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Novel magnetic silicate composite for lightweight and efficient electromagnetic wave absorption

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Journal of Materials Science & Technology 2021年第33期92卷 51-59页

作者： Di Lan Zehao Zhao Zhenguo Gao Kaichang Kou Hongjing wu MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Northwestern Polytechnical UniversityXi’an 710072China

A series of silicates with double shell hollow sphere morphology were prepared by hydrothermal method with ultra-high temperature calcined,and used in the field of electromagnetic(EM)wave *** characterizing the chemical composition,crystal structure,micro morphology and EM parameters of the several materials,the evaluation results of EM wave absorption capacity of the materials were *** the discussion section,we will discuss the reasons for the differences in EM wave absorption capabilities of the several silicates from multiple aspects such as EM wave absorption mechanism in *** for iron-based silicate(HGMs@Fe_(2)SiO_(4.)materials,after reasonable composition and morphology design,the minimum reflection loss(RLmin)reached up to-4..14.d B with a matching thickness(d)of 3.4.mm,and the corresponding effective absorption bandwidth(f_(E),RL<-10 d B)was 6.80 *** of the wide EM wave absorption bandwidth,light weight and low water absorption,this kind of double shell silicate material has gained huge application potential in the EM wave absorption field.

关键词： Magnetic silicate composite Electromagnetic wave absorption Impendance matching

Crystal structure and enhanced microwave dielectric properties of the Ce_(2)[Zr_(1−x)(Al_(1/2)Ta_(1/2))_(x)]_(3)(MoO_(4.)_(9) ceramics at microwave frequency

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Journal of Advanced Ceramics 2022年第3期11卷 392-402页

作者： Chao FENG Xu ZHOU Bingjing TAO Haitao wu Shifeng HUANG Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials University of JinanJinan250022China School of Environmental and Material Engineering Yantai UniversityYantai264005China

Dense microwave dielectric ceramics of Ce_(2)[Zr_(1−x)(Al_(1/2)Ta_(1/2))_(x)]_(3)(MoO_(4.)_(9)(CZMAT) (x = 0.02–0.10) were prepared by the conventional solid-state route. The effects of (Al1/2Ta1/2)^(4.) on their microstructures, sintering behaviors, and microwave dielectric properties were systematically investigated. On the basis of the X-ray diffraction (XRD) results, all the samples were matched well with Pr_(2)Zr_(3)(MoO_(4.)_(9) structures, which belonged to the space group R3¯c. The lattice parameters were obtained using the Rietveld refinement method. The correlations between the chemical bond parameters and microwave dielectric properties were calculated and analyzed by using the Phillips—Van Vechten—Levine (P—V—L) theory. Excellent dielectric properties of Ce_(2)[Zr_(0.94.(Al_(1/2)Ta_(1/2))_(0.06)]_(3)(MoO_(4.)_(9) with a relative permittivity (ε_(r)) of 10.4., quality factor (Q × f) of 83,796 GHz, and temperature coefficient of resonant frequency (τ_(f)) of −11.50 ppm/℃ were achieved at 850 ℃.

关键词： microwave dielectric ceramics Ce_(2)[Zr_(1−x)(Al_(1/2)Ta_(1/2))_(x)]_(3)(MoO_(4.)_(9)(CZMAT) Phillips-Van Vechten-Levine(P-V-L)theory low sintering temperature

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川西藏东交通廊道区域工程地质条件评价

地质通报 2024年第9期43卷 1650-1662页

作者：杨志华郭长宝吴瑞安张永双李彩虹邵慰慰中国地质科学院地质力学研究所北京100081 自然资源部活动构造与地质安全重点实验室北京100081 中国地质大学(北京) 北京100083 中国地质大学湖北武汉430074

区域工程地质条件是重大工程规划建设地质安全的重要保障。川西藏东交通廊道位于青藏高原东部,穿越世界上地形地貌和地质构造最复杂的地区,区域工程地质环境复杂。响应重大工程规划建设的地质安全需求,以川西藏东交通廊道重大线性工程... 详细信息

区域工程地质条件是重大工程规划建设地质安全的重要保障。川西藏东交通廊道位于青藏高原东部,穿越世界上地形地貌和地质构造最复杂的地区,区域工程地质环境复杂。响应重大工程规划建设的地质安全需求,以川西藏东交通廊道重大线性工程沿线为研究区,在分析区域工程地质环境的基础上,选取9个地质环境因子指标,采用基于GIS的层次分析法,完成了区域工程地质条件评价,将研究区划分为工程地质条件好、较好、中等和差4.等级。结果显示,活动断裂是最不利的工程地质条件因素,其次是地形起伏度和地质灾害易发程度。工程地质条件好的地区远离活动断裂带和深切峡谷,呈块状、条带状分布于活动断裂带及深切峡谷之间。工程地质条件差的地区主要分布于活动断裂带和高山峡谷区,突出表现为距活动断裂较近,尤其是多条断裂相交或近于相交的地区。研究结果能够为川西藏东交通廊道重大工程规划建设地质安全提供科学支撑。

关键词：区域工程地质条件川西藏东交通廊道层次分析法重大工程青藏高原

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外源褪黑素对水培韭菜生长和品质的影响

园艺学报 2024年第4期51卷 847-858页

作者：郝金倩王宝驹佟静刘明池武占会王素娜刘宁河北工程大学园林与生态工程学院河北邯郸056038 北京市农林科学院蔬菜研究所国家蔬菜工程技术研究中心农业农村部华北都市农业重点实验室北京100097 北京市农林科学院蔬菜研究所蔬菜生物育种全国重点实验室北京100097

水培韭菜辛辣风味不足是限制产业发展难题之一,其主要原因是韭菜风味前体物质S–烃基半胱氨酸亚砜[S-alk(en)yl cysteine sulfoxide,CSO]积累不足。为提升水培韭菜风味,以‘791’韭菜为试材,研究含有不同浓度(25、50、75、100、150μmol... 详细信息

水培韭菜辛辣风味不足是限制产业发展难题之一,其主要原因是韭菜风味前体物质S–烃基半胱氨酸亚砜[S-alk(en)yl cysteine sulfoxide,CSO]积累不足。为提升水培韭菜风味,以‘791’韭菜为试材,研究含有不同浓度(25、50、75、100、150μmol·L^(-1))褪黑素的水培营养液对韭菜生长发育和品质的影响。结果表明:水培韭菜的株高、叶宽、叶长、根系活力、单株干(鲜)质量、理论产量等指标随外源褪黑素浓度的增加呈现先上升后下降的趋势,在褪黑素浓度为100μmol·L^(-1)时达到峰值;褪黑素处理显著提高超氧化物歧化酶(SOD)、过氧化物酶(POD)活性,显著降低丙二醛(MDA)和过氧化氢(H_(2)O_(2))含量;75或100μmol·L^(-1)褪黑素处理能有效促进韭菜可溶性糖、可溶性蛋白、维生素C、总黄酮、总酚等营养物质的积累,硝酸盐含量略有增加;褪黑素处理能显著提升韭叶辛辣度,编码CSO合成关键酶基因AtuFMO4.5/6的表达量也显著增加,它们可能与韭叶辛辣风味提高密切关联。综上,外源褪黑素处理有助于提升水培韭菜的产量和品质,75μmol·L^(-1)褪黑素处理能够兼顾韭菜产量、品质和生产成本,实现优质水培韭菜生产。

关键词：水培韭菜褪黑素 S–烃基半胱氨酸亚砜品质风味

牡蛎蛋白酶解条件优化及高活性体外抗凝血类蛋白修饰物制备

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中国食品添加剂 2024年第6期35卷 77-85页

作者：张铁涛武天明杭瑜瑜海南热带海洋学院食品科学与工程学院三亚572022 海南省海洋食品工程技术研究中心三亚572022

选取牡蛎肉为研究对象,以氨基酸态氮的含量和体外凝血因子Xa抑制活性为考核指标,考察木瓜蛋白酶、胃蛋白酶、胰蛋白酶、复合蛋白酶的酶解效果,其中胃蛋白酶对牡蛎的酶解效果最好。采用响应面法分析响应变量(酶添加量、温度、酶解时间)... 详细信息

选取牡蛎肉为研究对象,以氨基酸态氮的含量和体外凝血因子Xa抑制活性为考核指标,考察木瓜蛋白酶、胃蛋白酶、胰蛋白酶、复合蛋白酶的酶解效果,其中胃蛋白酶对牡蛎的酶解效果最好。采用响应面法分析响应变量(酶添加量、温度、酶解时间)之间的交互影响,并确定最佳酶解工艺条件为:酶添加量2.5%、温度37.7℃、酶解时间4.h,氨基酸态氮的含量达到了3.60 g·mL^(-1)。采用超滤膜技术筛选四-六牡蛎肽组分,采用可控酶解技术,在抑制活性较高的牡蛎肽组分C-端,外结合位点结合一定量的天冬氨酸/谷氨酸。通过体外活性试验确定生成的牡蛎类蛋白修饰物具有体外凝血因子Xa抑制活性。

关键词：牡蛎肉酶解抗凝血活性

Full‑Fiber Auxetic‑Interlaced Yarn Sensor for Sign‑Language Translation Glove Assisted by Artificial Neural Network

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Nano-Micro Letters 2022年第8期14卷 269-282页

作者： Ronghui wu Sangjin Seo Liyun Ma Juyeol Bae Taesung Kim Department of Mechanical Engineering Ulsan National Institute of Science and Technology(UNIST)50 UNIST‑GilUlsan 44919Republic of Korea College of Physical Science and Technology Xiamen UniversityXiamen 361005People’s Republic of China

Yarn sensors have shown promising application prospects in wearable electronics owing to their shape adaptability, good flexibility, and weavability. However, it is still a critical challenge to develop simultaneously structure stable, fast response, body conformal, mechanical robust yarn sensor using full microfibers in an industrial-scalable manner. Herein, a full-fiber auxetic-interlaced yarn sensor(AIYS) with negative Poisson’s ratio is designed and fabricated using a continuous, mass-producible, structure-programmable, and low-cost spinning technology. Based on the unique microfiber interlaced architecture, AIYS simultaneously achieves a Poisson’s ratio of-1.5, a robust mechanical property(0.6 c N/dtex), and a fast train-resistance responsiveness(0.025 s), which enhances conformality with the human body and quickly transduce human joint bending and/or stretching into electrical signals. Moreover, AIYS shows good flexibility, washability, weavability, and high repeatability. Furtherly, with the AIYS array, an ultrafast full-letter sign-language translation glove is developed using artificial neural network. The sign-language translation glove achieves an accuracy of 99.8% for all letters of the English alphabet within a short time of 0.25 s. Furthermore, owing to excellent full letter-recognition ability, real-time translation of daily dialogues and complex sentences is also demonstrated. The smart glove exhibits a remarkable potential in eliminating the communication barriers between signers and non-signers.

关键词： Negative Poisson’s ratio yarns Interlaced yarn sensors Smart glove Deep learning Sign-language translation

Leveraging Structured Information from a Passage to Generate Questions

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Tsinghua Science and Technology 2023年第3期28卷 464-474页

作者： Jian Xu Yu Sun Jianhou Gan Mingtao Zhou Di wu Key Laboratory of Educational Informatization for Nationalities Yunnan Normal UniversityKunming 650500China School of Information Science and Technology Yunnan Normal UniversityKunming 650500China Yunnan Key Laboratory of Smart Education Yunnan Normal UniversityKunming 650500China School of Information Engineering Qujing Normal UniversityQujing 655011China

Question Generation(QG)is the task of utilizing Artificial Intelligence(AI)technology to generate questions that can be answered by a span of text within a given *** research on QG in the educational field struggles with two challenges:the mainstream QG models based on seq-to-seq fail to utilize the structured information from the passage;the other is the lack of specialized educational QG *** address the challenges,a specialized QG dataset,reading comprehension dataset from examinations for QG(named RACE4.G),is reconstructed by applying a new answer tagging approach and a data-filtering strategy to the RACE ***,an end-to-end QG model,which can exploit the intra-and inter-sentence information to generate better questions,is *** our model,the encoder utilizes a Gated Recurrent Units(GRU)network,which takes the concatenation of word embedding,answer tagging,and Graph Attention neTworks(GAT)embedding as *** hidden states of the GRU are operated with a gated self-attention to obtain the final passage-answer representation,which will be fed to the *** show that our model outperforms baselines on automatic metrics and human ***,the model improves the baseline by 0.4.,1.32,and 1.34.on BLEU-4.ROUGE-L,and METEOR metrics,respectively,indicating the effectivity and reliability of our *** gap with human expectations also reflects the research potential.

关键词： automatic Question Generation(QG) RACE4.G dataset Answer-Oriented GAT(AO-GAT) attention mechanism structured information

萝卜硫素治疗孤独症谱系障碍的代谢组学机制研究

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中华精神科杂志 2024年第6期57卷 337-344页

作者：戴思侯艳婷林晶晶沈屹东程道猛吴仁容欧建君中南大学湘雅二医院精神科、国家精神疾病医学中心、国家精神心理疾病临床医学研究中心长沙410011 广州医科大学附属脑科医院(广州市惠爱医院) 广州510370

目的:探索萝卜硫素治疗孤独症谱系障碍(autism spectrum disorder,ASD)的分子机制以及与疗效相关的代谢组学标志物并构建疗效预测模型。方法:纳入2016年8月至2019年5月就诊于中南大学湘雅二医院和广州市惠爱医院的ASD患儿4.例。采用随... 详细信息

目的:探索萝卜硫素治疗孤独症谱系障碍(autism spectrum disorder,ASD)的分子机制以及与疗效相关的代谢组学标志物并构建疗效预测模型。方法:纳入2016年8月至2019年5月就诊于中南大学湘雅二医院和广州市惠爱医院的ASD患儿4.例。采用随机数字表法将患儿分为萝卜硫素治疗组(n=26)和安慰剂组(n=14.。采用OSU孤独症评定量表-DSM-Ⅳ(OSU Autism Rating Scale-DSM-Ⅳ,OARS-4.评估ASD患儿在基线、治疗第4.8和12周的临床症状变化,利用广义线性混合模型比较OARS-4.分在组别和时间上的差异。采集ASD患儿治疗前后的血浆样本,利用超高效液相色谱-高分辨质谱法进行非靶向代谢组学的检测,使用方差分析-成分分析筛选差异代谢物,并进行代谢通路分析。通过Spearman相关分析分析与萝卜硫素治疗疗效显著相关的差异代谢物,最后使用Fisher判别分析筛选疗效预测指标。结果:经12周治疗后,萝卜硫素组临床症状改善显著优于安慰剂组(F=14.11,P4.、0.4.1、0.4.4.P4.1~-0.392,均P4.6%(22/26)。结论:萝卜硫素改善ASD相关临床症状的分子机制可能与细胞膜磷脂代谢有关,鞘磷脂(d35∶1)和牛磺酸可能成为预测萝卜硫素治疗ASD疗效的指标。

关键词：孤独性障碍代谢组学生物学标记萝卜硫素

13~17周龄京粉6号蛋鸡微量元素需要量和动态预测模型研究

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动物营养学报 2024年第7期36卷 4316-4328页

作者：米小梅王凌峰程千惠武佳玉安钰许璐镕齐德生华中农业大学动物科学技术学院、动物医学院武汉430070

本试验旨在基于析因法原理,通过饲养试验和比较屠宰试验确定13~17周龄京粉6号蛋鸡微量元素需要量,并建立动态预测模型。试验选用健康且初始体重为(84..4.±28.65)g的13周龄京粉6号蛋鸡198只,随机选取102只,分为6个重复,每个重复17只,用... 详细信息

本试验旨在基于析因法原理,通过饲养试验和比较屠宰试验确定13~17周龄京粉6号蛋鸡微量元素需要量,并建立动态预测模型。试验选用健康且初始体重为(84..4.±28.65)g的13周龄京粉6号蛋鸡198只,随机选取102只,分为6个重复,每个重复17只,用于生长需要的测定;另外96只蛋鸡用于维持需要的测定。维持需要试验根据不同采食量分为100%自由采食组、70%自由采食组和4.%自由采食组,其中100%自由采食组数据与生长需要试验数据共用,70%自由采食组和4.%自由采食组每组6个重复,每个重复8只鸡。试验期5周。结果表明:1)蛋鸡生长曲线为y=1925.600exp-4.34.exp(-0.02 t);体增重与日龄的动态关系为y′=1180.25exp[-4.34.exp(-0.02 t)-0.02]。式中:y表示体增重(g);t表示日龄。2)每只蛋鸡每天铜、铁、锌、锰的生长需要量分别为0.01~0.02 mg/d、0.28~0.4. mg/d、0.21~0.32 mg/d、0.01~0.03 mg/d,维持需求量分别为0.01、0.20、0.08、0.02 mg/d。3)蛋鸡铜、铁、锌、锰需要量与日龄的动态预测模型为:N_(铜)={0.011[1925.600exp-4.34.exp(-0.02 t)]^(0.75)-2.24.exp[-4.34.exp(-0.02 t)-0.02 t]+4.54.exp[-8.694.xp(-0.02 t)-0.02 t]-0.118exp[-4.34.exp(-0.02 t)-0.02 t]+0.4.5exp[-8.694.xp(-0.02 t)-0.02 t]}/ADFI/A;N_(铁)={0.211[1925.600exp-4.34.exp(-0.02 t)]^(0.75)-4..371exp[-4.34.exp(-0.02 t)-0.02 t]+136.361exp[-8.694.xp(-0.02 t)-0.02 t]-22.661exp[-4.34.exp(-0.02 t)-0.02 t]+4..908exp[-8.694.xp(-0.02 t)-0.02 t]}/ADFI/B;N锌={0.084.1925.600exp-4.34.exp(-0.02 t)]^(0.75)+12.74.exp[-4.34.exp(-0.02 t)-0.02 t]+4.54.exp[-8.694.xp(-0.02 t)-0.02 t]-24.785exp[-4.34.exp(-0.02 t)-0.02 t]+4..4.4.xp[-8.694.xp(-0.02 t)-0.02 t]}/ADFI/C;N_(锰)={0.021[1925.600exp-4.34.exp(-0.02 t)]^(0.75)-0.236exp[-4.34.exp(-0.02 t)-0.02 t]+2.273exp[-8.694.xp(-0.02 t)-0.02 t]+0.590exp[-4.34.exp(-0.02 t)-0.02 t]+0.04.exp[-8.694.xp(-0.02 t)-0.02 t]}/ADFI/D。式中:N表示每只蛋鸡每天饲粮中微量元素需要量(mg/kg);t表示日龄;ADFI表示平均日采食量(kg);A、B、C、D分别表示铜、铁、锌、锰的消化率(%)。4.蛋鸡铜、铁、锌、锰需要量与体重的动态预测模型为:N_(铜)=(3.05×10^(-7) LBW^(2)-0.000703 LBW+0.364.+0.011 BW^(0.75))/ADFI/A;N_(铁)=(3.4.10^(-6))LBW^(2)-0.0072 LBW+4.3268+0.211 BW^(0.75))/ADFI/B;N锌=(0.0012 LBW-0.2953+0.084.BW^(0.75))/ADFI/C;N_(锰)=(-1.8×10^(-6) LBW^(2)+0.0039 LBW-1.897+0.021 BW^(0.75))/ADFI/D。式中:N表示每只蛋鸡每天饲粮中微量元素需要量(mg/kg);LBW表示活体重(g);BW^(0.75)表示代谢体重(kg);ADFI表示平均日采食量(kg);A、B、C、D分别表示铜、铁、锌、锰的消化率(%)。综上所述,本试验得出13~17周龄京粉6号蛋鸡铜、铁、锌、锰需求量分别为0.02~0.03 mg/d、0.4.~0.67 mg/d、0.29~0.4. mg/d、0.03~0.05 mg/d,并建立了动态预测模型。

关键词：蛋鸡微量元素需要量动态预测模型