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Objective assessment of the effect of pupil size upon the power distribution of multifocal contact lenses 被引量:2
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作者 Eleni Papadatou Antonio J.Del Aguila-Carrasco +2 位作者 Jose J.Esteve-Taboada David Madrid-Costa Alejandro Cervino-Exposito 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第1期103-108,共6页
● AIM: To analytically assess the effect of pupil size upon the refractive power distributions of different designs of multifocal contact lenses.● METHODS: Two multifocal contact lenses of center-near design and one... ● AIM: To analytically assess the effect of pupil size upon the refractive power distributions of different designs of multifocal contact lenses.● METHODS: Two multifocal contact lenses of center-near design and one multifocal contact lens of center-distance design were used in this study. Their power profiles were measured using the NIMO TR1504 device(LAMBDA-X, Belgium). Based on their power profiles, the power distribution was assessed as a function of pupil size. For the high addition lenses, the resulting refractive power as a function of viewing distance(far, intermediate, and near) and pupil size was also analyzed.● RESULTS: The power distribution of the lenses was affected by pupil size differently. One of the lenses showed a significant spread in refractive power distribution, from about-3 D to 0 D. Generally, the power distribution of the lenses expanded as the pupil diameter became greater. The surface of the lens dedicated for each distance varied substantially with the design of the lens.● CONCLUSION: In an experimental basis, our results show how the lenses power distribution is affected by the pupil size and underlined the necessity of careful evaluation of the patient's visual needs and the optical properties of a multifocal contact lens for achieving the optimal visual outcome. 展开更多
关键词 multifocal 隐形眼镜 学生尺寸 驱动侧面 折射力量分发
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Ocular higher-order aberrations and mesopic pupil size in individuals screened for refractive surgery 被引量:2
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作者 Seyed Javad Hashemian Mohammad Soleimani +4 位作者 Alireza Foroutan Mahmood Joshaghani Mohammad Jafar Ghaempanah Mohammad Ebrahim Jafari Mehdi Yaseri 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第2期222-225,共4页
AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. · METHODS: Ocular HOAs and mesopic pupil size were studied in 2 458 e... AIM: To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. · METHODS: Ocular HOAs and mesopic pupil size were studied in 2 458 eyes of 1 240 patients with myopia, myopic astigmatism and compound myopic astigmatism and 215 eyes of 110 patients with hyperopia, hyperopic astigmatism and compound hyperopic astigmatism using the Zywave aberrometer (Busch& Lomb). All patients had correctable refractive errors without a history of refractive surgery or underlying diseases. Root-mean-square values of HOAs, total spherical aberration, total coma and mesopic pupil size were analyzed. Ocular HOAs were measured across a ≥ 6.0 mm pupil, and pupil size measurements were performed under the mesopic condition. · RESULTS: The mean values of HOAs, total spherical aberration and total coma in the myopic group were 0.369 μm, ±0.233, 0.133±0.112μm and 0.330±0.188μm, respectively. In the hyperopic group the mean values of HOAs, total spherical aberration and total coma were 0.418μm±0.214, 0.202±0.209μm and 0.343±0.201μm, respectively. Hyperopes showed greater total HOAs (P <0.01) and total spherical aberration (P <0.01) compared to myopes. In age-matched analysis, only the amount of total spherical aberration was higher in the hyperopic group (P =0.05). Mesopic pupil size in the myopic group was larger (P ≤0.05). · CONCLUSION: The results suggested that significant levels of HOAs were found in both groups which are important for planning refractive surgeries on Iranians. There were significantly higher levels of total spherical aberration in hyperopes compared to myopes. Mesopic pupil size was larger in myopic group. 展开更多
关键词 corneal WAVEFRONT ABERRATION pupil mesopic vision race MYOPIA HYPEROPIA
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Photopic pupil size change in myopic orthokeratology and its influence on axial length elongation 被引量:2
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作者 Meng-Jun Zhu Li Ding +4 位作者 Lin-Lin Du Jun Chen Xian-Gui He Shan-Shan Li Hai-Dong Zou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第8期1322-1330,共9页
AIM:To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology(ortho-k)over 1-year period and its effects on the axial elongation.METHODS:A total of 202 Chinese myopic children... AIM:To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology(ortho-k)over 1-year period and its effects on the axial elongation.METHODS:A total of 202 Chinese myopic children were enrolled in this prospective clinical trial.Ninetyfive subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study.Axial length(AL)was measured before enrollment and every 6mo after the start of ortho-k.The photopic pupil diameter(PPD)was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx.Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation.RESULTS:Compared with spectacle group,the average 1-year axial elongation was significantly slower in the ortho-k group(0.25±0.27 vs 0.44±0.23 mm,P<0.0001).In ortho-k group,PPDs significantly decreased from 4.21±0.62 mm to 3.94±0.53 mm after 1mo of lens wear(P=0.001,Bonferroni correction)and the change lasts for 3-month visit.No significantly change during the other follow-up visits was found(P>0.05,Bonferroni correction).The 4.81 mm PPD may be a possible cutoff point in the ortho-k group.Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period(t=-3.09,P=0.003).In ortho-k group,univariate analyses indicated that those with older age,greater degree of myopia,longer AL,smaller baseline PPD(PPDbaseline)experienced a smaller change in AL.In multivariate analyses,older age,greater AL and smaller PPDbaseline were associated with smaller increases in AL.In spectacle group,PPD tended to be stable(P>0.05,Bonferroni correction)and did not affect axial growth.CONCLUSION:PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment.Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k. 展开更多
关键词 ORTHOKERATOLOGY MYOPIA axial length pupil diameter ACCOMMODATION
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Pupil Size Measurement and Sucrose Ingestion for Quantifying and Decreasing Burden of Women during Mammography 被引量:1
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作者 Yongbum Lee Mieko Uchiyama Tomoko Sumiyoshi 《Journal of Biomedical Science and Engineering》 2015年第10期700-706,共7页
Many women feel a physical burden, which usually appears as a pain, during mammography. We examined the pain-related pupil dilation response during mammography. Twenty-four healthy women participated in the examinatio... Many women feel a physical burden, which usually appears as a pain, during mammography. We examined the pain-related pupil dilation response during mammography. Twenty-four healthy women participated in the examination. They were randomly assigned to water group or sucrose group. Water group and sucrose group ingested distilled water and a sucrose solution during mammography, respectively. Their pupil sizes were measured during mammography excluding X-ray irradiation. The subjective intensity of pain during mammography was also assessed using visual analogue scales (VAS). The mean pupil diameter was 2.99 mm in relaxation phase before mammography, while it was 3.15 mm in a few seconds after breast compression (pressure phase). The difference between the two was statistically significant (p p < 0.01). These results suggest that we may be able to assess objectively the degree of pain associated with mammography and sweet taste stimuli may be effective to alleviate a women’s burden received during mammography. 展开更多
关键词 MAMMOGRAPHY PAIN Assessment PAIN Alleviation pupil DILATION Sweet Stimuli
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Robust Facial Biometric Authentication System Using Pupillary Light Reflex for Liveness Detection of Facial Images
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作者 Puja S.Prasad Adepu Sree Lakshmi +5 位作者 Sandeep Kautish Simar Preet Singh Rajesh Kumar Shrivastava Abdulaziz S.Almazyad Hossam M.Zawbaa Ali Wagdy Mohamed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期725-739,共15页
Pupil dynamics are the important characteristics of face spoofing detection.The face recognition system is one of the most used biometrics for authenticating individual identity.The main threats to the facial recognit... Pupil dynamics are the important characteristics of face spoofing detection.The face recognition system is one of the most used biometrics for authenticating individual identity.The main threats to the facial recognition system are different types of presentation attacks like print attacks,3D mask attacks,replay attacks,etc.The proposed model uses pupil characteristics for liveness detection during the authentication process.The pupillary light reflex is an involuntary reaction controlling the pupil’s diameter at different light intensities.The proposed framework consists of two-phase methodologies.In the first phase,the pupil’s diameter is calculated by applying stimulus(light)in one eye of the subject and calculating the constriction of the pupil size on both eyes in different video frames.The above measurement is converted into feature space using Kohn and Clynes model-defined parameters.The Support Vector Machine is used to classify legitimate subjects when the diameter change is normal(or when the eye is alive)or illegitimate subjects when there is no change or abnormal oscillations of pupil behavior due to the presence of printed photograph,video,or 3D mask of the subject in front of the camera.In the second phase,we perform the facial recognition process.Scale-invariant feature transform(SIFT)is used to find the features from the facial images,with each feature having a size of a 128-dimensional vector.These features are scale,rotation,and orientation invariant and are used for recognizing facial images.The brute force matching algorithm is used for matching features of two different images.The threshold value we considered is 0.08 for good matches.To analyze the performance of the framework,we tested our model in two Face antispoofing datasets named Replay attack datasets and CASIA-SURF datasets,which were used because they contain the videos of the subjects in each sample having three modalities(RGB,IR,Depth).The CASIA-SURF datasets showed an 89.9%Equal Error Rate,while the Replay Attack datasets showed a 92.1%Equal Error Rate. 展开更多
关键词 SIFT pupil CASIA-SURF pupillary light reflex replay attack dataset brute force
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New complex physiological findings evolve hypothesized mechanisms of Dravet syndrome
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作者 MacKenzie A.Howard 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1867-1868,共2页
Developmental and epileptic encephalopathies(DEEs)are neurological disorders generally involving medically intractable seizures and a diverse array of comorbid neuropsychiatric delays and deficits that may severely af... Developmental and epileptic encephalopathies(DEEs)are neurological disorders generally involving medically intractable seizures and a diverse array of comorbid neuropsychiatric delays and deficits that may severely affect cognition,mood,sleep,social behavior,movement control,learning,and/or memory.Dravet syndrome(DS),also known as Severe Myoclonic Epilepsy of Infancy. 展开更多
关键词 sized finding seizures
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Population size estimates based on GPS telemetry
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作者 Yu-Xuan Fan Pu-Zheng Xie +5 位作者 Chi Ma Ting Chen Xiao Ye Hua-Lin Xu Qiong Yang Peng-Fei Fan 《Zoological Research》 SCIE CSCD 2024年第1期36-38,共3页
DEAR EDITOR,Accurate estimation of population size is a crucial issue in wildlife population ecology and conservation.While Global Positioning System(GPS)collars are well recognized as an effective method for monitori... DEAR EDITOR,Accurate estimation of population size is a crucial issue in wildlife population ecology and conservation.While Global Positioning System(GPS)collars are well recognized as an effective method for monitoring wildlife behavior,their application in direct wildlife population size estimation remains underutilized.In this study,GPS telemetry was employed to survey a rhesus macaque(Macaca mulatta)population on Neilingding Island in Guangdong,China.From May 2021 to April 2022,32 macaques across nine groups were fitted with GPS collars,producing a dataset of 109739 location fixes.Analyzing data from all tracked individuals revealed the annual home ranges of the nine groups. 展开更多
关键词 China ISLAND size
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High-Volume Mineral Admixtures Cement: The Effects of Particle Size Distribution
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作者 黄启珉 WANG Kun +3 位作者 LU Jiping YU Jianping SHENG Zhenhua 杨露 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期102-108,共7页
The effects of high-volume slag-fly ash cement with different particle sizes on hydration degree,microstructure and mechanical properties were systematically studied,by means of laser particle size(DLS),X-ray diffract... The effects of high-volume slag-fly ash cement with different particle sizes on hydration degree,microstructure and mechanical properties were systematically studied,by means of laser particle size(DLS),X-ray diffraction (XRD),comprehensive thermal analysis (TG-DTA),scanning electron microscopy(SEM) and mechanical properties tests.The results show that suitable particle size distribution of cementitious material has significantly promoting effects on hydration reaction rate and mechanical properties.Compared with slag without further grinding,the slag after ball milling for 4 h has an obvious improvement in reactivity,which also provides a faster hydration rate and higher compressive strength for the cementitious material.When the slag milled for 1 and 4 h is mixed at a mass ratio of 2:1 (i e,slag with D_(50) of 7.4μm and average size of 9.9μm,and slag with D_(50) value of 2.6μm and average size of 5.3μm),and a certain amount of fly ash is added in,the most obvious improvement of compressive strength of cement is achieved. 展开更多
关键词 ultrafine slag MICROSTRUCTURE compressive strength particle size
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Tumor size discrepancy between endoscopic and pathological evaluations in colorectal endoscopic submucosal dissection
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作者 Takeshi Onda Osamu Goto +11 位作者 Toshiaki Otsuka Yoshiaki Hayasaka Shun Nakagome Tsugumi Habu Yumiko Ishikawa Kumiko Kirita Eriko Koizumi Hiroto Noda Kazutoshi Higuchi Jun Omori Naohiko Akimoto Katsuhiko Iwakiri 《World Journal of Gastrointestinal Endoscopy》 2024年第3期136-147,共12页
BACKGROUND Tumor size impacts the technical difficulty and histological curability of colorectal endoscopic submucosal dissection(ESD);however,the preoperative evaluation of tumor size is often different from histolog... BACKGROUND Tumor size impacts the technical difficulty and histological curability of colorectal endoscopic submucosal dissection(ESD);however,the preoperative evaluation of tumor size is often different from histological assessment.Analyzing influential factors on failure to obtain an accurate tumor size evaluation could help prepare optimal conditions for safer and more reliable ESD.METHODS This was a retrospective study conducted at a single institution.A total of 377 lesions removed by colorectal ESD at our hospital between April 2018 and March 2022 were collected.We first assessed the difference in size with an absolute per-centage of the scaling discrepancy.Subsequently,we compared the clinicopatho-logical characteristics of the correct scaling group(>-33%and<33%)with that of the incorrect scaling group(<-33%or>33%),which was further subdivided into the underscaling group(-33%or less of the discrepancy)and overscaling group(33%or more of the discrepancy),respectively.As secondary outcome measures,parameters on size estimation were compared between the underscaling and correct scaling groups,as well as between the overscaling and correct scaling groups.Finally,multivariate analysis was performed in terms of the following relevant parameters on size estimation:Pathological size,location,and possible influential factors(P<0.1)in the univariate analysis.RESULTS The mean of absolute percentage in the scaling discordance was 21%,and 91 lesions were considered to be incorrectly estimated in size.The incorrect scaling was significantly remarkable in larger lesions(40 mm vs 28 mm;P<0.001)and less experience(P<0.001),and these two factors were influential on the underscaling(75 lesions;P<0.001).Conversely,compared with the correct scaling group,16 lesions in the overscaling group were significantly small(20 mm vs 28 mm;P<0.001),and the small lesion size was influential on the overscaling(P=0.002).CONCLUSION Lesions indicated for colorectal ESD tended to be underestimated in large tumors,but overestimated in small ones.This discrepancy appears worth understanding for optimal procedural preparation. 展开更多
关键词 Endoscopic submucosal dissection Colorectal tumor Tumor size size estimation size discrepancy
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Natural variation of an autophagy-family gene among rice subspecies affects grain size and weight
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作者 Shiying Huang Peng Wang +10 位作者 Caijing Li Qingwen Zhou Tao Huang Yicong Cai Qin Cheng Hui Wang Qi Zhong Zhihao Chen Liping Chen Haohua He Jianmin Bian 《The Crop Journal》 SCIE CSCD 2024年第1期121-132,共12页
Elucidating the genetic basis of natural variation in grain size and weight among rice varieties can help breeders develop high-yielding varieties.We identified a novel gene,GW3a(Grain Weight 3a)(LOC_Os03g27350),that ... Elucidating the genetic basis of natural variation in grain size and weight among rice varieties can help breeders develop high-yielding varieties.We identified a novel gene,GW3a(Grain Weight 3a)(LOC_Os03g27350),that affects rice grain size and weight.gw3a mutants showed higher total starch content and dry matter accumulation than the wild type(WT),Nipponbare,suggesting that GW3a negatively regulates grain size and weight.Moreover,our study found that GW3a interacted with OsATG8 by cleaving it,suggesting that GW3a may be involved in the assembly of autophagosomes and starch degradation in plants.The haplotype analysis of GW3a showed functional differences between indica and japonica rice.Taken together,we conclude that GW3a is expressed in the autophagosome pathway regulating starch metabolism in rice,affecting yield-related traits,such as grain size,grain weight and thousand grain weight(TGW).Our findings also shed new light on autophagy-mediated yield trait regulation,proposing a possible strategy for the genetic improvement of high-yield germplasm in rice. 展开更多
关键词 Grain size GW3a AUTOPHAGY Starch content
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Spatial patterns of zooplankton abundance,biovolume,and size structure in response to environmental variables:a case study in the Yellow Sea and East China Sea
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作者 Song SUN Haochen XIAN +2 位作者 Xiaoxia SUN Mingliang ZHU Mengtan LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期113-127,共15页
The Yellow Sea(YS)and East China Sea(ECS)are highly dynamic marginal seas of the northwestern Pacific Ocean.To gain an in-depth understanding of zooplankton community structure,zooplankton abundance,biovolume,and size... The Yellow Sea(YS)and East China Sea(ECS)are highly dynamic marginal seas of the northwestern Pacific Ocean.To gain an in-depth understanding of zooplankton community structure,zooplankton abundance,biovolume,and size structure in summer 2017 in the YS and ECS were assessed using ZooScan imaging analysis.Zooplankton abundance and biovolume ranged 2.94–1187.14 inds./m^(3)and 3.13–3438.51 mm^(3)/m^(3),respectively.Based on the biovolume data of the categorized size classes of 26 identified taxonomic groups,the zooplankton community was classified into five groups,and each group was coupled with distinctive oceanographic features.Under the influence of the Yellow Sea Cold Water Mass,the Yellow Sea offshore group featured the lowest bottom temperature(10.84±3.42℃)and the most abundant Calanoids(mainly in the 2–3 mm size class).In the Yellow Sea inshore group,Hydrozoans showed the largest biovolume and dominated in the 3–4-mm and>5-mm size classes.The East China Sea offshore group,which was affected by the Kuroshio Branch Current,featured high temperature and salinity,and the lowest bottom dissolved oxygen(2.58±0.5 mg/L).The lowest values of zooplankton abundance and biovolume in the East China Sea offshore group might be attributed to the bottom dissolved oxygen contents.The East China Sea inshore group,which was mainly influenced by the Zhejiang-Fujian Coastal Current and Changjiang Diluted Water,was characterized by high chlorophyll a and the largest biovolume of carnivorous Siphonophores(280.82±303.37 mm^(3)/m^(3)).The Changjiang River estuary offshore group showed the most abundant Cyclopoids,which might be associated with the less turbid water mass in this region.Seawater temperature was considered the most important factor in shaping the size compositions of Calanoids in different groups. 展开更多
关键词 ZOOPLANKTON size structure ZooScan Yellow Sea East China Sea
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Effect of grain size on gas bubble evolution in nuclear fuel:Phase-field investigations
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作者 孙丹 杨青峰 +7 位作者 赵家珺 高士鑫 辛勇 周毅 尹春雨 陈平 赵纪军 王园园 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期563-572,共10页
Numerous irradiation-induced gas bubbles are created in the nuclear fuel during irradiation, leading to the change of microstructure and the degradation of mechanical and thermal properties. The grain size of fuel is ... Numerous irradiation-induced gas bubbles are created in the nuclear fuel during irradiation, leading to the change of microstructure and the degradation of mechanical and thermal properties. The grain size of fuel is one of the important factors affecting bubble evolution. In current study, we first predict the thermodynamic behaviors of point defects as well as the interplay between vacancy and gas atom in both UO_(2) and U_(3)Si_(2) according to ab initio approach. Then, we establish the irradiation-induced bubble phase-field model to investigate the formation and evolution of intra-and inter-granular gas bubbles. The effects of fission rate and temperature on the evolutions of bubble morphologies in UO_(2) and U_(3)Si_(2) have been revealed. Especially, a comparison of porosities under different grain sizes is examined and analyzed. To understand the thermal conductivity as functions of grain size and porosity, the heat transfer capability of U_(3)Si_(2) is evaluated. 展开更多
关键词 grain size point defects fission gas bubble
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Boosting kinetic separation of ethylene and ethane on microporous materials via crystal size control
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作者 Yixuan Ma Cong Yu +5 位作者 Lifeng Yang Rimin You Yawen Bo Qihan Gong Huabin Xing Xili Cui 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期85-91,共7页
The adsorptive separation of C_(2)H_(4)and C_(2)H_(6),as an alternative to distillation units consuming high energy,is a promising yet challenging research.The great similarity in the molecular size of C_(2)H_(4)and C... The adsorptive separation of C_(2)H_(4)and C_(2)H_(6),as an alternative to distillation units consuming high energy,is a promising yet challenging research.The great similarity in the molecular size of C_(2)H_(4)and C_(2)H_(6)brings challenges to the regulation of adsorbents to realize efficient dynamic separation.Herein,we reported the enhancement of the kinetic separation of C_(2)H_(4)/C_(2)H_(6)by controlling the crystal size of ZnAtzPO_(4)(Atz=3-amino-1,2,4-triazole)to amplify the diffusion difference of C_(2)H_(4)and C_(2)H_(6).Through adjusting the synthesis temperature,reactant concentration,and ligands/metal ions molar ratio,ZnAtzPO4 crystals with different sizes were obtained.Both single-component kinetic adsorption tests and binary-component dynamic breakthrough experiments confirmed the enhancement of the dynamic separation of C_(2)H_(4)/C_(2)H_(6)with the increase in the crystal size of ZnAtzPO_(4).The separation selectivity of C_(2)H_(4)/C_(2)H_(6)increased from 1.3 to 98.5 with the increase in the crystal size of ZnAtzPO_(4).This work demonstrated the role of morphology and size control of adsorbent crystals in the improvement of the C_(2)H_(4)/C_(2)H_(6)kinetic separation performance. 展开更多
关键词 ADSORPTION ADSORBENT ETHYLENE Binary mixture Crystal size control Kinetic separation
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Effect of Size Change on Mechanical Properties of Monolayer Arsenene
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作者 郭娟 刘贵立 孙震宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期206-212,共7页
The Young's modulus, shear modulus and Poisson's ratio of monolayer arsenene with different sizes were calculated by finite element method, so as to explore the influence of dimension and orientation on the me... The Young's modulus, shear modulus and Poisson's ratio of monolayer arsenene with different sizes were calculated by finite element method, so as to explore the influence of dimension and orientation on the mechanical properties of monolayer arsenene. The calculation results show that the small size has a significant effect on the mechanical properties of the monolayer arsenene. The smaller the size, the larger the Young's modulus and Poisson's ratio of the monolayer arsenene. The size change has a great influence on the Young's modulus of the arsenene handrail direction, and the Young's modulus of the zigzag direction is not sensitive to the size change. Similarly, the size change has a significant effect on the shear modulus of arsenene in the handrail direction, while the shear modulus in the zigzag direction has no significant effect on its size change. For the Poisson's ratio, the situation is just the opposite, and the effect of the size change on the Poisson's ratio of the arsenene zigzag direction is greater than that of the handrail direction. 展开更多
关键词 finite element method arsenene size change mechanical properties
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Efficient Electromagnetic Wave Absorption and Thermal Infrared Stealth in PVTMS@MWCNT Nano‑Aerogel via Abundant Nano‑Sized Cavities and Attenuation Interfaces
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作者 Haoyu Ma Maryam Fashandi +5 位作者 Zeineb Ben Rejeb Xin Ming Yingjun Liu Pengjian Gong Guangxian Li Chul B.Park 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期370-383,共14页
Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT... Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work. 展开更多
关键词 Nano-pore size Heterogeneous interface Electromagnetic wave absorption Thermal infrared stealth Nano-aerogel
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A data-driven model of drop size prediction based on artificial neural networks using small-scale data sets
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作者 Bo Wang Han Zhou +3 位作者 Shan Jing Qiang Zheng Wenjie Lan Shaowei Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期71-83,共13页
An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data sets.After training,the deviation between calculate and experimental results are 3.8%and ... An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data sets.After training,the deviation between calculate and experimental results are 3.8%and 9.3%,respectively.Through ANN model,the influence of interfacial tension and pulsation intensity on the droplet diameter has been developed.Droplet size gradually increases with the increase of interfacial tension,and decreases with the increase of pulse intensity.It can be seen that the accuracy of ANN model in predicting droplet size outside the training set range is reach the same level as the accuracy of correlation obtained based on experiments within this range.For two kinds of columns,the drop size prediction deviations of ANN model are 9.6%and 18.5%and the deviations in correlations are 11%and 15%. 展开更多
关键词 Artificial neural network Drop size Solvent extraction Pulsed column Two-phase flow HYDRODYNAMICS
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The clutch size,incubation behavior of Reeves’s Pheasant(Syrmaticus reevesii) and their responses to ambient temperature and precipitation
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作者 Ting Jin Shuai Lu +7 位作者 Yunqi Wang Junqin Hua Zhengxiao Liu Qian Hu Yating Liu Yuze Zhao Jianqiang Li Jiliang Xu 《Avian Research》 SCIE CSCD 2024年第1期72-80,共9页
Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conserv... Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conservation.Reeves’ s Pheasant(Syrmaticus reevesii) is a threatened species endemic to China,which is characterized by female-only incubation.However,there is a lack of information regarding the impact of weather conditions on clutch size and incubation behavior in this species.Using satellite tracking,we tracked 27 wild female Reeves’ s Pheasants from 2020 to 2023 in Hubei Province,China.We explored their clutch size and incubation behavior,as well as their responses to ambient temperature and precipitation.Clutch size averaged 7.75 ±1.36,had an association with average ambient temperature and average daily precipitation during the egglaying period,and was potentially linked to female breeding attempts.Throughout the incubation period,females took an average of 0.73 ±0.46 recesses every 24 h,with an average recess duration of 100.80 ±73.37 min and an average nest attendance of 92.98 ±5.27%.They showed a unimodal recess pattern in which nest departures peaked primarily between 13:00 and 16:00.Furthermore,females rarely left nests when daily precipitation was high.Recess duration and nest attendance were influenced by the interaction between daily mean ambient temperature and daily precipitation,as well as day of incubation.Additionally,there was a positive correlation between clutch size and recess duration.These results contribute valuable insights into the lifehistory features of this endangered species. 展开更多
关键词 Ambient temperature Clutch size Incubation behavior PRECIPITATION Reeves’s Pheasant
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240 nm AlGaN-based deep ultraviolet micro-LEDs:size effect versus edge effect
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作者 Shunpeng Lu Jiangxiao Bai +6 位作者 Hongbo Li Ke Jiang Jianwei Ben Shanli Zhang Zi-Hui Zhang Xiaojuan Sun Dabing Li 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期55-62,共8页
240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge ef... 240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs. 展开更多
关键词 ALGAN deep ultraviolet micro-LEDs light extraction efficiency size effect edge effect
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Experimental study on the size effect on the equation of state of concretes under shock loading
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作者 Mei Li Jian Cui +2 位作者 Yanchao Shi Baijian Tang Xin Chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期160-167,共8页
Adopting the classical theory of hydrocodes,the constitutive relations of concretes are separated into an equation of state(EoS)which describes the volumetric behavior of concrete material and a strength model which d... Adopting the classical theory of hydrocodes,the constitutive relations of concretes are separated into an equation of state(EoS)which describes the volumetric behavior of concrete material and a strength model which depicts the shear properties of concrete.The experiments on the EoS of concrete is always challenging due to the technical difficulties and equipment limitations,especially for the specimen size effect on the EoS.Although some researchers investigate the shock properties of concretes by fly-plate impact tests,the specimens used in their tests are usually in one size.In this paper,the fly-plate impact tests on concrete specimens with different sizes are performed to investigate the size effect on the shock properties of concrete materials.The mechanical background of the size effect on the shock properties are revealed,which is related to the lateral rarefaction effect and the deviatoric stress produced in the specimen.According to the tests results,the modified EoS considering the size effect on the shock properties of concrete are proposed,which the bulk modulus of concrete is unpredicted by up to 20% if size effects are not accounted for. 展开更多
关键词 CONCRETE Equation of state size effect Shock wave Fly-plate impact test
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Rice AGL1 determines grain size and sterile lemma identity
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作者 Haiping Yu An Wang +4 位作者 Guangheng Zhang Guojun Dong Longbiao Guo Qian Qian Deyong Ren 《The Crop Journal》 SCIE CSCD 2024年第2期630-634,共5页
The grass spikelet is a unique inflorescence structure that determines grain size.Although many genetic factors have been well characterized for grain size and glume development,the underlying molecular mechanisms in ... The grass spikelet is a unique inflorescence structure that determines grain size.Although many genetic factors have been well characterized for grain size and glume development,the underlying molecular mechanisms in rice are far from established.Here,we isolated rice gene,AGL1 that controlled grain size and determines the fate of the sterile lemma.Loss of function of AGL1 produced larger grains and reduced the size of the sterile lemma.Larger grains in the agl1 mutant were caused by a larger number of cells that were longer and wider than in the wild type.The sterile lemma in the mutant spikelet was converted to a rudimentary glume-like organ.Our findings showed that the AGL1(also named LAX1)protein positively regulated G1 expression,and negatively regulated NSG1 expression,thereby affecting the fate of the sterile lemma.Taken together,our results revealed that AGL1 played a key role in negative regulation of grain size by controlling cell proliferation and expansion,and supported the opinion that rudimentary glume and sterile lemma in rice are homologous organs. 展开更多
关键词 Abnormal grain and sterile lemma 1 Oryza sativa Grain size Rudimentary glume
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