作者 Mangong Zhang Xin Xue 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期137-150,共14页
An innovative metallic buffer consisting of series-connected hat-shaped entangled wire mesh damper(EWMD)and parallel springs are proposed in this work to enhance the reliability of engineering equipment.The impact res... An innovative metallic buffer consisting of series-connected hat-shaped entangled wire mesh damper(EWMD)and parallel springs are proposed in this work to enhance the reliability of engineering equipment.The impact response and the energy dissipation mechanism of hat-shaped EWMD under different quasi-static compression deformations(2-7 mm)and impact heights(100-200 mm)are investigated using experimental and numerical methods.The results demonstrate distinct stages in the quasi-static mechanical characteristics of hat-shaped EWMD,including stiffness softening,negative stiffness,and stiffness hardening.The loss factor gradually increases with increasing compression deformation before entering the stiffness hardening stage.Under impact loads,the hat-shaped EWMD exhibits optimal impact energy absorption when it enters the negative stiffness stage(150 mm),resulting in the best impact isolation effect of metallic buffer.However,the impact energy absorption significantly decreases when hat-shaped EWMD enters the stiffness hardening stage.Interestingly,quasi-static compression analysis after experiencing different impact loads reveals the disappearance of the negative stiffness phenomenon.Moreover,with increasing impact loads,the stiffness hardening point progressively shifts to an earlier stage. 展开更多
关键词 Metallic buffer Hat-shaped EWMD Drop impact Energy absorption characteristics Mechanical behavior
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Irrigation and Thermal Buffering Using Mathematical Modeling
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作者 Yara Yasser Elborolosy Harsho Sanyal Joseph Cataldo 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期19-32,共14页
Two methods of irrigation,drip,and sprinkler were studied to determine the response of the Javits green roof to irrigation.The control study was dry unirrigated plots.Drip irrigation consisted of irrigation tubes runn... Two methods of irrigation,drip,and sprinkler were studied to determine the response of the Javits green roof to irrigation.The control study was dry unirrigated plots.Drip irrigation consisted of irrigation tubes running through the green roof that would water the soil throughout and sprinkler irrigation used a sprinkler system to irrigate the green roof from above.In all cases,the irrigated roofs had increased the soil moisture,reduced temperatures of both the upper and lower surfaces,reduced growing medium temperatures and reduced air temperatures above the green roof relative to the unirrigated roof.The buffered temperature fluctuations were also studied via air conditioner energy consumption.There was a 28%reduction in air conditioner energy consumption and a 33%reduction in overall energy consumption between dry and irrigated plots.Values of thermal resistance or S were determined for accuracy and for this study,there was little change which is ideal.A series of infra-red and thermal probe measurements were used to determine temperatures in the air and sedum.It was determined that the sprinkler irrigation did a better job than the drip irrigation in keeping cooler temperatures within the green roof.A Mann-Whitney U test was performed to verify the variation in moisture temperatures buffering energy consumption.By getting a p-value<0.05,it indicates that the model is accurate for prediction and medium temperatures were statistically different. 展开更多
关键词 Green roofs IRRIGATION DRIP SPRINKLER Thermal buffering
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Non-destructive buffer enabling near-infrared-transparent inverted inorganic perovskite solar cells toward 1400 h light-soaking stable perovskite/Cu(In,Ga)Se_(2) tandem solar cells
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作者 Yu Zhang Zhaoheng Tang +14 位作者 Zhongyang Zhang Jiahong Tang Minghua Li Siyuan Zhu Wenyan Tan Xi Jin Tongsheng Chen Jinsong Hu Chao Zhou Chunlei Yang Qijie Liang Xugang Guo Weimin Li Weiqiang Chen Yan Jiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期622-629,I0013,共9页
Near-infrared(NIR)transparent inverted all-inorganic perovskite solar cells(PSCs)are excellent top cell candidates in tandem applications.An essential challenge is the replacement of metal contacts with transparent co... Near-infrared(NIR)transparent inverted all-inorganic perovskite solar cells(PSCs)are excellent top cell candidates in tandem applications.An essential challenge is the replacement of metal contacts with transparent conductive oxide(TCO)electrodes,which requires the introduction of a buffer layer to prevent sputtering damage.In this study,we show that the conventional buffers(i.e.,small organic molecules and atomic layer deposited metal oxides)used for organic-inorganic hybrid perovskites are not applicable to all-inorganic perovskites,due to non-uniform coverage of the vulnerable layers underneath,deterioration upon ion bombardment and moisture induced perovskite phase transition,A thin film of metal oxide nanoparticles by the spin-coating method serves as a non-destructive buffer layer for inorganic PSCs.All-inorganic inverted near-infrared-transparent PSCs deliver a PCE of 17.46%and an average transmittance of 73.7%between 780 and 1200 nm.In combination with an 18.56%Cu(In,Ga)Se_(2) bottom cell,we further demonstrate the first all-inorganic perovskite/CIGS 4-T tandem solar cell with a PCE of 24.75%,which exhibits excellent illumination stability by maintaining 86.7%of its initial efficiency after 1400 h.The non-destructive buffer lays the foundation for efficient and stable NIR-transparent inverted inorganic perovskite solar cells and perovskite-based tandems. 展开更多
关键词 CsPbI_(3)perovskite Inverted perovskite solar cells Tandem solar cells buffer layer Stability
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Fast UAV path planning in urban environments based on three-step experience buffer sampling DDPG
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作者 Shasha Tian Yuanxiang Li +4 位作者 Xiao Zhang Lu Zheng Linhui Cheng Wei She Wei Xie 《Digital Communications and Networks》 SCIE CSCD 2024年第4期813-826,共14页
The path planning of Unmanned Aerial Vehicle(UAV)is a critical issue in emergency communication and rescue operations,especially in adversarial urban environments.Due to the continuity of the flying space,complex buil... The path planning of Unmanned Aerial Vehicle(UAV)is a critical issue in emergency communication and rescue operations,especially in adversarial urban environments.Due to the continuity of the flying space,complex building obstacles,and the aircraft's high dynamics,traditional algorithms cannot find the optimal collision-free flying path between the UAV station and the destination.Accordingly,in this paper,we study the fast UAV path planning problem in a 3D urban environment from a source point to a target point and propose a Three-Step Experience Buffer Deep Deterministic Policy Gradient(TSEB-DDPG)algorithm.We first build the 3D model of a complex urban environment with buildings and project the 3D building surface into many 2D geometric shapes.After transformation,we propose the Hierarchical Learning Particle Swarm Optimization(HL-PSO)to obtain the empirical path.Then,to ensure the accuracy of the obtained paths,the empirical path,the collision information and fast transition information are stored in the three experience buffers of the TSEB-DDPG algorithm as dynamic guidance information.The sampling ratio of each buffer is dynamically adapted to the training stages.Moreover,we designed a reward mechanism to improve the convergence speed of the DDPG algorithm for UAV path planning.The proposed TSEB-DDPG algorithm has also been compared to three widely used competitors experimentally,and the results show that the TSEB-DDPG algorithm can archive the fastest convergence speed and the highest accuracy.We also conduct experiments in real scenarios and compare the real path planning obtained by the HL-PSO algorithm,DDPG algorithm,and TSEB-DDPG algorithm.The results show that the TSEBDDPG algorithm can archive almost the best in terms of accuracy,the average time of actual path planning,and the success rate. 展开更多
关键词 Unmanned aerial vehicle Path planning Deep deterministic policy gradient Three-step experience buffer Particle swarm optimization
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Numerical Study and Optimization of CZTS-Based Thin-Film Solar Cell Structure with Different Novel Buffer-Layer Materials Using SCAPS-1D Software
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作者 Md. Zamil Sultan Arman Shahriar +4 位作者 Rony Tota Md. Nuralam Howlader Hasibul Haque Rodro Mahfuja Jannat Akhy Md. Abir Al Rashik 《Energy and Power Engineering》 2024年第4期179-195,共17页
This study explored the performances of CZTS-based thin-film solar cell with three novel buffer layer materials ZnS, CdS, and CdZnS, as well as with variation in thickness of buffer and absorber-layer, doping concentr... This study explored the performances of CZTS-based thin-film solar cell with three novel buffer layer materials ZnS, CdS, and CdZnS, as well as with variation in thickness of buffer and absorber-layer, doping concentrations of absorber-layer material and operating temperature. Our aims focused to identify the most optimal thin-film solar cell structure that offers high efficiency and lower toxicity which are desirable for sustainable and eco-friendly energy sources globally. SCAPS-1D, widely used software for modeling and simulating solar cells, has been used and solar cell fundamental performance parameters such as open-circuited voltage (), short-circuited current density (), fill-factor() and efficiency() have been optimized in this study. Based on our simulation results, it was found that CZTS solar cell with Cd<sub>0.4</sub>Zn<sub>0.6</sub>S as buffer-layer offers the most optimal combination of high efficiency and lower toxicity in comparison to other structure investigated in our study. Although the efficiency of Cd<sub>0.4</sub>Zn<sub>0.6</sub>S, ZnS and CdS are comparable, Cd<sub>0.4</sub>Zn<sub>0.6</sub>S is preferable to use as buffer-layer for its non-toxic property. In addition, evaluation of performance as a function of buffer-layer thickness for Cd<sub>0.4</sub>Zn<sub>0.6</sub>S, ZnS and CdS showed that optimum buffer-layer thickness for Cd<sub>0.4</sub>Zn<sub>0.6</sub>S was in the range from 50 to 150nm while ZnS offered only 50 – 75 nm. Furthermore, the temperature dependence performance parameters evaluation revealed that it is better to operate solar cell at temperature 290K for stable operation with optimum performances. This study would provide valuable insights into design and optimization of nanotechnology-based solar energy technology for minimizing global energy crisis and developing eco-friendly energy sources sustainable and simultaneously. 展开更多
关键词 Thin-Film Solar Cell CZTS buffer-Layer Renewable Energy Green-House Gases Efficiency
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Acid Buffering Capacity of Forest Litter from Some ImportantPlantation and Natural Forests in South China 被引量:6
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作者 李志安 曹裕松 +2 位作者 邹碧 丁永祯 任海 《Acta Botanica Sinica》 CSCD 2003年第12期1398-1407,共10页
The role of forest litter as an acid-base buffering system was assessed by litter from plantation and natural forests in South China. Samples were either extracted with acid solutions or titrated with acid or base sol... The role of forest litter as an acid-base buffering system was assessed by litter from plantation and natural forests in South China. Samples were either extracted with acid solutions or titrated with acid or base solutions. Litter was found to be a strong acid-base buffering system. Two legume species, Acacia mangium Willd and A. auriculaiformis A. Cunn, had very high litter pH values of around 6, which was 2 pH units higher than that of the soil where they grew. Litter of all other plantation species had litter pH of around 4, similar to that of the soil. Both legume species have high potential to neutralize soil acidity and the litter layer could act to shield soil against acid rain. The current stand of two legume species was estimated to be able to raise rain acidity by 0.1 to 0.4 pH units. Inorganic ions did not fully explain the pH pattern of different litter extracts, but high sodium and low nitrate partly accounted for the high pH of the two legume species. Some natural forest species had extremely low pH. As a whole, the litter of the natural climax forest was the driving force of soil acidification. Although plant residues are strong acid-base buffering system and able to adjust acidity of environment, only a few species can be expected to make soil more acid or alkaline through this mechanism since most species have litter pH values similar to those of soil where they grow. 展开更多
关键词 acid-base buffer system inorganic ions acid rain forest litter legume species
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Organic Photovoltaic Cells with Improved Performance Using Bathophenanthroline as a Buffer Layer 被引量:5
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作者 王娜娜 于军胜 +1 位作者 林慧 蒋亚东 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期84-88,I0002,共6页
The role of bathophenanthroline (Bphen) as a buffer layer inserted between fullerene (C60) and Ag cathode in organic photovoltaic (OPV) cell was discussed. By introducing Bphen as a buffer layer with thicknes fr... The role of bathophenanthroline (Bphen) as a buffer layer inserted between fullerene (C60) and Ag cathode in organic photovoltaic (OPV) cell was discussed. By introducing Bphen as a buffer layer with thicknes from 0 to 2.5 nm, the power conversion efficiency of the OPV cell based on copper phthalocyanine (CuPc) and C60 was increased from 0.87% to 2.25% under AM 1.5 solar illumination at an intensity of 100 mW/cm^2, which was higher than that of bathocuproine used as a buffer layer. The photocurrent-voltage characteristics showed that Bphen effectively improves electron transport through C60 layer into Ag electrode and leads to balance charge carrier transport capability. The influence of Bphen thickness on OPV cells was also investigated. Furthermore, the absorption spectrum shows that an additional Bphen layer enhances the light harvest capability of CuPc/C60. 展开更多
关键词 Organic photovoltaic cell buffer layer Bathophenanthroline Charge carrier transport
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基于PC图形卡W-Buffer的交互直接体绘制 被引量:1
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作者 袁非牛 周荷琴 +1 位作者 冯焕清 梅涛 《中国科学技术大学学报》 CAS CSCD 北大核心 2003年第4期480-485,共6页
提出一种基于PC图形卡W Buffer的交互光线投射算法,这是一种面绘制与体绘制结合的快速体绘制方法.首先用3D分割等方法提取边界体素或用MarchingCubes等算法提取等值面,然后利用图形硬件预先投影这些边界体素或等值面以产生深度信息,最... 提出一种基于PC图形卡W Buffer的交互光线投射算法,这是一种面绘制与体绘制结合的快速体绘制方法.首先用3D分割等方法提取边界体素或用MarchingCubes等算法提取等值面,然后利用图形硬件预先投影这些边界体素或等值面以产生深度信息,最后由光线投射模块根据W Buffer中的深度信息快速找到实际等值面的位置,进行采样、着色、不透明度与颜色合成等渲染工作.这一方法不仅显著地加快了成像速度,而且不降低图像质量.实验结果表明,用该算法在PC机上以200×200分辨率渲染时,能达到10帧/秒的速度,基本满足虚拟内窥镜系统的动态导航和高质量图像要求,具有较大实用价值. 展开更多
关键词 虚拟内窥镜 光线投射 交互体绘制 W—buffer PC图形卡
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