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Research 2024年第2期2023卷 691-702页

作者： Zhongjie Li Chao Yang Qin Zhang Geng Chen jingyuan xu Yan Peng Hengyu Guo School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444P.R.China Institute of Artificial Intelligence Shanghai UniversityShanghai 200444P.R.China National Engineering Research Center of Turbo-Generator Vibration School of Energy and EnvironmentSoutheast UniversityNanjing 210096P.R.China institute of Microstructure Technology Karlsruhe Institute of TechnologyKarlsruhe 76344Germany Shanghai Artificial Intelligence Laboratory Shanghai 200444P.R.China Department of Applied Physics Chongqing UniversityChongqing 400044P.R.China

The influence of a mechanical structure's volume increment on the volume power density (VPD) of triboelectric nanogenerators (TENGs) is often neglected when considering surface charge density and surface power density. This paper aims to address this gap by introducing a standardized VPD metric for a more comprehensive evaluation of TENG performance. The study specifically focuses on 2 frequency-up mechanisms, namely, the integration of planetary gears (PG-TENG) and the implementation of a double-cantilever structure (DC-TENG), to investigate their impact on VPD. The study reveals that the PG-TENG achieves the highest volume average power density, measuring at 0.92 W/m^(3). This value surpasses the DC-TENG by 1.26 times and the counterpart TENG by a magnitude of 69.9 times. Additionally, the PG-TENG demonstrates superior average power output. These findings introduce a new approach for enhancing TENGs by incorporating frequency-up mechanisms, and highlight the importance of VPD as a key performance metric for evaluating TENGs.

关键词： increment neglected considering

On-Line Detection of Porosity in Gas Tungsten Arc Welding of Aluminum Alloy Based on Spectrum Features

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Journal of Shanghai Jiaotong university(Science) 2024年第2期29卷 339-348页

作者：蒋浩强陈善本许靖远 School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The real-time detection of porosity in welding process is an important problem to be solved in intelligent welding manufacturing.A new on-line detection method for porosity of aluminum alloy in robotic arc welding based on arc spectrum is proposed in this ***,k-shape and the improved k-means were used for the initial feature selection of the preprocessed arc spectrum to reduce the data ***,the secondary feature selection was carried out based on the importance of features to further reduce feature ***,the optimal sample label library was established by combining the final characteristic parameters and the X-ray pictures of ***,an on-line detection method of porosity in gas tungsten arc welding of aluminum alloy based on light gradient boosting machine(LightGBM)was *** with extreme gradient boosting(XGBoost)and categorical boosting(CatBoost),this method can achieve better detection *** new method proposed in this paper can be used to detect other welding defects,which is helpful to the development of intelligent welding technology.

关键词： porosity detection robotic arc welding arc spectrum

石油天然气行业科技成果评价体系构建与评价方法优化

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天然气工业 2024年第7期44卷 174-185页

作者：任利明罗强陈颖杰徐婧源李莉龙毅文雯四川省石油学会中国石油西南油气田公司四川大学

科技成果评价是科技奖励的核心工作之一,其评价结果对科技奖励的最终决策有着重要的作用。但长期以来国内的科技成果评价工作面临评价指标盲目套用、评价过程中个人价值与科学道德精神缺乏规范统一等方面的诸多问题。为此,以石油天然气... 详细信息

科技成果评价是科技奖励的核心工作之一,其评价结果对科技奖励的最终决策有着重要的作用。但长期以来国内的科技成果评价工作面临评价指标盲目套用、评价过程中个人价值与科学道德精神缺乏规范统一等方面的诸多问题。为此,以石油天然气行业科技成果评价工作为例,建立了一套考虑科学、技术、经济、社会价值的科技成果评价体系,并进行了权重赋值,最后通过项目实例来验证了方法的可靠性。研究结果表明:①构建的石油天然气行业科技成果评价指标体系包含4个一级指标、16个二级指标,并根据基础研究、应用研究、技术开发和产业化、软科学4类成果侧重不同,对一级指标分别赋值,以反映科技项目的研究性质和产出成果价值的差异;②在同行评议机制下,兼顾专家在科技成果所属研究方向的专业性以及专家与科技成果主体间的竞争性,基于直觉模糊理论建立了石油天然气科技成果评价模型,从专家对成果熟知度与专业匹配程度、专家评价一致性以及客观公正性3方面综合修正专家打分,有效消除专家评价中各种主观因素的干扰。结论认为,建立的石油天然气行业科技成果评价体系能够全面真实评价科技成果的创新水平和应用价值,兼顾科技成果普遍特点和石油天然气行业科技成果的独特性,其认识和成果可为其他行业科技成果评价提供参考和借鉴。

关键词：石油天然气行业科技成果评价科技奖励五元价值评价指标体系评价模型

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燃煤发电锅炉掺氨燃烧技术研究进展及应用分析

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能源科技 2024年第4期22卷 43-47页

作者：阮仁晖许景元崔保崇西安交通大学热流科学与工程教育部重点实验室陕西西安710049

燃煤机组掺氨燃烧是从燃烧源头减碳的有效方法。由于氨与煤在物理和化学特性上存在显著差异,导致氨煤混燃存在诸多技术难题。通过总结国内外氨煤混燃的基础研究、技术开发与中试研究,以及工业应用的研究进展,提出大型燃煤电站锅炉掺烧... 详细信息

燃煤机组掺氨燃烧是从燃烧源头减碳的有效方法。由于氨与煤在物理和化学特性上存在显著差异,导致氨煤混燃存在诸多技术难题。通过总结国内外氨煤混燃的基础研究、技术开发与中试研究,以及工业应用的研究进展,提出大型燃煤电站锅炉掺烧面临的挑战,包括氨煤混燃中NO_(x)排放控制、氨对锅炉受热面的腐蚀和氨供应系统与原有系统的耦合运行控制等。以600 MW机组为例,对比计算了掺氨前后的度电成本,发现液氨成本是制约燃煤机组大比例掺氨燃烧的主要原因之一。

关键词：燃煤锅炉掺氨燃烧技术 NOx控制技术

褐铁矿型和蛇纹石型红土镍矿提取镍钴的工艺研究

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中国资源综合利用 2024年第7期42卷 1-5页

作者：杨均流徐敬元肖桂龙巴斯夫(中国)有限公司上海200120 北方矿业有限责任公司北京100053 埃赫曼(上海)贸易有限公司上海200120

红土镍矿成分复杂,镍与钴的含量较低,主要类型有褐铁矿型和蛇纹石型。试验采用不同工艺对两种红土镍矿进行浸出,从而提取镍和钴。褐铁矿型红土镍矿采用拌酸熟化-水浸工艺进行处理。试验结果表明,当硫酸和红土镍矿的质量比为1.84时,镍与... 详细信息

红土镍矿成分复杂,镍与钴的含量较低,主要类型有褐铁矿型和蛇纹石型。试验采用不同工艺对两种红土镍矿进行浸出,从而提取镍和钴。褐铁矿型红土镍矿采用拌酸熟化-水浸工艺进行处理。试验结果表明,当硫酸和红土镍矿的质量比为1.84时,镍与钴的浸出率均超过97%,酸度越高,镍与钴的浸出率也越高;不管是先拌酸熟化再浸出,还是直接浆化加酸浸出,对镍与钴的浸出率影响不明显;在浸出过程中,添加还原剂,可使钴浸出率超过96%,还原剂的加入有利于钴的浸出,但对镍的浸出影响不大。蛇纹石型红土镍矿则采用常压预浸-加压浸出工艺进行处理。试验结果表明,当总酸矿比为0.53~0.58 t/t矿时,镍与钴的浸出率均超过74%,加压浸出液的铁含量约为5 g/L,残酸含量为15~21 g/L。

关键词：红土镍矿褐铁矿型蛇纹石型拌酸熟化水浸预浸加压浸出

科尔沁区域典型公路段建设沿线植被覆盖度演变规律研究

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哈尔滨师范大学自然科学学报 2024年第1期40卷 89-94页

作者：徐敬媛周嘉李昕航周芳冰寒区地理环境监测与空间信息服务黑龙江省重点实验室黑龙江省寒区生态安全协同创新中心

选取铁力-科尔沁右翼中旗高速公路吉林段(G1015)2003年(建设前)、2015年(建设中)、2021年(建设后)的Landsat8影像作为数据源,并基于缓冲区归一化植被指数(NDVI)、植被覆盖度(FVC)对G105线路段区域植被时空变化特征进行研究分析,结果表明... 详细信息

选取铁力-科尔沁右翼中旗高速公路吉林段(G1015)2003年(建设前)、2015年(建设中)、2021年(建设后)的Landsat8影像作为数据源,并基于缓冲区归一化植被指数(NDVI)、植被覆盖度(FVC)对G105线路段区域植被时空变化特征进行研究分析,结果表明:公路建设前,研究区范围内以中植被覆盖度为主,而公路建设期间以及公路建设完成以后,研究区范围内则转变为以低植被覆盖度为主.与公路建设前相比沿线周边环境低植被覆盖度所占面积比例增加了54.28%,中低植被覆盖度降低了10.64%,中植被覆盖度降低了16.48%.由此可见,高速公路建设对沿线周边环境植被产生影响严重.而建设完成后中等以上植被覆盖度增加了1.7%,植被覆盖状况有所好转,逐渐趋于新的生态平衡.继而通过铁科公路沿线植被覆盖时序演变规律,明晰公路建设对生态环境的影响因素,并在此基础上提出绿色可持续发展路径.

关键词：高速公路建设归一化植被指数演变规律

经颅多普勒对成人卵圆孔未闭的诊断及价值研究

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智慧健康 2024年第10期10卷 1-3页

作者：何丽寇明倩徐靖媛王文萱白银市第一人民医院电生理科甘肃白银730900

目的探究经颅多普勒对成人卵圆孔未闭的临床诊断。方法选取2022年6月—2023年6月在本院神经内科就诊的78例不明原因脑卒中或偏头痛患者为研究对象,按照检查方法分为试验1组(n=39)与试验2组(n=39),试验1组应用经颅多普勒超声检查,试验2... 详细信息

目的探究经颅多普勒对成人卵圆孔未闭的临床诊断。方法选取2022年6月—2023年6月在本院神经内科就诊的78例不明原因脑卒中或偏头痛患者为研究对象,按照检查方法分为试验1组(n=39)与试验2组(n=39),试验1组应用经颅多普勒超声检查,试验2组应用经胸心脏超声心动图检查。比较两组诊断的阳性率、上腔静脉血流频谱等情况。结果试验1组检查卵圆孔未闭的阳性率明显高于试验2组,组间差异有统计学意义(P0.05);但静息状态时,D波较S波峰值速度明显降低,差异有统计学意义(P<0.05);瓦氏呼吸下,D波也明显低于S波峰值速度,差异有统计学意义(P<0.05)。试验1组分流角度明显低于试验2组,差异有统计学意义(P<0.05);隧道长度、原发隔活动度明显高于试验2组,差异有统计学意义(P<0.05)。结论经颅多普勒超声检测成人卵圆孔未闭具有更高的诊断价值,能清晰观察到脑部解剖结构及血流动力变化,可为临床诊治提供有力的依据。

关键词：经颅多普勒成人卵圆孔未闭诊断价值

高效液相色谱-三重四极杆串联质谱法测定一次性静脉留置针中双酚A残留量

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中国药业 2024年第7期33卷 79-83页

作者：刘慧王健李奇王紫芸苟彦彦许静远徐力江苏省扬州市食品药品检验检测中心江苏扬州225000 常熟理工学院生物与食品工程学院江苏苏州215500

目的建立测定一次性静脉留置针中双酚A残留量的高效液相色谱-三重四极杆串联质谱法。方法以乙腈为溶剂,超声提取静脉留置针样品中残留的双酚A。色谱柱为Waters Acquity Premier BEH C_(18)柱(100 mm×2.1 mm,1.7μm),流动相为0.05%氨水... 详细信息

目的建立测定一次性静脉留置针中双酚A残留量的高效液相色谱-三重四极杆串联质谱法。方法以乙腈为溶剂,超声提取静脉留置针样品中残留的双酚A。色谱柱为Waters Acquity Premier BEH C_(18)柱(100 mm×2.1 mm,1.7μm),流动相为0.05%氨水-甲醇(28∶72,V/V),流速为0.3 mL/min,柱温为30℃,进样量为2μL;三重四极杆质谱,电喷雾电离离子源,负离子、多反应监测模式扫描,气帘气、喷雾气、辅助加热气气压分别为25,55,55 psi,离子化电压为4500 V,定量离子对质荷比(m/z)为227.1/133.0。结果双酚A的质量浓度在5.42~216.8 ng/mL范围内与峰面积线性关系良好(r=0.9999,n=6);检测限为0.1084 ng/mL,定量限为1.084 ng/mL;精密度、重复性试验结果的RSD均小于4.0%;加样回收率为90.44%,RSD为1.27%(n=6)。市售静脉留置针样品中双酚A的残留量最高为9213.34 ng/g。结论该方法操作简便、灵敏度高、重复性好、结果准确,可用于一次性静脉留置针中双酚A残留量的测定。

关键词：高效液相色谱-三重四极杆串联质谱法双酚A 一次性静脉留置针残留量

Target-triggered hairpin-free chain-branching growth of DNA dendrimers for contrast-enhanced imaging in living cells by avoiding signal dispersion

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Chinese Chemical Letters 2022年第2期33卷 773-777页

作者： Jiaqi Deng jingyuan xu Minzhi Ouyang Zhen Zou Yanli Lei Junbin Li Zhihe Qing Ronghua Yang Hunan Provincial Key Laboratory of Cytochemistry School of Chemistry and Food EngineeringChangsha University of Science and TechnologyChangsha 410114China Laboratory of Chemical Biology&Traditional Chinese Medicine Research Ministry of EducationCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China Department Ultrasound Diagnosis The Second Xiangya HospitalCentral South UniversityChangsha 410011China

The development of amplification strategies is one of the central challenges for detection of lowabundance targets. One-to-many(1:M) amplification strategies in which one target lights many signal probes, has improved the detection sensitivity in bulk solution, but with discounted contrast in cell imaging, because the lighted probes are dissociative and dispersible. In this work, a one-to-large(1:L) signaling mechanism, in which the lighted probes were orderly connected to each other, was conceptually proposed to enhance the contrast in cell imaging by avoiding signal dispersion in amplification. Accordingly,target-triggered hairpin-free chain-branching assembly(HFCBA) holds great potential to implement the1:L mechanism, but using it in cell imaging has yet to be demonstrated. As a proof of concept, a group of probes were first programmed to implement mi RNA-21-triggered HFCBA. After transfection of probes,gradually-growing signal flares in cells were monitored along with the growth of DNA dendrimers;and the in situ fluorescence accumulation in HFCBA resulted in highly-enhanced contrast to the surrounding by avoiding signal dispersion in amplification. The contrast-enhanced imaging with signal amplification is significant for biological analysis and molecular medicine. We expect the 1:L mechanism will provide a new thought for high-performance imaging of biomarkers in cells.

关键词： Cell imaging Amplification Signal dispersion Self-assembly DNA dendrimers

Hepatocyte growth factor protects pulmonary endothelial barrier against oxidative stress and mitochondria-dependent apoptosis

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Chinese Medical Journal 2022年第7期135卷 837-848页

作者： Shanshan Meng Feiping Xia jingyuan xu Xiwen Zhang Ming xue Mingyuan Gu Fengmei Guo Yingzi Huang Haibo Qiu Yi Yang Jiangsu Provincial Key Laboratory of Critical Care Medicine Department of Critical Care MedicineZhongda HospitalSchool of MedicineSoutheast UniversityNanjingJiangsu 210009China

Background:Pulmonary microvascular endothelial cells(PMVECs)were not complex,and the endothelial barrier was destroyed in the pathogenesis progress of acute lung injury(ALI)/acute respiratory distress syndrome(ARDS).Previous studies have demonstrated that hepatocyte growth factor(HGF),which was secreted by bone marrow mesenchymal stem cells,could decrease endothelial *** investigated whether mTOR/STAT3 signaling acted in HGF protective effects against oxidative stress and mitochondria-dependent apoptosis in lipopolysaccharide(LPS)-induced endothelial barrier dysfunction and ALI ***:In our current study,we introduced LPS-induced PMEVCs with HGF *** investigate the effects of mammalian target of rapamycin(mTOR)/signal transducer and activator of transcription 3(STAT3)pathway in endothelial oxidative stress and mitochondria-dependent apoptosis,mTOR inhibitor rapamycin and STAT3 inhibitor S3I-201 were,respectively,used to inhibit mTOR/STAT3 ***,lentivirus vector-mediatedmTORC1(Raptor)andmTORC2(Rictor)gene knockdown modifications were introduced to evaluatemTORC1 andmTORC1 *** measurement,reactive oxygen species(ROS)production,mitochondrial membrane potential and protein,cell proliferation,apoptosis,and endothelial junction protein were detected to evaluate HGF ***,we used the ALI mouse model to observe the mitochondria pathological changes with an electron microscopein ***:Our study demonstrated that HGF protected the endothelium via the suppression of ROS production and intracellular calcium uptake,which lead to increased mitochondrial membrane potential(JC-1 and mitochondria tracker green detection)and specific proteins(complex I),raised anti-apoptosis Messenger Ribonucleic Acid level(B-cell lymphoma 2 and Bcl-xL),and increased endothelial junction proteins(VE-cadherin and occludin).Reversely,mTOR inhibitor rapamycin and STAT3 inhibitor S3I-201 could raise oxidative stress and mitochondria-de

关键词： Hepatocyte growth factor Acute respiratory distress syndrome Endothelial barrier mTOR/STAT3 pathway Permeability