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Young Woman Uses Technology to Improve Agriculture
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作者 Wei Ran 《Women of China》 2026年第1期68-69,共2页
"During the pasp eepede,I have iospired many young people to move to rural areas,to engage in agriculture and help farmers.I hope to root and bloom in the countryside,and to help develop this land full of hope.&q... "During the pasp eepede,I have iospired many young people to move to rural areas,to engage in agriculture and help farmers.I hope to root and bloom in the countryside,and to help develop this land full of hope."Hua Mengli told a news conference,themed Strivers on the New Journey,organized by the State Council Information Office,on May 23,2025.Hua,who was born in 1995 in Zhenjiang,a city in East China's Jiangsu Province,is general manager of Jiangsu Guomubuwang Farm. 展开更多
关键词 rural areas FARMERS development AGRICULTURE news conference strivers technology pasp eepedei
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Tracking a High-Tech Transition--How technology is powering Guangdong’s manufacturing transformation
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作者 HU FAN 《ChinAfrica》 2026年第1期30-32,共3页
The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them w... The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them was not a typical exhibition hall,but a building shaped like a gleaming stainless-steel cooking pot. 展开更多
关键词 othello kitchenware museum technology industrial strength high tech transition guangdong manufacturing transformation
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Between Themis and Prometheus:a history of the ethics of science and technology
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作者 Jia-Yun Chen Zong-Zhen Wu +7 位作者 Qiang-Yu Xiang Lu Zhang Jia-Lin Diao Ya-Hui Zhang Shen-Shen Yan Kun-Lan Zuo Jian-Liang Huang Huan Liu 《History and Philosophy of Medicine》 2026年第1期49-59,共11页
Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide ... Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide technology for good and prevent and control technological risks has become an important issue of global concern.Research on science and technology ethics is dedicated to integrating ethical theories into governance practices and constructing ethical models that adapt to the development of the times.Methods:This article systematically reviews the six core approaches of scientific and technological ethics thought,including technological autonomy and political philosophy criticism,responsibility ethics and intergenerational obligations,technological intermediation and the integration of life and the world,ethical principles and normative frameworks,participatory governance and ethical practice innovation,as well as domain-specific ethical norms,thereby constructing an ethical analysis framework applicable to medical technology risks.And cross-analysis was conducted by taking medical events such as gene editing and xenotransplantation as examples.Results:Research shows that a single ethical approach has limitations in addressing complex medical ethical challenges,while the six approaches are complementary and synergistic.By criticizing technological autonomy,establishing a responsibility ethics orientation,setting the bottom line of ethical principles,promoting participatory governance,formulating domain norms,and continuously reflecting on the intermediary nature of technology,a multi-level and dynamically adaptive governance system for scientific and technological ethics can be constructed.Conclusion:The key to addressing contemporary medical ethics challenges lies in the comprehensive application of science and technology ethics theories and the integration of ethical considerations throughout the entire process of scientific and technological research and development.In the future,a governance framework that adapts to the development of new technologies should be established to promote cross-cultural and cross-disciplinary ethical dialogue and public participation,ensuring that scientific and technological innovation always serves the dignity of human life and overall well-being. 展开更多
关键词 ethics of science and technology history of science ethical governance responsible innovation medical ethics
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Low-temperature bonding of W90 tungsten heavy alloy using Sn−2Al filler metal by ultrasonic-assisted coating technology
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作者 Xiao-guo SONG Xu-dong ZHANG +3 位作者 Wei FU Xiao-yu TIAN Guang-dong WU Sheng-peng HU 《Transactions of Nonferrous Metals Society of China》 2026年第1期259-272,共14页
The Sn−2Al filler metal was utilized to bond W90 tungsten heavy alloys by the ultrasonic-assisted coating technology in atmospheric environment at 250℃.The effects of ultrasonic power and ultrasonic time on microstru... The Sn−2Al filler metal was utilized to bond W90 tungsten heavy alloys by the ultrasonic-assisted coating technology in atmospheric environment at 250℃.The effects of ultrasonic power and ultrasonic time on microstructure and interfacial strength of Sn−2Al/W90 interface were investigated.The ultrasound improved the wettability of Sn−2Al filler metal on W90 surface.As the ultrasonic power increased and ultrasonic time increased,the size of Al phase in seam decreased.The maximum value of Sn−2Al/W90 interfacial strength reached 30.1 MPa.Based on the acoustic pressure simulation and bubble dynamics,the intensity of cavitation effect was proportional to ultrasonic power.The generated high temperature and high pressure by cavitation effect reached 83799.6 K and 1.26×10^(14) Pa,respectively. 展开更多
关键词 W−Ni−Fe alloy Sn−Al filler metal ultrasonic-assisted coating technology acoustic pressure CAVITATION bubble dynamics
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基于HS-SPME-GC-MS技术的6种香型白酒中挥发性化合物差异分析
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作者 胡晓龙 李华 +5 位作者 雷旭东 韩素娜 张俊飞 邓鸣东 黄润娜 王晓毅 《轻工学报》 北大核心 2026年第1期1-15,共15页
【目的】进一步明晰4种基本香型和2种融合香型白酒挥发性化合物特征、关键香气及差异成分。【方法】采用顶空-固相微萃取-气相色谱-质谱联用(HS-SPME-GC-MS)技术、相对气味活度值(ROAV)法及正交偏最小二乘判别分析(OPLS-DA)法,对4种基... 【目的】进一步明晰4种基本香型和2种融合香型白酒挥发性化合物特征、关键香气及差异成分。【方法】采用顶空-固相微萃取-气相色谱-质谱联用(HS-SPME-GC-MS)技术、相对气味活度值(ROAV)法及正交偏最小二乘判别分析(OPLS-DA)法,对4种基本香型和2种融合香型白酒的挥发性化合物分布特征、关键香气成分及重要差异化合物进行分析。【结果】6种香型白酒中共鉴定出207种挥发性化合物,涵盖10个类别,主要为酯类、芳香族类、醇类、烯类、醛类和酮类化合物,且各香型白酒中的挥发性化合物组成差异明显,其中存在于所有香型、单一香型及2~5种香型白酒中的挥发性化合物分别为26种、77种及104种;清香型和米香型白酒中的挥发性化合物种类较少;陶融香型和兼香型白酒在挥发性化合物组成上均与浓香型和酱香型白酒更为相似。此外,己酸乙酯、辛酸乙酯、苯乙酸乙酯等10种挥发性化合物为1种或多种香型白酒的关键香气化合物;己酸乙酯、十四酸乙酯、十六酸乙酯、乙酸乙酯等13种挥发性化合物为区分6种香型白酒的重要差异挥发性化合物。【结论】不同香型白酒挥发性化合物组成存在明显差异,其关键香气化合物与差异化合物均以乙酯类为主,基本香型白酒工艺的科学融合是研制创新香型白酒的重要技术路径。 展开更多
关键词 白酒香型 顶空-固相微萃取-气相色谱-质谱联用技术 挥发性化合物 差异分析
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HS-SPME-GC-MS结合ROAV分析不同包装材料对乳粉品质的影响 被引量:2
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作者 张钰欣 昝成顺 +6 位作者 贺凯茹 王海斌 刘迎雪 宁淼 乌日娜 张淑丽 武俊瑞 《食品工业科技》 北大核心 2025年第9期243-252,共10页
为探究包装材料差异对于乳粉品质的影响,本研究选取使用三种常见包装材料的乳粉(普通塑料包装-聚丙烯(polypropylene,PP),高阻隔材料包装-聚乙烯/聚乙烯醇/聚乙烯(polyethylene/polyvinyl alcohol/polyethylene,PE/PVA/PE),铝塑包装-聚... 为探究包装材料差异对于乳粉品质的影响,本研究选取使用三种常见包装材料的乳粉(普通塑料包装-聚丙烯(polypropylene,PP),高阻隔材料包装-聚乙烯/聚乙烯醇/聚乙烯(polyethylene/polyvinyl alcohol/polyethylene,PE/PVA/PE),铝塑包装-聚酯/聚酰胺/铝箔/聚乙烯(polyethylene terephthalate/polyamide/aluminum foil/polyethylene,PET/PA/AL/PE)),对其多种理化指标及挥发性风味物质进行测定。基于顶空固相微萃取-气相色谱-质谱联用法(headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)测定挥发性物质组成,结合相对气味活度值法(relative odor activity value,ROAV)鉴定关键风味化合物。结果表明,高阻隔及铝塑包装维持乳粉原有理化性质(水分含量、溶解度、粒径、色泽及脂肪含量)的能力较强。GC-MS检出所有样品共有53种挥发性物质。对比其他类型包装,普通塑料包装乳粉中脂肪氧化程度高致使其酸类物质相对含量上升,油酸发生较大程度氧化及产生正癸酸,致使乳粉出现酸腐味。高阻隔及铝塑包装可有效抑制糠醛、5-羟甲基糠醛、2(5H)-呋喃酮、糠醇及麦芽酚等于热加工阶段产生的挥发性物质释放,这些物质赋予乳粉焦糖香及黄油香等积极气味。普通包装气密性差造成储存过程中风味物质大量逸散,使乳粉风味单一及乳味淡薄。经ROAV分析可知所有样品共有24种挥发性组分贡献香气,铝塑(14、15种)包装乳粉相较于普通(12种)及高阻隔(各13种)包装乳粉所含正向香气物质种类更为丰富。本研究为企业选择合适的包装工艺,改善乳粉风味,提高其营养价值和质量安全水平,提供一定的参考。 展开更多
关键词 包装材料 乳粉 理化指标 挥发性风味物质 hs-spme-gc-ms ROAV
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基于HS-SPME-GC-MS与感官评价的太子参特异性气味物质基础研究 被引量:2
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作者 冯佳敏 李师瑶 +5 位作者 游润秋 包晓明 陈心铭 黄浩洲 郑川 张定堃 《中草药》 北大核心 2025年第15期5596-5604,共9页
目的通过挥发性成分分析结合志愿者感官评价,探究构成太子参Pseudostellaria heterophylla特异性气味物质基础。方法采用固相微萃取-气相色谱-质谱联用技术(headspace solid-phase microextraction-gas chromatography-mass spectrometr... 目的通过挥发性成分分析结合志愿者感官评价,探究构成太子参Pseudostellaria heterophylla特异性气味物质基础。方法采用固相微萃取-气相色谱-质谱联用技术(headspace solid-phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)对10批太子参药材挥发性成分进行检测分析,通过气味活度值(odor activity value,OAV)和化合物气味描述初步确定太子参特异性气味的物质基础。将特异性气味成分的OAV值与志愿者感官评价进行Spearman相关性分析,以明确太子参特异性气味的物质基础。结果研究表明,太子参药材具有土霉味、酸味、脂肪味等特殊气味,其中OAV>100的关键物质包括己酸、2-乙基-3,5-甲基吡嗪、(E)-2-壬醛、1-辛烯-3-酮、(E,E)-2,4-壬二烯醛、2,3-丁二酮。Spearman双变量相关性分析结果表明,土霉味与2-乙基-3,5-甲基吡嗪、1-辛烯-3-醇、(E)-2-壬醛呈显著正相关;酸味与辛酸、己酸、正戊酸呈显著正相关;脂肪味与(E,E)-2,4-壬二烯醛、壬醛、(E)-2-十一烯醛、(E)-2-辛烯醛呈显著正相关。结论不仅识别了太子参气味的主要贡献成分,还明确了不同气味特征与化学成分之间的对应关系,为太子参矫味相关研究提供了重要的数据支撑。 展开更多
关键词 太子参 hs-spme-gc-ms Spearman相关性 土霉味 酸味 脂肪味
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基于HS-GC-IMS、HS-SPME-GC-MS和UPLC-Q-Orbitrap-MS结合化学计量学探讨当归酒炙前后化学成分差异
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作者 孙雪豪 陈家璇 +5 位作者 尹佳鑫 韩潇 窦志英 李正 康利平 余河水 《中国中药杂志》 北大核心 2025年第14期3909-3917,共9页
基于顶空-气相色谱-离子迁移质谱(HS-GC-IMS)、顶空-固相微萃取-气相色谱-质谱(HS-SPME-GC-MS)和超高效液相色谱-四极杆-静电场轨道阱-质谱(UPLC-Q-Orbitrap-MS)技术结合化学计量学探讨当归在酒炙过程中物质基础变化的内涵。构建当归和... 基于顶空-气相色谱-离子迁移质谱(HS-GC-IMS)、顶空-固相微萃取-气相色谱-质谱(HS-SPME-GC-MS)和超高效液相色谱-四极杆-静电场轨道阱-质谱(UPLC-Q-Orbitrap-MS)技术结合化学计量学探讨当归在酒炙过程中物质基础变化的内涵。构建当归和酒当归的HS-GC-IMS指纹图谱,统计当归炮制前后各类挥发性成分的变化趋势并对其挥发性小分子物质进行表征。运用主成分分析(PCA)和正交偏最小二乘判别分析(OPLS-DA)进行区分和差异性分析。基于HS-GC-IMS技术从当归中鉴定出89种挥发性成分,包括14种不饱和烃类化合物、16种醛类、13种酮类、9种醇类、16种酯类、6种有机酸类和15种其他成分。利用HS-SPME-GC-MS技术鉴定出118种挥发性成分,包括42种不饱和烃类化合物、11种芳香类、30种醇类、8种烷类、6种有机酸类、4种酮类、7种醛类、5种酯类和5种其他挥发性成分。采用UPLC-Q-Orbitrap-MS技术鉴定出非挥发性物质76种。主成分分析显示3种技术下的当归和酒当归聚类明显,PCA和OPLS-DA可以区分当归和酒当归,同时发现VIP>1的化合物共145种可作为判断当归炮制质量的关键因子,如HS-GC-IMS定性出的4-甲基-3-戊烯-2-酮、2-甲基戊酸乙酯和2,4-二甲基-1,3-二氧戊环等化合物,HS-SPME-GC-MS定性出的当归酸、β-蒎烯和大根香叶烯B等化合物,UPLC-Q-Orbitrap-MS定性出的L-色氨酸、甘草利酮和川白芷素等化合物。综上,3种分析方法结合化学计量学可评价当归和酒当归化学成分物质基础差异性,为酒当归的炮制机制研究和临床应用提供参考。 展开更多
关键词 当归 酒当归 HS-GC-IMS hs-spme-gc-ms UPLC-Q-Orbitrap-MS 主成分分析
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基于HS-SPME-GC-MS解析川红工夫红茶关键香气成分及形成机理 被引量:1
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作者 杨植溢 练学燕 +1 位作者 金磊 李东 《食品工业科技》 北大核心 2025年第17期47-55,共9页
为分析川红工夫红茶的关键香气成分及在加工过程中的形成规律,基于感官组学、顶空固相微萃取结合气相色谱-质谱联用(Head space-solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GCMS)、电子鼻(Electronic n... 为分析川红工夫红茶的关键香气成分及在加工过程中的形成规律,基于感官组学、顶空固相微萃取结合气相色谱-质谱联用(Head space-solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GCMS)、电子鼻(Electronic nose,E-nose)等分子感官技术解析由‘天府5号’茶树鲜叶加工制作的川红工夫红茶香气成分,并进行了主成分分析(Principal component analysis,PCA)与偏最小二乘法判别分析(Partial least squares-discriminant analysis,PLS-DA)及其置换检验,最后通过气味活度值(Odor activity value,OAV)筛选出关键香气成分,并对其形成进行了初步探究。结果表明,川红工夫红茶在不同加工阶段的香气成分不同,随着加工的进行,茶样香气强度逐渐加强,烘干后的茶样具有较强的花果香和甜香;共鉴定出52种挥发性代谢物,醇类、酯类和醛类化合物是川红工夫红茶的主要呈香物质;其中,筛选出16种香气成分(OAV≥1),香叶醇、芳樟醇和β-紫罗兰酮是关键香气成分(OAV≥100),揉捻过程会提高芳樟醇和香叶醇的含量;发酵过程中生成了β-紫罗兰酮,香叶醇含量升高,芳樟醇含量降低。研究阐明了川红工夫红茶加工过程中香气成分及变化规律,为以川红工夫红茶品质控制和提升提供一定的科学依据。 展开更多
关键词 川红工夫红茶 hs-spme-gc-ms OAV 关键香气成分 形成机理
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基于HS-SPME-GC-MS技术对甜面酱的风味代谢调控
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作者 袁柳凤 耿丽华 +3 位作者 王朔 何静 聂煜冬 王春玲 《中国调味品》 北大核心 2025年第11期31-37,共7页
文章以发酵甜面酱为研究对象,使用HS-SPME-GC-MS技术对不同发酵温度、料液比、盐水浓度下甜面酱的挥发性风味物质进行检测,采用PLS-DA法分析不同发酵条件下甜面酱的风味差异。研究结果表明,发酵温度对甜面酱中醛类、醇类、酯类物质的影... 文章以发酵甜面酱为研究对象,使用HS-SPME-GC-MS技术对不同发酵温度、料液比、盐水浓度下甜面酱的挥发性风味物质进行检测,采用PLS-DA法分析不同发酵条件下甜面酱的风味差异。研究结果表明,发酵温度对甜面酱中醛类、醇类、酯类物质的影响显著,发酵温度升高对醛类物质的影响最大,发酵温度为先45℃后38℃时,甜面酱中挥发性风味物质较丰富,醛类含量最高,其焦糖香、酱香更浓郁。不同料液比对甜面酱中醛类、醇类物质的影响较大,料液比过小会使挥发性风味物质的种类和含量降低,当料液比为1∶1~1∶1.2时,醇类物质含量较高,醇香、果香较明显。不同盐水浓度对醇类、醛类物质的影响显著,盐水浓度较低时,更利于醇类物质的产生,而盐水浓度较高时,甜面酱的挥发性风味物质种类减少,当盐水浓度为12%时,甜面酱中的挥发性风味物质种类更丰富,含量较高,其酱香更突出。该研究结果揭示了不同发酵条件下甜面酱挥发性风味物质及关键特征香气的差异,为后续基于风味组成对发酵甜面酱的风味和品质进行调控提供了理论依据。 展开更多
关键词 甜面酱 hs-spme-gc-ms PLS-DA 挥发性风味物质 感官评价
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HS-SPME-GC-MS技术结合ROAV分析桐柏山野红茶的关键香气物质
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作者 郭俊齐 王亚菲 +5 位作者 沈瑜 夏瑶 贾子璐 黄钲荃 李梦茹 赵仁亮 《南方农业学报》 北大核心 2025年第10期3081-3092,共12页
【目的】揭示桐柏山野红茶与常规栽培红茶在相同加工工艺条件下挥发性成分的差异,并明确其特征香气物质,以期为桐柏地区野放茶树资源的高效开发利用及桐柏红茶香气品质的优化提供参考依据。【方法】选取桐柏县2种野放茶树和4种常规栽培... 【目的】揭示桐柏山野红茶与常规栽培红茶在相同加工工艺条件下挥发性成分的差异,并明确其特征香气物质,以期为桐柏地区野放茶树资源的高效开发利用及桐柏红茶香气品质的优化提供参考依据。【方法】选取桐柏县2种野放茶树和4种常规栽培茶树的1芽2叶鲜叶为原料,按照相同工艺加工制作6个桐柏红茶样品,采用顶空固相微萃取—气相色谱—质谱联用(HS-SPME-GC-MS)技术对其挥发性成分组成进行解析,并鉴定其关键香气物质。【结果】从6个桐柏红茶样品中共鉴定出115种挥发性成分,涵盖酯类(38种)、醇类(16种)、醛类(20种)、酮类(15种)、萜烯类(9种)、杂环类(7种)、酸类(6种)、苯酚类(3种)和其他类(1种)。对比发现,山野红茶(94种)的挥发性成分相较于常规栽培红茶(89种)更为丰富,但其相对含量低于常规栽培红茶。基于多元统计分析筛选鉴定出32种关键差异化合物[变量投影重要性(VIP)>1、P<0.05],通过计算各化合物的相对气味活度值(ROAV)明确正己醛、(E)-3,7-二甲基-2,6-辛二烯醛、丙位壬内酯等16种气味活性化合物是造成山野红茶与常规栽培红茶香气品质差异的关键香气活性物质(ROAV>1)。其中,甲基庚烯酮(脂香、青香、柑橘气味,最高ROAV=103.13)和丙位壬内酯(椰子香,最高ROAV=562.80)是常规栽培红茶中贡献较大的气味活性物质;正己醛(果香、青香,最高ROAV=6785.00)、(E)-3,7-二甲基-2,6-辛二烯醛(柠檬香,最高ROAV=1175.43)和庚醛(果香、脂香,最高ROAV=232.53)是山野红茶中贡献较大的气味活性物质。【结论】茶树受生长环境影响,桐柏山野红茶和常规栽培红茶挥发性成分及相对含量存在一定差异;山野红茶的重要香气贡献物质多于常规栽培红茶,贡献度更大,呈花香、甜香、果香等香型,香气质量更优,开发潜力大。 展开更多
关键词 桐柏山野红茶 常规栽培红茶 挥发性成分 相对气味活度值(ROAV) hs-spme-gc-ms
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A new horizon for neuroscience:terahertz biotechnology in brain research 被引量:1
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作者 Zhengping Pu Yu Wu +2 位作者 Zhongjie Zhu Hongwei Zhao Donghong Cui 《Neural Regeneration Research》 SCIE CAS 2025年第2期309-325,共17页
Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biot... Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biotechnology and its applications in the field of neuropsychiatry.Available evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin deficit.In vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric diseases.Although the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic applications.However,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical applications.This review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages. 展开更多
关键词 biological effect brain NEURON NEUROPSYCHIATRY NEUROSCIENCE non-thermal effect terahertz imaging terahertz radiation terahertz spectroscopy terahertz technology
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澳大利亚教材Design and Technology的特色与启示
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作者 王振强 何善亮 《湖北教育》 2025年第7期84-87,共4页
随着经济一体化和全球化进程的不断推进,世界各国目前都认识到技术与工程教育对于提升综合国力的重要性。基础教育阶段虽不以直接培养各领域的工程师或设计师为目标,但关注学生技术与工程素养的提升,让他们像工程师或设计师一样思考和... 随着经济一体化和全球化进程的不断推进,世界各国目前都认识到技术与工程教育对于提升综合国力的重要性。基础教育阶段虽不以直接培养各领域的工程师或设计师为目标,但关注学生技术与工程素养的提升,让他们像工程师或设计师一样思考和解决问题,这不仅不能回避,而且是亟须直面的问题。《义务教育科学课程标准(2022年版)》的颁布为中小学技术与工程教育的落实指明了方向。 展开更多
关键词 澳大利亚教材 Design and technology
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基于HS-SPME-GC-MS和OAV分析西藏不同地区牦牛乳拉拉关键呈香物质 被引量:1
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作者 董闯 续辉 +1 位作者 祝亚辉 杨林 《食品工业科技》 北大核心 2025年第10期281-290,共10页
以西藏四个地区牦牛乳拉拉为研究对象,采用顶空固相微萃取结合气相色谱-质谱(Headspace-Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry,HS-SPME-GC-MS)联用技术,通过香气活度值(Odor Activity Value,OAV)找出关键... 以西藏四个地区牦牛乳拉拉为研究对象,采用顶空固相微萃取结合气相色谱-质谱(Headspace-Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry,HS-SPME-GC-MS)联用技术,通过香气活度值(Odor Activity Value,OAV)找出关键呈香物质,并运用偏最小二乘判别分析(Partial Least Squares Discriminant Analysis,OPLS-DA),探究不同地区拉拉的关键香气和差异成分,旨在解析西藏地区牦牛乳拉拉的关键呈香物质。结果表明:四个地区牦牛乳拉拉共检测出88种挥发性成分,主要为酸类、醇类、醛类、酯类和酮类以及芳香族化合物;利用阈值筛选出29种OAV≥1的挥发性成分;结合OAV≥1且投影变量影响分析(Impact Analysis of Projection Variables,VIP)>1进一步筛选出9种特征挥发性物质为四个地区牦牛乳拉拉风味的差异性标志物,分别为2R,3R-丁二醇、壬酮、丁二醇、异戊酸、N-甲基-2-吡咯甲醛、乙酸、异丁酸、麦芽酚和肉豆蔻酸。通过OAV、聚类热图、OPLS-DA表明:不同海拔高度的牦牛乳拉拉关键香气成分存在差异,根据VIP筛选出的9种特征挥发性物质较好地区分了四个地区拉拉的特征风味;9种风味物质中2R,3R-丁二醇、壬酮、丁二醇、N-甲基-2-吡咯甲醛、乙酸分别赋予DXLL香甜、青草、烤坚果和淡淡的酸甜味;异戊酸、乙酸、麦芽酚和肉豆蔻酸分别赋予DLLL特殊酸味、焦奶油和椰子香味;异戊酸、异丁酸赋予BGLL酸味。本研究揭示了牦牛乳拉拉关键呈香物质组成,为牦牛乳拉拉特征香气形成机理提供数据支撑,同时也为牦牛乳拉拉的工业化生产提供理论指导。 展开更多
关键词 拉拉 顶空固相微萃取-气相色谱-质谱(hs-spme-gc-ms) 香气活度值(OAV) 偏最小二乘判别分析(OPLS-DA)
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Research progress of intelligent testing technology and evaluation methods for subgrade engineering 被引量:1
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作者 Guojun Cai Hongliang Tian +2 位作者 Lulu Liu Xiaoyan Liu Songyu Liu 《Journal of Road Engineering》 2025年第2期164-183,共20页
Subgrade engineering is a fundamental aspect of infrastructure construction in China.As the primary structural element responsible for bearing and distributing traffic loads,the subgrade must not only withstand the su... Subgrade engineering is a fundamental aspect of infrastructure construction in China.As the primary structural element responsible for bearing and distributing traffic loads,the subgrade must not only withstand the substantial pressures exerted by vehicles,trains,and other forms of transportation,but also efficiently transfer these loads to the underlying foundation,ensuring the stability and longevity of the roadway.In recent years,advancements in subgrade engineering technology have propelled the industry towards smarter,greener,and more sustainable practices,particularly in the areas of intelligent monitoring,disaster management,and innovative construction methods.This paper reviews the application and methodologies of intelligent testing equipment,including cone penetration testing(CPT)devices,soil resistivity testers,and intelligent rebound testers,in subgrade engineering.It examines the operating principles,advantages,limitations,and application ranges of these tools in subgrade testing.Additionally,the paper evaluates the practical use of advanced equipment from both domestic and international perspectives,addressing the challenges encountered by various instruments in realworld applications.These devices enable precise,comprehensive testing and evaluation of subgrade conditions at different stages,providing real-time data analysis and intelligent early warnings.This supports effective subgrade health management and maintenance.As intelligent technologies continue to evolve and integrate,these tools will increasingly enhance the accuracy,efficiency,and sustainability of subgrade monitoring. 展开更多
关键词 Subgrade engineering Intelligent testing technology technology evaluation Health management and maintenance
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电子感官技术结合HS-SPME-GC-MS分析芝麻馕关键挥发性物质
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作者 毛红艳 祖力皮牙·买买提 +2 位作者 王佳敏 岳丽 于明 《新疆农业科学》 北大核心 2025年第7期1803-1811,共9页
【目的】研究芝麻馕的挥发性成分,为馕工业标准化生产化提供理论依据。【方法】利用电子鼻、电子舌、顶空-固相微萃取-气相色谱-质谱(Headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)联用... 【目的】研究芝麻馕的挥发性成分,为馕工业标准化生产化提供理论依据。【方法】利用电子鼻、电子舌、顶空-固相微萃取-气相色谱-质谱(Headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)联用技术,结合相对气味活度值(Relative odor activity value,ROAV)分析新疆芝麻馕中的挥发性成分以及关键香气。【结果】电子鼻可以对不同芝麻馕中的挥发性成分进行有效区分;电子舌对不同芝麻馕中的滋味区分效果不明显。HS-SPME-GC-MS共鉴定出161种化合物,其中包括烷烃40种、烯烃8种、炔烃3种,醛类19种、醇类29种、酮类15种、酯类15种和酸类8种,吡嗪12种、其他化合物12种,其中共有挥发性风味物质41种。(E)-壬烯醛、(E,E)-2,4-癸二烯醛为芝麻馕关键性挥发性物质,庚醛、壬醛、3-甲硫基丙醛、苯乙醛、3-羟基-2-丁酮、异戊醇、正己醇、庚醇对芝麻馕风味具有重要修饰作用。【结论】GC-MS技术结合电子鼻和电子舌为主食芝麻馕的挥发性特征物质分析提供技术支撑。 展开更多
关键词 电子鼻 电子舌 hs-spme-gc-ms ROAV
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Application of AI technology in pulsar candidate identification 被引量:1
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作者 Wanqiong Wang Jie Wang +7 位作者 Xinchen Ye Yazhou Zhang Jia Li Xu Du Wenna Cai Han Wu Ting Zhang Yuyue Jiao 《Astronomical Techniques and Instruments》 2025年第1期27-43,共17页
As artificial intelligence(AI)technology has continued to develop,its efficient data processing and pattern recognition capabilities have significantly improved the precision and speed of decision-making processes,and... As artificial intelligence(AI)technology has continued to develop,its efficient data processing and pattern recognition capabilities have significantly improved the precision and speed of decision-making processes,and it has been widely applied across various fields.In the field of astronomy,AI techniques have demonstrated unique advantages,particularly in the identification of pulsars and their candidates.AI is able to address the challenges of pulsar celestial body identification and classification because of its accuracy and efficiency.This paper systematically surveys commonly used AI models for pulsar candidate identification,analyzing and discussing the typical applications of machine learning,artificial neural networks,convolutional neural networks,and generative adversarial networks in candidate identification.Furthermore,it explores how th.e introduction of AI techniques not only enhances the efficiency and accuracy of pulsar identification but also provides new perspectives and tools for pulsar survey data processing,thus playing a significant role in advancing pulsar research and the field of astronomy. 展开更多
关键词 AI technology Candidate identification Machine learning Neural networks
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Research on Offensive-Defensive Technology System and Key Technologies of Navigation Warfare 被引量:1
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作者 WANG Jian FU Jing +2 位作者 LONG Ke CHANG Xinuo LIU Jiaxing 《Aerospace China》 2025年第1期9-13,共5页
As the core information infrastructure of modern information warfare,the offensive and defensive confrontations of satellite navigation systems have given rise to navigation warfare,which focuses on seizing control of... As the core information infrastructure of modern information warfare,the offensive and defensive confrontations of satellite navigation systems have given rise to navigation warfare,which focuses on seizing control of navigation resources.Based on the space segment,control segment,and user segment of satellite navigation systems,this paper systematically constructs an offensive-defensive technology system for navigation warfare,and deeply analyzes core measures such as signal enhancement and suppression,autonomous navigation and link jamming,anti-jamming reception,and integrated navigation.It extracts key technologies including adaptive nulling antennas,joint filtering,and multi-dimensional combined jamming,and discusses the technical effectiveness of these technologies by incorporating relevant cases.The advantages of navigation warfare stem from multi-segment coordination and technological inte-gration.In the future,the development directions of navigation warfare will focus on three aspects:enhancing satellite capabilities,tackling core technical challenges,and building a multi-dimensional system. 展开更多
关键词 navigation warfare satellite navigation offensive-defensive technology ANTI-JAMMING integrated navigation
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Value realization of intelligent emergency management:research framework from technology enabling to value creation 被引量:1
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作者 Yan Guo Yan Song Mingyue Zhang 《Data Science and Management》 2025年第1期11-22,共12页
This study investigated the application and the application value of intelligent emergency in emergency management in the big data environment.It addresses the neglect of the application value(performance)measurement ... This study investigated the application and the application value of intelligent emergency in emergency management in the big data environment.It addresses the neglect of the application value(performance)measurement of intelligent emergency,further improving the effectiveness of intelligent emergency management.First,approximately 3,900 documents from the intelligent emergency field are analyzed to determine the future research trend in intelligent emergency management.The socio-technical theory concerning technical and social systems is introduced.The emergency management system concepts of“technology enabling”and“enabling value creation”are defined according to bibliometric analysis and socio-technical theory.Second,a research framework that includes technology enabling and enabling value creation for the decision-making paradigm in emergency management according to the big data environment is constructed.A detailed analysis approach from intelligent emergency technology enabling to enabling value creation in emergency management is proposed.Finally,earthquake disasters are taken as examples,and specific analyses of the intelligent emergency enabling and enabling value creation are explored;enabling value creation is discussed based on measurable indicators.The clear concept of emergency management system technology enabling and enabling value creation,as well as the detailed analysis approach from intelligent emergency technology enabling to enabling value creation,provide a theoretical bases for scholars and practitioners to evaluate the value(performance)of intelligent emergency for the first time. 展开更多
关键词 technology enabling Enabling value creation EMERGENCIES Intelligent emergency management
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Deformation mechanism and treatment technology research of coal pillars in acute inclined goafs under expressway 被引量:1
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作者 Bao Wei-Xing Ma Zhi-Wei +1 位作者 Lai Hong-Peng Chen Rui 《Applied Geophysics》 2025年第1期161-175,235,共16页
When the expressway crosses the goafs inevitably,the design is generally to build the road on coal pillars as much as possible.However,the existing coal pillars are often unable to meet relevant requirements of highwa... When the expressway crosses the goafs inevitably,the design is generally to build the road on coal pillars as much as possible.However,the existing coal pillars are often unable to meet relevant requirements of highway construction.Combining three-dimensional physical model tests,numerical simulations and field monitoring,with the Urumqi East Second Ring Road passing through acute inclined goafs as a background,the deformation and failure mechanism of the overlying rock and coal pillars in acute inclined goafs under expressway load were studied.And in accordance with construction requirements of subgrade,comprehensive consideration of the deformation and instability mechanism of acute inclined goafs,the treatment measures and suggestions for this type of geological disasters were put forward.The research results confirmed the rationality of coal pillars in acute inclined goafs under the expressway through grouting.According to the ratio of diff erent overlying rock thickness to coal pillar height,the change trend and value of the required grouting range were summarized,which can provide reference for similar projects. 展开更多
关键词 model test acute inclined goafs SUBGRADE deformation mechanism treatment technology
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