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基于多性状模型内蒙古绒山羊早期生长性状基因组预测准确性研究
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作者 高林豫 许琦 +10 位作者 何钰霄 习海娇 刘一帆 张涛 李金泉 张燕军 王瑞军 吕琦 梅步俊 苏蕊 王志英 《遗传》 CAS CSCD 北大核心 2024年第5期421-430,共10页
内蒙古绒山羊是经过长期自然选择和人工选育后形成的优良家畜品种,是目前世界一流的绒肉兼用山羊。多性状动物模型被认为可以显著提高畜禽遗传评估的准确性,实现性状间的间接选择。本文基于内蒙古绒山羊个体的系谱、基因型、环境以及早... 内蒙古绒山羊是经过长期自然选择和人工选育后形成的优良家畜品种,是目前世界一流的绒肉兼用山羊。多性状动物模型被认为可以显著提高畜禽遗传评估的准确性,实现性状间的间接选择。本文基于内蒙古绒山羊个体的系谱、基因型、环境以及早期生长性状的表型记录,建立多性状动物模型,利用ABLUP、GBLUP、ssGBLUP三种方法进行早期生长性状(初生重、断乳重、断乳前平均日增重、周岁重)遗传参数及基因组育种值的估计,进一步利用五倍交叉验证方法评价基因组育种值估计准确性和可靠性。结果显示,3种方法估计的初生重遗传力为0.13~0.15,断乳重遗传力为0.13~0.20,日增重遗传力为0.11~0.14,周岁重遗传力为0.09~0.14,均属于中等偏低遗传力;断乳重和日增重、日增重和周岁重之间存在强的正遗传相关,相关系数分别为0.77~0.79和0.56~0.67,表型相关发现同样的规律;ABLUP、GBLUP和ssGBLUP法估计的初生重育种值准确性分别为0.5047、0.6694、0.7156,断乳重分别为0.6207、0.6456、0.7254;日增重分别为0.6110、0.6855、0.7357,周岁重分别为0.6209、0.7155、0.7756。综上所述,内蒙古绒山羊早期生长性状属于中等偏低遗传力,对其进行遗传选育改良速度相对较慢;通过对断乳重的选择可以实现其他生长性状的遗传改良;ssGBLUP方法估计内蒙古绒山羊早期生长性状基因组育种值的准确性和可靠性均最高,且显著高于ABLUP法,说明该方法是内蒙古绒山羊早期性状基因组选育的最佳方法。 展开更多
关键词 内蒙古绒山羊 早期生长性状 多性状动物模型 基因组育种值估计准确性
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Engineering of geometrical configurations in dual-atom catalysts for electrocatalytic applications
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作者 Tao Zhang yifan liu +3 位作者 Liang Xue Jingwen Sun Pan Xiong Junwu Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期273-287,共15页
Geometrical configurations play a crucial role in dual-atom catalysts(DACs)for electrocatalytic applications.Significant progress has been made to design DACs electrocatalysts with various geometri-cal configurations,... Geometrical configurations play a crucial role in dual-atom catalysts(DACs)for electrocatalytic applications.Significant progress has been made to design DACs electrocatalysts with various geometri-cal configurations,but in-depth understanding the relationship between geometrical configurations and metal-metal interaction mechanisms for designing targeted DACs is still required.In this review,the recent progress in engineering of geometrical configurations of DACs is systematically summarized.Based on the polarity of geometrical configuration,DACs can be classified into two different types that are homonuclear and heteronuclear DACs.Furthermore,with regard to the geometrical configurations of the active sites,homonuclear DACs are identified into adjacent and bridged configurations,and heteronuclear DACs can be classified into adjacent,bridged,and separated configurations.Subsequently,metal-metal interactions in DACs with different geometrical configurations are introduced.Additionally,the applications of DACs in different electrocatalytic reactions are discussed,including the oxygen reduction reaction(ORR),oxygen evolution reaction(OER),hydrogen evolution reaction(HER),and other catalysis.Finally,the future challenges and perspectives for advancements in DACs are high-lighted.This review aims to provide inspiration for the design of highly effcient DACs towards energy relatedapplications. 展开更多
关键词 Dual-atom catalysts Geometrical configurations HOMONUCLEAR HETERONUCLEAR ELECTROCATALYSIS
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A Review of Hybrid Cyber Threats Modelling and Detection Using Artificial Intelligence in IIoT
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作者 yifan liu Shancang Li +1 位作者 Xinheng Wang Li Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1233-1261,共29页
The Industrial Internet of Things(IIoT)has brought numerous benefits,such as improved efficiency,smart analytics,and increased automation.However,it also exposes connected devices,users,applications,and data generated... The Industrial Internet of Things(IIoT)has brought numerous benefits,such as improved efficiency,smart analytics,and increased automation.However,it also exposes connected devices,users,applications,and data generated to cyber security threats that need to be addressed.This work investigates hybrid cyber threats(HCTs),which are now working on an entirely new level with the increasingly adopted IIoT.This work focuses on emerging methods to model,detect,and defend against hybrid cyber attacks using machine learning(ML)techniques.Specifically,a novel ML-based HCT modelling and analysis framework was proposed,in which L1 regularisation and Random Forest were used to cluster features and analyse the importance and impact of each feature in both individual threats and HCTs.A grey relation analysis-based model was employed to construct the correlation between IIoT components and different threats. 展开更多
关键词 Cyber security Industrial Internet of Things artificial intelligence machine learning algorithms hybrid cyber threats
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Anti-Jamming Null Space Projection Beamforming Based on Symbiotic Radio
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作者 Baofeng Ji yifan liu +6 位作者 Tingpeng Li Ling Xing Weixing Wang Shahid Mumtaz Xiaolong Shang Wanying liu Congzheng Han 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期679-689,共11页
With the development of information technology,more and more devices are connected to the Internet through wireless communication to complete data interconnection.Due to the broadcast characteristics ofwireless channe... With the development of information technology,more and more devices are connected to the Internet through wireless communication to complete data interconnection.Due to the broadcast characteristics ofwireless channels,wireless networks have suffered more and more malicious attacks.Physical layer security has received extensive attention from industry and academia.MIMO is considered to be one of the most important technologies related to physical layer security.Through beamforming technology,messages can be transmitted to legitimate users in an offset direction that is as orthogonal as possible to the interference channel to ensure the reception SINR by legitimate users.Combining the symbiotic radio(SR)technology,this paper considers a symbiotic radio antijamming MIMO system equipped with a multi-antenna system at the main base station.In order to avoid the interference signal and improve the SINR of the signal received by the user.The base station is equipped with a uniform rectangular antenna array,and using Null Space Projection(NSP)Beamforming,Intelligent Reflecting Surface(IRS)can assist in changing the beam’s angle.The simulation results show that NSP Beamforming could make a better use of the null space of interference,which can effectively improve the received SINR of users under directional interference,and improve the utilization efficiency of signal energy. 展开更多
关键词 Symbiotic radio ANTI-JAMMING MIMO NSP Beamforming physical layer security
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Distal margin distance in radical resection of locally advanced rectal cancer after neoadjuvant therapy
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作者 Jun Luo Mingxuan Zhu +6 位作者 Long Zhao Meiwen He Bei Li yifan liu Yuhan Sun Guoqing Lyu Zhanlong Shen 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第2期226-232,共7页
Colorectal cancer has a high incidence and mortality rate in China, with the majority of cases being middle and low rectal cancer. Surgical intervention is currently the main treatment modality for locally advanced re... Colorectal cancer has a high incidence and mortality rate in China, with the majority of cases being middle and low rectal cancer. Surgical intervention is currently the main treatment modality for locally advanced rectal cancer, with the common goal of improving oncological outcomes while preserving function. The controversy regarding the circumferential resection margin distance in rectal cancer surgery has been resolved. With the promotion of neoadjuvant therapy concepts and advancements in technology, treatment strategies have become more diverse.Following tumor downstaging, there is an increasing trend towards extending the safe distance of distal rectal margin. This provides more opportunities for patients with low rectal cancer to preserve their anal function.However, there is currently no consensus on the specific distance of distal resection margin. 展开更多
关键词 Colorectal cancer distal resection margin neoadjuvant therapy
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Response Surface Methodology-Based SERS for Determination of Gymnodimine
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作者 Siyang Chan Yaoyi Wu +2 位作者 yifan liu Donghang Yin Fei Wang 《American Journal of Analytical Chemistry》 2023年第8期305-325,共21页
Gymnodimine (GYM), a fast-acting marine toxin, is destructive to aquaculture and human health through contaminated shellfish. The current detection methods in GYM have definite drawbacks in operation, such as the dema... Gymnodimine (GYM), a fast-acting marine toxin, is destructive to aquaculture and human health through contaminated shellfish. The current detection methods in GYM have definite drawbacks in operation, such as the demand for delicate instruments and the consumption of time. Therefore, silver colloid was utilized as a surface-enhanced Raman scattering (SERS) desirable substrate for sensitive and rapid detection of GYM in lake and shellfish samples. The theoretical spectrum of GYM is calculated by density functional theory (DFT), and the substrate performance is evaluated by a rhodamine 6 G probe. Under the optimal SERS experimental condition calculated by the response surface methodology, the low limit of detection of 0.105 μM with R<sup>2</sup> of 0.9873 and a broad linearity range of 0.1 - 10 μM was achieved for GYM detection. In addition, the substrate was satisfyingly applied to detect gymnodimine in the lake and shellfish matrix samples with LOD as low as 0.148 μM and 0.170 μM, respectively. These results demonstrated a promising SERS platform for detecting marine toxins in seafood for food safety and pharmaceutical research. 展开更多
关键词 Surface-Enhanced Raman Scattering Gymnodimine Ag Colloid Box-Behnken Design Response Surface Methodology
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巯基纤维素吸附剂去除染料-Cr(Ⅵ)复合污染的作用机制
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作者 刘燕铃 刘以凡 +3 位作者 吕源财 叶晓霞 林春香 刘明华 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第10期9-19,共11页
以α-纤维素为原料,采用高碘酸钠氧化法对纤维素进行改性制备了巯基纤维素吸附剂(Cell-SH),采用扫描电镜、傅里叶变换红外光谱及X射线光电子能谱对Cell-SH的形貌和结构进行表征,系统考察了Cell-SH对水溶液中孔雀石绿(MG)和六价铬(Cr(Ⅵ)... 以α-纤维素为原料,采用高碘酸钠氧化法对纤维素进行改性制备了巯基纤维素吸附剂(Cell-SH),采用扫描电镜、傅里叶变换红外光谱及X射线光电子能谱对Cell-SH的形貌和结构进行表征,系统考察了Cell-SH对水溶液中孔雀石绿(MG)和六价铬(Cr(Ⅵ))复合污染的去除效果、影响因素及机理。结果表明,氧化改性后,Cell-SH表面含有—SH官能团,对MG-Cr(Ⅵ)复合污染具有良好的去除性能,其对二者的吸附量分别为58.9 mg/g和28.7 mg/g;吸附剂表面还同时存在MG与Cr(Ⅵ)的络合物,吸附过程涉及氢键结合、静电引力、还原作用及螯合作用等作用力。Cell-SH具有去除水溶液中MG和Cr(Ⅵ)复合污染的优异性能,具有较大的应用潜力。 展开更多
关键词 纤维素吸附剂 复合污染 六价铬 孔雀石绿 吸附
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Humanoid Intelligent Display Platform for Audiovisual Interaction and Sound Identification 被引量:2
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作者 Yang Wang Wenli Gao +11 位作者 Shuo Yang Qiaolin Chen Chao Ye Hao Wang Qiang Zhang Jing Ren Zhijun Ning Xin Chen Zhengzhong Shao Jian Li yifan liu Shengjie Ling 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期82-98,共17页
This study proposes a rational strategy for the design,fabrication and system integration of the humanoid intelligent display platform(HIDP)to meet the requirements of highly humanized mechanical properties and intell... This study proposes a rational strategy for the design,fabrication and system integration of the humanoid intelligent display platform(HIDP)to meet the requirements of highly humanized mechanical properties and intelligence for human-machine interfaces.The platform’s sandwich structure comprises a middle lightemitting layer and surface electrodes,which consists of silicon elastomer embedded with phosphor and silk fibroin ionoelastomer,respectively.Both materials are highly stretchable and resilient,endowing the HIDP with skin-like mechanical properties and applicability in various extreme environments and complex mechanical stimulations.Furthermore,by establishing the numerical correlation between the amplitude change of animal sounds and the brightness variation,the HIDP realizes audiovisual interaction and successful identification of animal species with the aid of Internet of Things(IoT)and machine learning techniques.The accuracy of species identification reaches about 100%for 200 rounds of random testing.Additionally,the HIDP can recognize animal species and their corresponding frequencies by analyzing sound characteristics,displaying real-time results with an accuracy of approximately 99%and 93%,respectively.In sum,this study offers a rational route to designing intelligent display devices for audiovisual interaction,which can expedite the application of smart display devices in human-machine interaction,soft robotics,wearable sound-vision system and medical devices for hearing-impaired patients. 展开更多
关键词 Silk fibroin Ionoelastomer Luminescent display Machine learning Audiovisual interaction
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Advances in Research of Molded Pulp for Food Packaging 被引量:1
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作者 yifan liu Shufeng Ma +1 位作者 Feijie Wang Liqiang Wang 《Journal of Renewable Materials》 EI 2023年第11期3831-3846,共16页
The molded pulp,a product of three-dimensional papermaking technology,is environmentally friendly and has a low environmental impact due to its ability to decompose quickly in the natural environment after disposal.Th... The molded pulp,a product of three-dimensional papermaking technology,is environmentally friendly and has a low environmental impact due to its ability to decompose quickly in the natural environment after disposal.The application of molded pulp for food packaging can replace or reduce the use of plastic food packaging.Researchers extract fibers from plants for the production of safe and hygienic molded pulp for food packaging,and they also study and enhance the qualities of molded pulp to broaden its use in the food industry.This paper reviews the sources and varieties of plant fiber used in molded pulp for food packaging,as well as research on the improvement and optimization of the performance of molded pulp products.Additionally,issues with molded pulp’s actual use for food packaging are reviewed,along with the potential for future research.This work can serve as a reference for molded pulp applications and research in the food industry in the future. 展开更多
关键词 Molded pulp food packaging plant fiber PROPERTIES
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The complete mitochondrial genome of Parachiloglanis hodgarti and its phylogenetic position within Sisoridae
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作者 Jiasheng LI Ying PENG +6 位作者 Shufei ZHANG yifan liu Kun ZHANG Jian CHEN Hua ZHANG Chi ZHANG Bingjian liu 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期267-279,共13页
The complete mitogenome of Parachiloglanis hodgarti was sequenced and characterized,which is the first mitogenome of the genus Parachiloglanis within Sisoridae.The mitogenome is 16511-bp long and included 13 protein-c... The complete mitogenome of Parachiloglanis hodgarti was sequenced and characterized,which is the first mitogenome of the genus Parachiloglanis within Sisoridae.The mitogenome is 16511-bp long and included 13 protein-coding genes,22 transfer RNAs,two ribosomal RNAs,and one control region.The genome composition was A+T biased(58.64%)and exhibited a positive AT-skew(0.095)and a negative GC-skew(-0.283).Compared with other Sisoridae fishes,the characteristics of nucleotide skews,codon usage,and amino acid usage of the P.hodgarti mitogenome are more similar to those of non-Glyptosternoid fishes.Furthermore,the phylogenetic trees show that Sisoridae fishes fall into four major clades and P.hodgarti(CladeⅠ)is basal to the Sisoridae family,forming a sister clade to the Glyptosternoids(CladeⅣ).The topological structures constructed in this study raised doubts over the traditional classification system.These results will help better understand the feature s of the P.hodgarti mitogenome and provide a reference for further phylogenetic research on Sisoridae species. 展开更多
关键词 Parachiloglanis hodgarti mitogenomes SISORIDAE glyptosternoids phylogenetic relationship
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Using a New Auxiliary Equation to Construct Abundant Solutions for Nonlinear Evolution Equations 被引量:1
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作者 yifan liu Guojiang Wu 《Journal of Applied Mathematics and Physics》 2021年第12期3155-3164,共10页
In this paper, a new auxiliary equation method is proposed. Combined with the mapping method, abundant periodic wave solutions for generalized Klein-Gordon equation and Benjamin equation are obtained. They are new typ... In this paper, a new auxiliary equation method is proposed. Combined with the mapping method, abundant periodic wave solutions for generalized Klein-Gordon equation and Benjamin equation are obtained. They are new types of periodic wave solutions which are rarely found in previous studies. As <em>m</em> → 0 and <em>m</em> → 1, some new types of trigonometric solutions and solitary solutions are also obtained correspondingly. This method is promising for constructing abundant periodic wave solutions and solitary solutions of nonlinear evolution equations (NLEEs) in mathematical physics. 展开更多
关键词 Auxiliary Equation Method Nonlinear Evolution Equations Periodic Wave Solutions Mapping Method Solitary Wave Solutions
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Research Progress of Perioperative Application of GLP-1 and Its Protective Effects on Organs
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作者 Hong Xi Zhigang Pang +3 位作者 yifan liu Lixiong Xue Jiandong He Wenqu Yang 《Journal of Clinical and Nursing Research》 2023年第4期19-28,共10页
Glucagon-like peptide-1(GLP-1)is a multifunctional hormone with broad pharmacological potential to control inflammation,protect cardiovascular,kidney,and liver functions.Moreover,GLP-1 can also cross the blood-brain b... Glucagon-like peptide-1(GLP-1)is a multifunctional hormone with broad pharmacological potential to control inflammation,protect cardiovascular,kidney,and liver functions.Moreover,GLP-1 can also cross the blood-brain barrier and bind with GLP-1R distributed in various parts of the brain,thereby reducing apoptosis caused by neuroinflammation and oxygen stress,and promoting learning,memory,cognitive function,neuroprotection,and nerve cell remodeling.However,the exact molecular pathway by which GLP-1 receptor agonists(GLP-1RAs)exerts protective effects on many organs is not fully understood,so it is a hot topic of research.In this article,the recent research on the multi-organ protection of GLP-1 is reviewed,with emphasis on the research progress in the field of nervous system and perioperative anesthesia. 展开更多
关键词 Glucagon-like peptide-1 Glucagon-like peptide-1 receptor agonist Protection of organs
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聚乙烯醇接枝聚硅氧烷的制备与性能 被引量:4
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作者 陈娟 张晓梅 +3 位作者 刘一凡 王勃东 姜彦 张洪文 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第8期42-49,共8页
通过阴离子聚合向聚乙烯醇(PVA)中引入聚二甲基硅氧烷,制得以碳为主链、硅氧烷为侧链的亲水性共聚物(PVA-PDMS-OH)。与正硅酸四乙酯进行脱醇硫化制备了耐碱性的交联共聚物,提高了纯PVA-PDMS-OH的耐热和疏水的特性。使用PVA-PDMS-OH的硫... 通过阴离子聚合向聚乙烯醇(PVA)中引入聚二甲基硅氧烷,制得以碳为主链、硅氧烷为侧链的亲水性共聚物(PVA-PDMS-OH)。与正硅酸四乙酯进行脱醇硫化制备了耐碱性的交联共聚物,提高了纯PVA-PDMS-OH的耐热和疏水的特性。使用PVA-PDMS-OH的硫化涂层覆盖改性聚对苯二甲酸乙二醇酯(PET)膜片表面,发现改性PET膜片透光率最高可提升至92.7%。将PVA-PDMS-OH添加到α,ω-二羟基聚二甲基硅氧烷(PDMS-OH)中制得共混硅橡胶。发现在共混硅橡胶中PVA-PDMS-OH的质量分数为10%时,共混硅橡胶的拉伸强度达到0.842 MPa,为纯PDMS-OH硅橡胶的6.7倍;断裂伸长率达到168.2%,为纯PDMS-OH硅橡胶的2.6倍。表明PVA-PDMS-OH可用于提高硅橡胶的拉伸强度和延伸率,改善其韧性,说明它在改进硅橡胶性能方面具有应用前景。 展开更多
关键词 聚乙烯醇 硅氧烷 交联共聚物 硅橡胶 耐碱性
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A Survey: Typical Security Issues of Software-Defined Networking 被引量:12
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作者 yifan liu Bo Zhao +2 位作者 Pengyuan Zhao Peiru Fan Hui liu 《China Communications》 SCIE CSCD 2019年第7期13-31,共19页
Software-Defined Networking (SDN) has been a hot topic for future network development, which implements the different layers of control plane and data plane respectively. Despite providing high openness and programmab... Software-Defined Networking (SDN) has been a hot topic for future network development, which implements the different layers of control plane and data plane respectively. Despite providing high openness and programmability, the “three-layer two-interface” architecture of SDN changes the traditional network and increases the network attack nodes, which results in new security issues. In this paper, we firstly introduced the background, architecture and working process of SDN. Secondly, we summarized and analyzed the typical security issues from north to south: application layer, northbound interface, control layer, southbound interface and data layer. Another contribution is to review and analyze the existing solutions and latest research progress of each layer, mainly including: authorized authentication module, application isolation, DoS/DDoS defense, multi-controller deployment and flow rule consistency detection. Finally, a conclusion about the future works of SDN security and an idealized global security architecture is proposed. 展开更多
关键词 software-defined NETWORKING network SECURITY global SECURITY SECURITY THREAT
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Atomic-Scale Layer-by-Layer Deposition of Fe SiAl@ZnO@Al_(2)O_(3) Hybrid with Threshold Anti-Corrosion and Ultra-High Microwave Absorption Properties in Low-Frequency Bands 被引量:11
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作者 Wei Tian Jinyao Li +5 位作者 yifan liu Rashad Ali Yang Guo Longjiang Deng Nasir Mahmood Xian Jian 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第10期308-321,共14页
Developing highly efficient magnetic microwave absorb-ers(MAs)is crucial,and yet challenging for anti-corrosion properties in extremely humid and salt-induced foggy environments.Herein,a dual-oxide shell of ZnO/Al_(2)... Developing highly efficient magnetic microwave absorb-ers(MAs)is crucial,and yet challenging for anti-corrosion properties in extremely humid and salt-induced foggy environments.Herein,a dual-oxide shell of ZnO/Al_(2)O_(3) as a robust barrier to FeSiAl core is introduced to mitigate corrosion resistance.The FeSiAl@ZnO@Al_(2)O_(3) layer by layer hybrid structure is realized with atomic-scale precision through the atomic layer deposition technique.Owing to the unique hybrid structure,the FeSiAl@ZnO@Al_(2)O_(3) exhibits record-high micro-wave absorbing performance in low-frequency bands covering L and S bands with a minimum reflection loss(RLmin)of-50.6 dB at 3.4 GHz.Compared with pure FeSiAl(RLmin of-13.5 dB,a bandwidth of 0.5 GHz),the RLmin value and effective bandwidth of this designed novel absorber increased up to~3.7 and~3 times,respectively.Fur-thermore,the inert ceramic dual-shells have improved 9.0 times the anti-corrosion property of FeSiAl core by multistage barriers towards corrosive medium and obstruction of the electric circuit.This is attributed to the large charge transfer resistance,increased impedance modulus|Z|0.01 Hz,and frequency time constant of FeSiAl@ZnO@Al_(2)O_(3).The research demonstrates a promising platform toward the design of next-generation MAs with improved anti-corrosion properties. 展开更多
关键词 Atomic layer deposition Magnetic alloy Dual-oxide-shells Microwave absorption ANTI-CORROSION
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Groups-dependent phosphines as the organic redox for point defects elimination in hybrid perovskite solar cells 被引量:2
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作者 Zhengli Wu Miao Zhang +9 位作者 yifan liu Yuxi Dou Yinjie Kong Lin Gao Weitao Han Guijie Liang Xiao Li Zhang Fuzhi Huang Yi-Bing Cheng Jie Zhong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期23-29,共7页
Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteri... Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteriorate device efficiency,but also facilitate chemical degradation with ion migration,resulting in restricted device lifetime.Herein,we present a novel type of phosphines as the point defects stabilizer for hybrid perovskite solar cells with enhanced performances.Three phosphines with varied side groups of tributyl,trioctyl and triphenyl are exampled as the dopants in perovskite films.The group dependent redox properties were observed in the perovskite film,dependent on their molecular weights and steric hinderances of phosphines.The partially oxidized tributyl phosphine(TBUP)with additional tributyl phosphine oxides(TBPO)is efficient in reduction of lead(Pb)^(0) and iodine(I)^(0) concentrations during the device fabrication and operation.The device with TBUP-TBPO pair showed enhanced power conversion efficiency(PCE)to 20.48% and maintain 91.7% of their initial PCEs after 500 h at 65℃ thermal annealing.Thus,this work presents an efficient route of utilize the phosphine species to reduce point defects in the perovskite film,which promoting further development of novel phosphorous additives with defects stabilization,interface passivation and encapsulation for low-cost solution processed PSCs. 展开更多
关键词 Redox Perovskite solar cells Phosphine organics Lead defect Stability
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Optomechanical soft metamaterials 被引量:1
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作者 Xiangjun Peng Wei He +2 位作者 yifan liu Fengxian Xin Tian Jian Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第3期575-584,共10页
We present a new type of optomechanical soft metamaterials, which is different from conventional mechanical metamaterials, in that they are simple isotropic and homogenous materials without resorting to any complex na... We present a new type of optomechanical soft metamaterials, which is different from conventional mechanical metamaterials, in that they are simple isotropic and homogenous materials without resorting to any complex nano/microstructures. This metamaterial is unique in the sense that its responses to uniaxial forcing can be tailored by programmed laser inputs to manifest different nonlinear constitutive behaviors, such as monotonic, S-shape, plateau, and non-monotonic snapping performance. To demonstrate the novel metamaterial, a thin sheet of soft material impinged by two counterpropagating lasers along its thickness direction and stretched by an in-plane tensile mechanical force is considered. A theoretical model is formulated to characterize the resulting optomechanical behavior of the thin sheet by combining the nonlinear elasticity theory of soft materials and the optical radiation stress theory. The optical radiation stresses predicted by the proposed model are validated by simulations based on the method of finite elements. Programmed optomechanical behaviors are subsequently explored using the validated model under different initial sheet thicknesses and different optical inputs, and the first- and second-order tangential stiffness of the metamaterial are used to plot the phase diagram of its nonlinear constitutive behaviors. The proposed optomechanical soft metamaterial shows great potential in biological medicine, microfluidic manipulation, and other fields. 展开更多
关键词 OPTOMECHANICS Soft metamaterial Optical radiation stress Programmable constitutive relation
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Changes of melatonin and its receptors in synchronizing turbot(Scophthalmus maximus)seasonal reproduction and maturation rhythm 被引量:1
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作者 Chunyan Zhao Shihong Xu +5 位作者 yifan liu Chengcheng Feng Yongshuang Xiao Yanfeng Wang Qinghua liu Jun Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第1期84-98,共15页
In most fish,reproduction is seasonal or periodic under the suitable conditions.In turbot(Scophthalmus maximus)farms,one of the most economically important marine flatfish species,changes in daylength could cause chan... In most fish,reproduction is seasonal or periodic under the suitable conditions.In turbot(Scophthalmus maximus)farms,one of the most economically important marine flatfish species,changes in daylength could cause changes in the spawning time.In this study,to characterize the regulation of reproductive physiology following light signals,three melatonin receptors(Mtnr)investigated in turbot were named sm Mtnr1,sm Mtnr2,and sm Mtnr1 c.Distinct expression profiles demonstrated that Mtnr m RNAs were concentrated in the brain(as detected in the hypothalamus(Hy)and mesencephalon(Me)),gonad and eye.The most abundant Mtnr1 and Mtnr2 m RNA expression levels were detected in the central nervous system at the beginning of the breeding season,suggesting that Mtnr1 and Mtnr2 may play vital roles in the regulation of turbot gonadal development.In addition,the melatonin profiles gradually increased and reached to the highest level at the spawning stage,indicating that melatonin is a potent hormone in the regulation of fish oocyte growth and maturation.The results of this study suggested that melatonin is the primary factor that transduces the light signal and regulates the physiological functions of turbot seasonal reproduction.Moreover,the results of this study may establish a foundation for further research seeking to identify fish melatonin receptors involved in the gonadal development and gamete maturation. 展开更多
关键词 TURBOT brain MELATONIN melatonin receptors seasonal reproductive development
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Influence of shape effect on dynamic surface charge transport mechanism of cellular electret after corona discharge
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作者 Jiawei ZHANG Zelei ZHANG +4 位作者 T MATSUMOTO Qingqing GAO Yuanye liu K NISHIJIMA yifan liu 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第4期82-88,共7页
Surface charge accumulation and transport on cellular polypropylene play an important role in nanogenerators,which could have a potential impact on energy harvesting and wearable devices for zero carbon energy systems... Surface charge accumulation and transport on cellular polypropylene play an important role in nanogenerators,which could have a potential impact on energy harvesting and wearable devices for zero carbon energy systems and the internet of things.Different shapes have different charge accumulation and decay characteristics of the polymer.Therefore,we studied the influence of the sample’s shape on the surface charge decay by experiment and modeling.The surface potential of square and circular cellular polypropylene was measured by a two-dimensional surface potential measurement system with electrostatic capacitive probe.The experimental result shows that the surface potential distribution of the square sample dissipates non-uniformly from the bell shape to a one-sided collapsed shape,while that of the circular sample dissipates uniformly from the bell shape to the crater-like shape.Moreover,the simulated results of the initial surface potential distributions of the square and circular cellular polypropylene are consistent with the experimental results.The investigation demonstrates that the charge transport process is correlated with the shape of the sample,which provides significant reference for designing electret material used for highly efficient nanogenerators. 展开更多
关键词 charge transport NANOGENERATOR corona discharge simulation shape effect cellular polypropylene sustainable energy
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聚丙烯/三聚氰胺泡沫高吸油韧性材料
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作者 戴天 金玄懿 +5 位作者 任强 乔长宇 刘一凡 吴盾 汪称意 李坚 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第2期80-85,共6页
采用聚丙烯甲苯溶液对三聚氰胺泡沫进行浸渍处理得到改性三聚氰胺泡沫材料。傅里叶变换红外光谱和扫描电子显微镜分析表明,聚丙烯成功包覆在三聚氰胺泡沫骨架表面,形成了微纳级凹凸结构。改性泡沫表现出吸油拒水的特点,水接触角均在130&... 采用聚丙烯甲苯溶液对三聚氰胺泡沫进行浸渍处理得到改性三聚氰胺泡沫材料。傅里叶变换红外光谱和扫描电子显微镜分析表明,聚丙烯成功包覆在三聚氰胺泡沫骨架表面,形成了微纳级凹凸结构。改性泡沫表现出吸油拒水的特点,水接触角均在130°以上。改性泡沫材料吸收柴油和多种溶剂的量在45~98 g/g之间,重复吸油100次后的吸油能力保持率在93%以上,表明该材料具有高吸油效率及可重复使用性。拉伸测试表明改性泡沫相对于未改性泡沫的韧性得到提高。该方法工艺简单,原料成本低,容易工业化,为高吸油韧性吸附剂的制备以解决油污染问题提供了一种新的途径。 展开更多
关键词 聚丙烯 三聚氰胺泡沫 油污染 吸附剂 韧性
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