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金属无机复合抑制剂强化分离白钨矿与方解石
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作者 赵冠飞 冯博 +5 位作者 朱冬梅 邱仙辉 高志勇 严华山 赖瑞森 邱廷省 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第2期643-654,共12页
研究由硫酸铝和水玻璃硅酸钠(AlSS)组成的金属无机复合抑制剂对白钨矿与方解石浮选分离的影响。Zeta电位和吸附量测定结果表明,由Al(OH)_(4)^(−)和SiO_(m)(OH)_(n)^(4−2m−n)组成的负电荷胶体颗粒倾向于吸附在方解石表面,抑制油酸钠(NaOL... 研究由硫酸铝和水玻璃硅酸钠(AlSS)组成的金属无机复合抑制剂对白钨矿与方解石浮选分离的影响。Zeta电位和吸附量测定结果表明,由Al(OH)_(4)^(−)和SiO_(m)(OH)_(n)^(4−2m−n)组成的负电荷胶体颗粒倾向于吸附在方解石表面,抑制油酸钠(NaOL)的吸附,而负电荷胶体颗粒在白钨矿表面的吸附量较低,导致NaOL在白钨矿表面的吸附量较大。接触角测量结果表明,白钨矿在NaOL+AlSS溶液中的疏水性明显优于方解石。XPS测试结果表明,Al和Si在方解石表面有吸附,而在白钨矿表面没有吸附。与只添加水玻璃(硅酸钠,SS)相比,AlSS对方解石的抑制作用明显增强,对白钨矿浮选几乎没有影响。在白钨矿与方解石混合矿中添加AlSS,可获得WO_(3)品位为68.34%、WO_(3)回收率为83.14%的白钨矿精矿。 展开更多
关键词 白钨矿 方解石 分离强化 油酸钠 金属无机复合抑制剂
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Genetic dissection and validation of a major QTL for grain weight on chromosome 3B in bread wheat(Triticum aestivum L.) 被引量:2
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作者 Simin Liao Zhibin Xu +7 位作者 Xiaoli Fan Qiang Zhou Xiaofeng Liu Cheng Jiang Liangen Chen Dian Lin bo feng Tao Wang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期77-92,共16页
Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(... Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(RIL)population derived from a cross between W7268 and Chuanyu 12(CY12)was employed to detect quantitative trait loci(QTLs)for thousand-grain weight(TGW),grain length(GL),grain width(GW),and the ratio of grain length to width(GLW)in six environments.Seven major QTLs,QGl.cib-2D,QGw.cib-2D,QGw.cib-3B,QGw.cib-4B.1,QGlw.cib-2D.1,QTgw.cib-2D.1 and QTgw.cib-3B.1,were consistently identified in at least four environments and the best linear unbiased estimation(BLUE)datasets,and they explained 2.61 to 34.85%of the phenotypic variance.Significant interactions were detected between the two major TGW QTLs and three major GW loci.In addition,QTgw.cib-3B.1 and QGw.cib-3B were co-located,and the improved TGW at this locus was contributed by GW.Unlike other loci,QTgw.cib-3B.1/QGw.cib-3B had no effect on grain number per spike(GNS).They were further validated in advanced lines using Kompetitive Allele Specific PCR(KASP)markers,and a comparison analysis indicated that QTgw.cib-3B.1/QGw.cib-3B is likely a novel locus.Six haplotypes were identified in the region of this QTL and their distribution frequencies varied between the landraces and cultivars.According to gene annotation,spatial expression patterns,ortholog analysis and sequence variation,the candidate gene of QTgw.cib-3B.1/QGw.cib-3B was predicted.Collectively,the major QTLs and KASP markers reported here provide valuable information for elucidating the genetic architecture of grain weight and for molecular marker-assisted breeding in grain yield improvement. 展开更多
关键词 thousand-grain weight QTL mapping haplotype analysis candidate gene
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Diamond-based electron emission:Structure,properties and mechanisms
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作者 Liang-Xue Gu Kai Yang +10 位作者 Yan Teng Wei-Kang Zhao Geng-You Zhao Kang-Kang Fan bo feng Rong Zhang You-Dou Zheng Jian-Dong Ye Shun-Ming Zhu Kun Tang Shu-Lin Gu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期165-177,共13页
Diamond has an ultrawide bandgap with excellent physical properties,such as high critical electric field,excellent thermal conductivity,high carrier mobility,etc.Diamond with a hydrogen-terminated(H-terminated)surface... Diamond has an ultrawide bandgap with excellent physical properties,such as high critical electric field,excellent thermal conductivity,high carrier mobility,etc.Diamond with a hydrogen-terminated(H-terminated)surface has a negative electron affinity(NEA)and can easily produce surface electrons from valence or trapped electrons via optical absorption,thermal heating energy or carrier transport in a PN junction.The NEA of the H-terminated surface enables surface electrons to emit with high efficiency into the vacuum without encountering additional barriers and promotes further development and application of diamond-based emitting devices.This article reviews the electron emission properties of H-terminated diamond surfaces exhibiting NEA characteristics.The electron emission is induced by different physical mechanisms.Recent advancements in electron-emitting devices based on diamond are also summarized.Finally,the current challenges and future development opportunities are discussed to further develop the relevant applications of diamond-based electronemitting devices. 展开更多
关键词 DIAMOND negative ELECTRON AFFINITY (NEA) PN JUNCTION ELECTRON emission
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Near-zero-adhesion-enabled intact wafer-scale resist-transfer printing for high-fidelity nanofabrication on arbitrary substrates
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作者 Zhiwen Shu bo feng +5 位作者 Peng Liu Lei Chen Huikang Liang Yiqin Chen Jianwu Yu Huigao Duan 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期313-326,共14页
There is an urgent need for novel processes that can integrate different functional nanostructures onto specific substrates,so as to meet the fast-growing need for broad applications in nanoelectronics,nanophotonics,a... There is an urgent need for novel processes that can integrate different functional nanostructures onto specific substrates,so as to meet the fast-growing need for broad applications in nanoelectronics,nanophotonics,and fexible optoelectronics.Existing direct-lithography methods are difficult to use on fexible,nonplanar,and biocompatible surfaces.Therefore,this fabrication is usually accomplished by nanotransfer printing.However,large-scale integration of multiscale nanostructures with unconventional substrates remains challenging because fabrication yields and quality are often limited by the resolution,uniformity,adhesivity,and integrity of the nanostructures formed by direct transfer.Here,we proposed a resist-based transfer strategy enabled by near-zero adhesion,which was achieved by molecular modification to attain a critical surface energy interval.This approach enabled the intact transfer of wafer-scale,ultrathin-resist nanofilms onto arbitrary substrates with mitigated cracking and wrinkling,thereby facilitating the in situ fabrication of nanostructures for functional devices.Applying this approach,fabrication of three-dimensional-stacked multilayer structures with enhanced functionalities,nanoplasmonic structures with~10 nm resolution,and MoS2-based devices with excellent performance was demonstrated on specific substrates.These results collectively demonstrated the high stability,reliability,and throughput of our strategy for optical and electronic device applications. 展开更多
关键词 resist-based transfer printing near-zero adhesion critical surface energy wafer-scale nanofabrication in situ fabrication optoelectronic devices
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Endowing low fatigue for elastocaloric effect by refined hierarchical microcomposite in additive manufactured NiTiCuCo alloy
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作者 bo feng Helong Liu +6 位作者 Ying Yang Hui Shen Yang Ren Yinong Liu Lishan Cui Bingmin Huang Shijie Hao 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期307-322,共16页
NiTiCu-based shape memory alloys have been considered as ideal materials for solid-state refrigeration due to their superb cycling stability for elastocaloric effect.However,the embrittlement and deterioration caused ... NiTiCu-based shape memory alloys have been considered as ideal materials for solid-state refrigeration due to their superb cycling stability for elastocaloric effect.However,the embrittlement and deterioration caused by secondary phase and coarse grains restrict their applications,and it is still challenging since the geometric components are required.Here,bulk NiTiCuCo parts with excellent forming quality were fabricated by laser powder bed fusion(LPBF)technique.The as-fabricated alloy exhibits refined three-phases hierarchical microcomposite formed based on the rapid cooling mode of LPBF,composed of intricate dendritic Ti2Ni–NiTi composite and nano Ti2Cu embedded inside the NiTi-matrix.This configuration endows far superior elastocaloric stability compared to the as-cast counterpart.The low fatigue stems from the strong elastic coupling between the interphases with reversible martensite transformation,revealed by in-situ synchrotron high-energy x-ray diffraction.The fabrication of NiTiCuCo alloy via LPBF fills the bill of complex geometric structures for elastocaloric NiTiCu alloys.The understanding of interphase micro-coupling could provide the guide for designing LPBF fabricated shape memory-based composites,enabling their applications for special demands on other functionalities. 展开更多
关键词 NiTiCuCo shape memoryalloy microcomposite high-energyx-raydiffraction laser powderbedfusion
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Effect of capsule treatment on visual acuity and quality after phacoemulsification lens implantation in myopic patients with cataract
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作者 Wei Liu Qi Liu +2 位作者 Fang Zhou bo feng Wan-Ling Wu 《World Journal of Clinical Cases》 SCIE 2024年第19期3882-3889,共8页
BACKGROUND Cataracts pose a significant clinical burden due to their complex pathogenesis.In recent years,an increase in cataracts coexisting with myopia has heightened the incidence of retinopathy and posterior vitre... BACKGROUND Cataracts pose a significant clinical burden due to their complex pathogenesis.In recent years,an increase in cataracts coexisting with myopia has heightened the incidence of retinopathy and posterior vitreous detachment.Additionally,symptoms of ocular axis elongation,lens nucleus hardening,and vitreous liquefaction have become more prevalent.While conventional extracapsular cataract extraction is commonly employed,it often yields suboptimal visual outcomes.Subsequent advancements in cataract phacoemulsification and lens implantation surgeries have gained widespread acceptance for their ability to improve refraction and significantly improve uncorrected visual acuity.AIM To investigate the effect of capsular treatment after phacoemulsification lens implantation in myopic patients with cataract.METHODS We selected 110 patients(with 134 eyes)with myopia and cataracts treated.These patients were categorized into two groups:an observation group(57 patients with 70 eyes)and a control group(53 patients with 64 eyes).The control group underwent cataract phacoemulsification and lens implantation,while the observation group received a refined capsular treatment based on the control group’s procedure.We assessed the differences in visual acuity and quality between the two groups before and after surgery.RESULTS At six months post-operation,the observation group exhibited significantly improved far vision,intermediate vision,near vision,lower objective scattering index,higher Modulation transfer function cut-off frequency,and overall vision metrics at different contrast levels(100%,20%and 9%)compared to the control group(P<0.05).The total score of the National Eye Institute Visual Function Questionnaire in the observation group at 6 months after operation was significantly higher than that in the control group(P<0.05).No significant difference in the incidence of adverse reactions was observed between the observation group and control group(P>0.05).CONCLUSION Capsular treatment demonstrates efficacy in improving visual acuity and quality after phacoemulsification lens implantation in myopic patients with cataracts,warranting its clinical application. 展开更多
关键词 Capsular treatment MYOPIA CATARACT Phacoemulsification and lens implantation Visual acuity Visual quality Uncorrected visual acuity
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Correlation between cerebral neurotransmitters levels by proton magnetic resonance spectroscopy and HbA1c in patients with type 2 diabetes
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作者 Xiang-Yu Gao Chen-Xia Zhou +5 位作者 Hong-Mei Li Min Cheng Da Chen Zi-Yi Li bo feng Jun Song 《World Journal of Diabetes》 SCIE 2024年第6期1263-1271,共9页
BACKGROUND Cognitive dysfunction is the main manifestation of central neuropathy.Although cognitive impairments tend to be overlooked in patients with diabetes mellitus(DM),there is a growing body of evidence linking ... BACKGROUND Cognitive dysfunction is the main manifestation of central neuropathy.Although cognitive impairments tend to be overlooked in patients with diabetes mellitus(DM),there is a growing body of evidence linking DM to cognitive dysfunction.Hyperglycemia is closely related to neurological abnormalities,while often disregarded in clinical practice.Changes in cerebral neurotransmitter levels are associated with a variety of neurological abnormalities and may be closely related to blood glucose control in patients with type 2 DM(T2DM).AIM To evaluate the concentrations of cerebral neurotransmitters in T2DM patients exhibiting different hemoglobin A1c(HbA1c)levels.METHODS A total of 130 T2DM patients were enrolled at the Department of Endocrinology of Shanghai East Hospital.The participants were divided into four groups according to their HbA1c levels using the interquartile method,namely Q1(<7.875%),Q2(7.875%-9.050%),Q3(9.050%-11.200%)and Q4(≥11.200%).Clinical data were collected and measured,including age,height,weight,neck/waist/hip circumferences,blood pressure,comorbidities,duration of DM,and biochemical indicators.Meanwhile,neurotransmitters in the left hippocampus and left brainstem area were detected by proton magnetic resonance spectroscopy.RESULTS The HbA1c level was significantly associated with urinary microalbumin(mALB),triglyceride,low-density lipoprotein cholesterol(LDL-C),homeostasis model assessment of insulin resistance(HOMA-IR),and beta cell function(HOMA-β),N-acetylaspartate/creatine(NAA/Cr),and NAA/choline(NAA/Cho).Spearman correlation analysis showed that mALB,LDL-C,HOMA-IR and NAA/Cr in the left brainstem area were positively correlated with the level of HbA1c(P<0.05),whereas HOMA-βwas negatively correlated with the HbA1c level(P<0.05).Ordered multiple logistic regression analysis showed that NAA/Cho[Odds ratio(OR):1.608,95%confidence interval(95%CI):1.004-2.578,P<0.05],LDL-C(OR:1.627,95%CI:1.119-2.370,P<0.05),and HOMA-IR(OR:1.107,95%CI:1.031-1.188,P<0.01)were independent predictors of poor glycemic control.CONCLUSION The cerebral neurotransmitter concentrations in the left brainstem area in patients with T2DM are closely related to glycemic control,which may be the basis for the changes in cognitive function in diabetic patients. 展开更多
关键词 Type 2 diabetes mellitus Hemoglobin A1c Proton magnetic resonance spectroscopy NEUROTRANSMITTERS Central neuropathy
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On the rule of mixtures for bimetal composites without bonding 被引量:1
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作者 bo feng Xiaowei feng +4 位作者 Changjian Yan Yunchang Xin Haiyan Wang Juan Wang Kaihong Zheng 《Journal of Magnesium and Alloys》 SCIE EI CAS 2020年第4期1253-1261,共9页
In the present study,three types of bimetal composites,Al 6082 sleeve/Al 6082 core,Mg AZ31 sleeve/Mg AZ31 core and Al 6082 sleeve/Mg AZ31 core,were fabricated by drilling and assembling.The rule of mixtures(ROM)for th... In the present study,three types of bimetal composites,Al 6082 sleeve/Al 6082 core,Mg AZ31 sleeve/Mg AZ31 core and Al 6082 sleeve/Mg AZ31 core,were fabricated by drilling and assembling.The rule of mixtures(ROM)for the flow curves and yield strengths during compressive test were addressed.Our results show that the ROM can predict well the experimental flow curves and yield strengths of bimetal composites without bonding,irrespectively of the different strain hardening behavior between the two components. 展开更多
关键词 Magnesium alloys Aluminum alloys COMPOSITES Mechanical behavior
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Experimental study on advanced bone regeneration by BMP-7 derived-peptide chitosan nanometer hydroxyapatite collagen biomimetic composite
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作者 bo feng Dongxu Hu Yangde Zhang 《Discussion of Clinical Cases》 2016年第2期16-21,共6页
Objective:To investigate the effect of BMP-7 derived-peptide chitosan nanometer hydroxyapatite biomimetic collagen composite on repairing rat critical-sized cranial defects.Methods:The chitosan nanometer hydroxyapatit... Objective:To investigate the effect of BMP-7 derived-peptide chitosan nanometer hydroxyapatite biomimetic collagen composite on repairing rat critical-sized cranial defects.Methods:The chitosan nanometer hydroxyapatite collagen composite was prepared and the microcosmic appearance of the composite was observed by scanning electron microscope.The BMP-7 derived-peptide was introduced into the composite by vacuum adsorption.The released peptide content from the scaffold was detected using high performance liquid chromatography at different set times.Critical-sized cranial defects were created on both sides of the parietal bone in 24 adult Sprague-Dawley rats.The BMP-7 derived-peptide chitosan nanometer hydroxyapatite biomimetic collagen composites were implanted on the right side as experimental group and the left side was implanted with chitosan nanometer hydroxyapatite biomimetic collagen composites alone as control group.The rats of both groups were killed in batch respectively after 6 and 12 weeks.Macroscopic observation,three-dimensional reconstruction of computed tomography(CT)and histological observation were performed on these samples.Results:The results of scanning electron microscope showed that the surface of the scaffold was porous.The releasing character of BMP-7 derived-peptide belonged to slow release.The result of animal experiment showed that the BMP-7 derived-peptide chitosan nanometer hydroxyapatite biomimetic collagen composite could more effectively promote the repair of cranial bone defects comparing with the chitosan nanometer hydroxyapatite biomimetic collagen composite alone.The difference was statistically significant(p<.05).Conclusions:The BMP-7 derived-peptide chitosan nanometer hydroxyapatite collagen biomimetic composite can effectively promote bone regeneration of bone defects.The composite is a kind of ideal scaffold material for bone tissue engineering. 展开更多
关键词 BMP-7 derived-peptide Scaffold material Cranial defects Bone tissue engineering
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Identification and validation of major QTL for grain size and weight in bread wheat(Triticum aestivum L.) 被引量:2
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作者 Guangsi Ji Zhibin Xu +7 位作者 Xiaoli Fan Qiang Zhou Liangen Chen Qin Yu Simin Liao Cheng Jiang bo feng Tao Wang 《The Crop Journal》 SCIE CSCD 2023年第2期564-572,共9页
Grain size and weight are key components of wheat yield.Exploitation of major underlying quantitative trait loci(QTL)can improve yield potential in wheat breeding.A recombinant inbred line(RIL)population was construct... Grain size and weight are key components of wheat yield.Exploitation of major underlying quantitative trait loci(QTL)can improve yield potential in wheat breeding.A recombinant inbred line(RIL)population was constructed to detect QTL for thousand-grain weight(TGW),grain length(GL)and grain width(GW)across eight environments.Genomic regions associated with grain size and grain weight were identified on chromosomes 4A and 6A using bulked segregant exome sequencing(BSE-Seq)analysis.After constructing genetic maps,six major QTL detected in at least four individual environments and in best linear unbiased estimator(BLUE)datasets,explained 7.50%-23.45%of the phenotypic variation.Except for QGl.cib-4A,the other five QTL were co-located in two regions,namely QTgw/Gw.cib-4A and QTgw/Gw/Gl.cib-6A.Interactions of these QTL were analyzed.Unlike QTgw/Gw/Gl.cib-6A,QTgw/Gw.cib-4A and QGl.cib-4A had no effect on grain number per spike(GNS).The QTL were validated in a second cross using Kompetitive Allele Specific PCR(KASP)markers.Since QTgw/Gw.cib-4A was probably a novel locus,it and the KASP markers reported here can be used in wheat breeding.TraesCS4A03G0191200 was predicted to be potential candidate gene for QTgw/Gw.cib-4A based on the sequence differences,spatiotemporal expression patterns,gene annotation and haplotype analysis.Our findings will be useful for fine mapping and for marker-assisted selection in wheat grain yield improvement. 展开更多
关键词 BSE-Seq Thousand-grain weight Grain length Grain width QTL mapping
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Flotation separation depressants for scheelite and calcium-bearing minerals: A review 被引量:2
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作者 Ziming Wang bo feng Yuangan Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第9期1621-1632,共12页
Owing to the depletion of wolframite, the focus of tungsten extraction has gradually shifted to scheelite. However, separating the associated minerals(e.g., apatite, fluorite, and calcite) and scheelite is challenging... Owing to the depletion of wolframite, the focus of tungsten extraction has gradually shifted to scheelite. However, separating the associated minerals(e.g., apatite, fluorite, and calcite) and scheelite is challenging because their surface physicochemical properties are similar to those of scheelite. Fortunately, researchers have made substantial progress in separating the minerals of scheelite by using depressants. This study reviews the application and inhibition mechanism of inorganic depressants in obtaining tungsten from its calcium-bearing minerals. The application of new organic depressants in obtaining tungsten from its calcium-bearing minerals and the associated mechanisms are also summarized. After an objective assessment of inorganic and organic depressants’ advantages and disadvantages, possible future research directions for inorganic and organic depressants are proposed. Herein, we provide a theoretical basis for developing scheelite flotation depressants. 展开更多
关键词 SCHEELITE calcium-bearing minerals FLOTATION depressant
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Direct field-to-pattern monolithic design of holographic metasurface via residual encoderdecoder convolutional neural network 被引量:1
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作者 Ruichao Zhu Jiafu Wang +7 位作者 Tianshuo Qiu Dingkang Yang bo feng Zuntian Chu Tonghao Liu Yajuan Han Hongya Chen Shaobo Qu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第8期29-38,共10页
Complex-amplitude holographic metasurfaces(CAHMs)with the flexibility in modulating phase and amplitude profiles have been used to manipulate the propagation of wavefront with an unprecedented level,leading to higher ... Complex-amplitude holographic metasurfaces(CAHMs)with the flexibility in modulating phase and amplitude profiles have been used to manipulate the propagation of wavefront with an unprecedented level,leading to higher image-reconstruction quality compared with their natural counterparts.However,prevailing design methods of CAHMs are based on Huygens-Fresnel theory,meta-atom optimization,numerical simulation and experimental verification,which results in a consumption of computing resources.Here,we applied residual encoder-decoder convolutional neural network to directly map the electric field distributions and input images for monolithic metasurface design.A pretrained network is firstly trained by the electric field distributions calculated by diffraction theory,which is subsequently migrated as transfer learning framework to map the simulated electric field distributions and input images.The training results show that the normalized mean pixel error is about 3%on dataset.As verification,the metasurface prototypes are fabricated,simulated and measured.The reconstructed electric field of reverse-engineered metasurface exhibits high similarity to the target electric field,which demonstrates the effectiveness of our design.Encouragingly,this work provides a monolithic field-to-pattern design method for CAHMs,which paves a new route for the direct reconstruction of metasurfaces. 展开更多
关键词 metasurface HOLOGRAPHY complex amplitude deep learning monolithic design
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A 3D analysis of the occurrence of fractures in hot dry rock reservoirs based on the spatial distribution of natural fractures 被引量:1
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作者 Siqing He bo feng +4 位作者 Jinshou Zhu Xiyao Liu Shuantong ShangGuan Xiaofei Qi Jiulong Liu 《Energy Geoscience》 2023年第4期95-107,共13页
Hot dry rock(HDR)geothermal energy is a kind of widely distributed clean energy with huge reserves.However,its commercial development has been constrained by reservoir stimulation.In the early stage of HDR geothermal ... Hot dry rock(HDR)geothermal energy is a kind of widely distributed clean energy with huge reserves.However,its commercial development has been constrained by reservoir stimulation.In the early stage of HDR geothermal energy development,properly determining spatial distribution patterns of natural fractures in HDR reservoirs can effectively guide reservoir stimulation.This study analyzes the spatial distribution of natural fractures by using FracMan software based on the actual geological data and log data of well M-2 in the Matouying Uplift area,Hebei Province.The fracture parameters are counted and Monte Carlo simulation technique is introduced to optimize the parameters,which makes the natural fracture model more accurate and reliable.Furthermore,this study simulates hydraulic fracturing using the model combined with the actual in-situ stress parameters and the construction scheme.As verified by fitting the changes in simulated wellhead pressure during hydraulic fracturing with the actual wellhead pressure data detected during construction,the methods for natural fracture modeling used in this study are scientific and reasonable.The preliminary prediction results show that the displacement design scheme with a pump displacement of 2.0-3.0 m^(3)/min,4.0-5.5 m^(3)/min and 6-7 m^(3)/min in the early,middle and late stages,respectively,has good fracturing effect.The results of this study can be utilized as a reference for preparing development schemes for HDR reservoirs. 展开更多
关键词 Natural fracture Hot dry rock Reservoir modeling
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基于机器学习和第一性原理计算构建双电子转移通道加速CO_(2)光还原
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作者 王立晶 杨天一 +5 位作者 冯博 许祥雨 申玉莹 李孜涵 Arramel 江吉周 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第11期265-277,共13页
光催化还原CO_(2)技术可以将CO_(2)转化为高附加值化学品,在解决日益严重的环境污染和能源危机方面具有巨大潜力.然而,CO_(2)分子较高的C=O键键能(750 kJ mol^(-1))为其活化和还原带来了挑战.因此,构建具有新型电子转移路径的光催化剂... 光催化还原CO_(2)技术可以将CO_(2)转化为高附加值化学品,在解决日益严重的环境污染和能源危机方面具有巨大潜力.然而,CO_(2)分子较高的C=O键键能(750 kJ mol^(-1))为其活化和还原带来了挑战.因此,构建具有新型电子转移路径的光催化剂具有重要意义.与传统的单电子传输通道相比,层状材料的多电子传输通道在改善载流子传输能力方面具有明显的优势.然而,设计具有合适参数的多电子通道光催化剂模型仍是重要挑战.本文首先采用理论计算预测了具有双电子转移通道、参数匹配的三元异质结BiOBr-Bi-g-C_(3)N_(4);然后,通过机器学习探讨了各种实验参数对双电子传输通道的光催化活性影响的线性规律,优化了实验参数,制备了光催化活性较高的BiOBr-Bi-g-C_(3)N_(4)催化剂;最后,结合第一性原理计算和实验表征结果揭示了其光催化机理.理论计算结果表明,BiOBr-Bi-g-C_(3)N_(4)异质结具有最佳的吉布斯自由能(|ΔG|),有利于光催化H_(2)O解离和CO_(2)还原.实验发现,在300 W Xe灯照射下,CO_(2)还原光催化活性高达43μmol g^(-1)h^(-1).与Bi-BiOBr和Bi-g-C_(3)N_(4)相比,BiOBr-Bi-g-C_(3)N_(4)催化CO_(2)还原:的速率分别提高了约4.7倍和3.1倍.分析新型结构催化剂之所以具有良好的活性,主要有以下三个原因:(1)三者之间匹配的功函数使得BiOBr和g-C_(3)N_(4)纳米片可以与Bi形成肖特基异质结,在光照下,电子从BiOBr和g-C_(3)N_(4)向Bi转移;此外,g-C_(3)N_(4)纳米片与BiOBr具有相似的层间结构和匹配的能级结构,有利于形成Bi-BiOBr和Bi-g-C_(3)N_(4)双电子传输通道,从而实现载流子的有效分离和转移.(2)丰富的Bi活性位点可以抑制光生载流子的随机分布,使其限域在BiOBr与g-C_(3)N_(4)层间;这些载流子在特定的时间尺度上产生了独特的叠加态,优化了CO_(2)还原的多电子反应动力学路径.(3)g-C_(3)N_(4)的引入提高了Bi-BiOBr的太阳光利用率和比表面积.综上所述,本文成功地预测、设计和制备了一种具有双电子传输通道的新型三元异质结BiOBr-Bi-g-C_(3)N_(4)光催化剂,其表现出较高的光催化CO_(2)还原性能.理论计算和实验结果表明,BiOBr和g-C_(3)N_(4)相似的层间结构和匹配的能级结构使得具有不同弛豫时间的电子能够形成相干态;而Bi作为CO_(2)还原的良好活性位点,能够同时提高BiOBr和g-C_(3)N_(4)的载流子转移性能.因此,具有不同寿命的电子可以参与到CO_(2)还原的过程中去.本文可为高性能CO_(2)还原光催化剂的精准预测和合理设计提供实验和理论参考. 展开更多
关键词 双电子转移通道 光催化还原CO_(2) 机器学习 第一性原理计算
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Design and analysis of longitudinal–flexural hybrid transducer for ultrasonic peen forming
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作者 Wuqin Li Yongyong Zhu +4 位作者 Xiaolong Lu Huafeng Li Ying Wei Pengwei Shang bo feng 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第4期30-39,共10页
Ultrasonic peen forming(UPF)is an emerging technology that exhibits great superiority in both its flexible operating modes and the deep residual stress that it produces compared with conventional plastic forming metho... Ultrasonic peen forming(UPF)is an emerging technology that exhibits great superiority in both its flexible operating modes and the deep residual stress that it produces compared with conventional plastic forming methods.Although ultrasonic transducers with longitudinal vibration have been widely studied,they have seldom been incorporated into UPF devices for machining in confined spaces.To meet the requirements of this type of machining,a sandwich-type piezoelectric transducer with coupled longitudinal-flexural vibrational modes is proposed.The basic structure of the transducer is designed to obtain large vibrational amplitudes in both modes.Experimental results obtained with a prototype device demonstrate the feasibility of the proposed transducer.The measured vibrational amplitude for the working face in the longitudinal vibrational mode is 1.0μm,and electrical matching increases this amplitude by 40%.The flexural vibration characteristics of the same prototype transducer are also tested and are found to be slightly smaller than those of longitudinal mode.The resultant working strokes of the UPF impact pins reach 1.7 mm and 1.2 mm in the longitudinal and flexural modes,respectively.The forming capability of the prototype has been evaluated via 15-min machining on standard 2024-T351 aluminum plates.After UPF,an improved surface morphology with lower surface roughness is obtained.The aluminum plate test piece has an apparent upper deformation with an arc height of 0.64 mm.The measured peak value of the compressive residual stress is around 250 MPa,appearing at a depth of 100μm.The proposed longitudinal-flexural hybrid transducer thus provides a high-performance tool for plate peen forming in confined spaces. 展开更多
关键词 Ultrasonic peen forming Piezoelectric transducer Longitudinal-flexural vibrational mode Modal analysis
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Lower alanine aminotransferase levels are associated with increased all-cause and cardiovascular mortality in nonalcoholic fatty liver patients
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作者 Jia-Rui Zheng Zi-Long Wang +2 位作者 Su-Zhen Jiang Hong-Song Chen bo feng 《World Journal of Hepatology》 2023年第6期813-825,共13页
BACKGROUND Serum alanine aminotransferase(ALT) levels are often considered a marker to evaluate liver disease and its severity.AIM To investigate the association between ALT levels and all-cause and cause-specific mor... BACKGROUND Serum alanine aminotransferase(ALT) levels are often considered a marker to evaluate liver disease and its severity.AIM To investigate the association between ALT levels and all-cause and cause-specific mortality in patients with nonalcoholic fatty liver disease(NAFLD).METHODS The Third National Health and Nutrition Examination Survey(NHANES-Ⅲ) from 1988 to 1994 and NHANES-Ⅲ-related mortality data from 2019 onward were used to obtain the necessary data for the study. NAFLD was defined as hepatic steatosis, as diagnosed by ultrasound, with no other liver diseases. ALT levels were categorized into four groups according to the different recommended upper limits of normal(ULN) in men and women: < 0.5 ULN, 0.5-1 ULN, 1-2 ULN, and ≥ 2 ULN. The hazard ratios for all-cause mortality and cause-specific mortality were analyzed using the Cox proportional hazard model.RESULTS Multivariate logistic regression analysis demonstrated that the odds ratio of NAFLD correlated positively with increased serum ALT levels. In patients with NAFLD, all-cause mortality and cardiovascular mortality were the highest when ALT was < 0.5 ULN, yet cancer-related mortality was the highest when ALT was ≥ 2 ULN. The same results could be found in both men and women. Univariate analysis showed that severe NAFLD with normal ALT levels had the highest allcause and cause-specific mortality, but the difference was not statistically significant after adjustment for age and multivariate factors.CONCLUSION The risk of NAFLD was positively correlated with ALT level, but all-cause and cardiovascular mortality were the highest when ALT was < 0.5 ULN. Regardless of the severity of NAFLD, normal or lower ALT levels were associated with higher mortality than elevated ALT levels. Clinicians should be aware that high ALT levels indicate liver injury, but low ALT levels are associated with a higher risk of death. 展开更多
关键词 Non-alcoholic fatty liver disease Alanine aminotransferase MORTALITY NHANES-Ⅲ
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Paths for Integrating Local Red Culture into Ideological and Political Courses of Agronomy Majors
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作者 Wenzhao LI Xiong YAN +3 位作者 Feifei HUO bo feng Yunchao WANG Zhan YU 《Asian Agricultural Research》 2023年第3期55-58,共4页
Local red culture is an important educational resource.Integrating it into the course of agronomy majors is an important part of cultivating applied talents who grasp and love agriculture in the new era.This paper ana... Local red culture is an important educational resource.Integrating it into the course of agronomy majors is an important part of cultivating applied talents who grasp and love agriculture in the new era.This paper analyzes the necessity of integrating local red culture into courses of agronomy majors,discusses the current challenges,and puts forward specific recommendations. 展开更多
关键词 Local red culture Agronomy majors Ideological and political courses
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Recovery of cyanophycin granule polypeptide from activated sludge: carbon source dependence and aggregation-induced luminescence characteristics
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作者 Kui Zou Hongyuan Liu +2 位作者 bo feng Taiping Qing Peng Zhang 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2024年第2期25-34,共10页
In the sewage treatment process,facilitating the conversion of pollutants into value-added resources holds great potential for reducing the amount of greenhouse gas emissions and promoting economic circulation.Cyanoph... In the sewage treatment process,facilitating the conversion of pollutants into value-added resources holds great potential for reducing the amount of greenhouse gas emissions and promoting economic circulation.Cyanophycin granule polypeptide(CGP),a recently discovered high value-added biopolymer present in activated sludge,has provided new avenues for the recovery of resources.However,the mechanisms that regulate CGP synthesis and the characteristics of this biopolymer in activated sludge remain unclear thus far.This study investigated the synthesis of CGP,polyhydroxyalkanoates(PHA),and alginate-like exopolysaccharides(ALE)in various microbial aggregates under different carbon sources feeding conditions.Our results showed that the CGP yields was superior that of PHA and ALE when subjected to identical carbon source feeding conditions.Furthermore,biofilm was more conducive to CGP accumulation than floc sludge.Compared with glucose and methanol,sodium acetate significantly enriched the CGP synthetase-encoding gene(cphAabundance=~17419),resulting in the highest CGP yield(average 107.1 mg/g MLSS)in both biofilm and floc sludge.This study is the first to reported the characteristic fluorescence of CGP(Ex/Em=~360/450 nm)caused by the aggregated luminescence of arginine on the side chains.Overall,this study highlights the potential application of CGP as a fluorescent material and offers insights into CGP recovery from activated sludge in wastewater treatment plants. 展开更多
关键词 Cyanophycin POLYHYDROXYALKANOATE Alginate-like exopolysaccharides Bioresource recovery Aggregation-induced luminescence
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Advances in geothermal exploration and production:Introduction
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作者 Zhiliang He Shu Jiang +1 位作者 Haibing Shao bo feng 《Energy Geoscience》 2023年第4期9-10,共2页
Geothermal resources are a renewable and clean energy source that is not affected by weather,day and night,or seasonal changes.If large-scale development and utilization can be achieved(Gerald,2021),it will have impor... Geothermal resources are a renewable and clean energy source that is not affected by weather,day and night,or seasonal changes.If large-scale development and utilization can be achieved(Gerald,2021),it will have important strategic and practical significance for ensuring energy supply in human society and achieving the“dual carbon goals”(Ma,2023). 展开更多
关键词 WEATHER goals STRATEGIC
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Intersection theory rules symbology
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作者 Jiaqi Chen bo feng Lilin Yang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2024年第2期93-104,共12页
We propose a novel method to determine the structure of symbols for any family of polylogarithmic Feynman integrals.Using the d log-bases and simple formulas for the leading order and next-to-leading contributions to ... We propose a novel method to determine the structure of symbols for any family of polylogarithmic Feynman integrals.Using the d log-bases and simple formulas for the leading order and next-to-leading contributions to the intersection numbers,we give a streamlined procedure to compute the entries in the coefficient matrices of canonical differential equations,including the symbol letters and the rational coefficients.We also provide a selection rule to decide whether a given matrix element must be zero.The symbol letters are deeply related to the poles of the integrands and also have interesting connections to the geometry of Newton polytopes.Our method can be applied to many cutting-edge multi-loop calculations.The simplicity of our results also hints at the possible underlying structure in perturbative quantum field theories. 展开更多
关键词 scattering amplitude Feynman integral symbology
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