In this paper,by proposing a novel and low-cost Ag salt paste,a robustly and large-area(35×35 mm^(2))bare Cu to Cu bonding was realized under a low sintering pressure of 0.8 MPa and a low sintering temperature of...In this paper,by proposing a novel and low-cost Ag salt paste,a robustly and large-area(35×35 mm^(2))bare Cu to Cu bonding was realized under a low sintering pressure of 0.8 MPa and a low sintering temperature of 300℃ in air atmospheric conditions.The relationship between the bonding strength and microstructure changes of sintered Ag under various bonding conditions was investigated in detail.The large-area bonded plate exhibits low porosity about 10%and low percentage of voids,which result in ultra-high bonding strength over 58 MPa.More importantly,the introduction of reducing agent formic acid(CH_(2)O_(2))and the low porosity successfully improve the anti-oxidation of novel Ag salt paste during sintering process,result in pure Cu-Ag-Cu bonding.The cross-section of the Ag joints was obtained to explain the bonding pattern,in which Cu was oxidized only at the edge of the sintering interface,and no Cu oxide generated in middle bonding section.The development of novel Ag salt paste successfully addresses the energy-intensive process and low bonding strength faced by large-scale sintering,which greatly promotes the high-temperature applications of power device.展开更多
A superionic mixed metal iodide glass system [(PbI2 –CuI ) - Ag2O- V2O5- B2O3] has been prepared by splat quenching technique. The prepared glass samples are characterized by X-ray diffraction (XRD) and differential ...A superionic mixed metal iodide glass system [(PbI2 –CuI ) - Ag2O- V2O5- B2O3] has been prepared by splat quenching technique. The prepared glass samples are characterized by X-ray diffraction (XRD) and differential scanning calo- rimetry (DSC). The effect of mixed metal iodide salts concentration on electrical properties has been investigated by the complex impedance spectroscopy (CIS). AC conductivity analysis is carried out in the frequency range of 2MHz-1Hz at different temperatures and an enhancement in the conductivity with iodide salts is the main feature of the observed re- sults with an anomaly at 20 mole % of PbI2 –CuI.展开更多
We present here the first observation of cathodoluminescence (CL) images of Met.(Cu, Ag)-TCNQ anion radical salts organic thin films which were prepared in sat urated TCNQ/CH3CN liquid-phase by self-growth. The erperi...We present here the first observation of cathodoluminescence (CL) images of Met.(Cu, Ag)-TCNQ anion radical salts organic thin films which were prepared in sat urated TCNQ/CH3CN liquid-phase by self-growth. The erperiments were carried out by means of Hitachi S-450 type scanning electron microscopy(SEM). Comparsion of CL images with secondary electron(SE) images of the same point on the organic thin film indicates that the shape of Met.(Cu, Ag)-TCNQ in CL images corresponds very well to that in the SE images. The results observed also shows that the CL intensity of CuTCNQ is stronger than that of AgTCNQ under the same experimental conditions. Based on the above results, a brief discussion about the preliminary mechanism of CL from Met.(Cu,Ag)-TCNQ has been given.展开更多
Data on accumulation and concentration of chemical compounds recorded in an essentially unexplored area(Dome Argus)of the Indian Ocean sector of eastern Antarctica during the past 2,680 years(680 B.C. to 1999 A.D.) ar...Data on accumulation and concentration of chemical compounds recorded in an essentially unexplored area(Dome Argus)of the Indian Ocean sector of eastern Antarctica during the past 2,680 years(680 B.C. to 1999 A.D.) are presented. During the first 1, 700 years(680 B. C. to 1000 A. D.), the accumulation data shows a slightly decreasing trend, while chemical ions appear to be stable, representing a stable climatic condition. An intensive increasing trend of the accumulation occurred during the 12^(th) to 14^(th) century. The period from 15^(th) to 19^(th) century was characterized by a rapid reducing accumulation and concentrations of volatile compounds suffering post-depositional loss linked to sparse precipitation amount,which was temporally consistent with the Little Ice Age(LIA) episode. Comparison between observed accumulation rates with other eastern Antarctic ice cores show a consistent decreasing trend during LIA, while sea salt and dust-originated ions increased due to sea ice extent and intensified atmospheric transportation. Distribution of volcanic originated sulfate over the Antarctic continent show a significant change during the 15^(th) century, coincident with the onset of the LIA. These results are important for the assessment of Antarctic continent mass balance and associated interpretation of the Dome A deep ice core records.展开更多
In this paper, the interferences of X-ray image noise on a bone age model, Xception model, were studied. We conduct a comparative experiment test according to the output performance of the neural network model using b...In this paper, the interferences of X-ray image noise on a bone age model, Xception model, were studied. We conduct a comparative experiment test according to the output performance of the neural network model using both the original image training and noise-added (Gaussian noise plus salt-pepper noise) training, and analyze the anti-interference ability of the Xception model, hoping to improve it through noise enhancement training and generalize the application ability of the model. The results show that the model trained with noise-added (Gaussian noise plussalt-pepper noise) images can make predictions that are more robust and less affected by the image disturbances, such as image noise.展开更多
背景:衰老是一个不可逆的过程,其特征与基因、饮食和环境有关。哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTor)作为生长发育的中心调节剂对衰老、运动及不良饮食导致的负面影响具有调节作用,这些作用与mTor及其复合物的...背景:衰老是一个不可逆的过程,其特征与基因、饮食和环境有关。哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTor)作为生长发育的中心调节剂对衰老、运动及不良饮食导致的负面影响具有调节作用,这些作用与mTor及其复合物的活性相互关联。然而各因素间的相互联系仍不十分清楚,如mTor、运动对衰老的影响。目的:拟通过研究运动、高脂/高盐饮食和mTor在衰老中的关系,从而对衰老的防治机制有更加全面的认识。方法:①文献资料法,通过在CNKI及Web of Science核心合集数据库中进行检索,围绕“mTor基因(mammalian target of rapamycin/mTor)、运动(exercise)、高脂肪/高盐饮食(high-fat diet/high-salt diet)及衰老(aging)”等关键词进行关键词的组合搜索,对相关文献进行检索、查阅和筛选,为文章提供理论支撑。②对比分析法,通过对所得到的有效文献进行仔细阅读,比较各文献间的差异,为文章论点提供理论基础。③通过对比分析文献间的异同点,明确各指标的定义及关系,从而理清文章思路。结果与结论:mTor与衰老密切相关,通过分析文献,认为mTor的2个复合物mTorC1和mTorC2在衰老、运动和骨骼肌的生长发育中起着重要作用。此外,mTor介导的S6K1、Akt、FOXO和4E-BP1信号通路与运动、高脂饮食、高盐饮食和骨骼肌/心脏衰老密切相关。展开更多
基金partly supported a project (JPNP14004) commissioned by the New Energy and Industrial Technology Development Organization (NEDO)the supporting from TOPPAN FORMS CO.,LTD,Japan
文摘In this paper,by proposing a novel and low-cost Ag salt paste,a robustly and large-area(35×35 mm^(2))bare Cu to Cu bonding was realized under a low sintering pressure of 0.8 MPa and a low sintering temperature of 300℃ in air atmospheric conditions.The relationship between the bonding strength and microstructure changes of sintered Ag under various bonding conditions was investigated in detail.The large-area bonded plate exhibits low porosity about 10%and low percentage of voids,which result in ultra-high bonding strength over 58 MPa.More importantly,the introduction of reducing agent formic acid(CH_(2)O_(2))and the low porosity successfully improve the anti-oxidation of novel Ag salt paste during sintering process,result in pure Cu-Ag-Cu bonding.The cross-section of the Ag joints was obtained to explain the bonding pattern,in which Cu was oxidized only at the edge of the sintering interface,and no Cu oxide generated in middle bonding section.The development of novel Ag salt paste successfully addresses the energy-intensive process and low bonding strength faced by large-scale sintering,which greatly promotes the high-temperature applications of power device.
文摘A superionic mixed metal iodide glass system [(PbI2 –CuI ) - Ag2O- V2O5- B2O3] has been prepared by splat quenching technique. The prepared glass samples are characterized by X-ray diffraction (XRD) and differential scanning calo- rimetry (DSC). The effect of mixed metal iodide salts concentration on electrical properties has been investigated by the complex impedance spectroscopy (CIS). AC conductivity analysis is carried out in the frequency range of 2MHz-1Hz at different temperatures and an enhancement in the conductivity with iodide salts is the main feature of the observed re- sults with an anomaly at 20 mole % of PbI2 –CuI.
文摘We present here the first observation of cathodoluminescence (CL) images of Met.(Cu, Ag)-TCNQ anion radical salts organic thin films which were prepared in sat urated TCNQ/CH3CN liquid-phase by self-growth. The erperiments were carried out by means of Hitachi S-450 type scanning electron microscopy(SEM). Comparsion of CL images with secondary electron(SE) images of the same point on the organic thin film indicates that the shape of Met.(Cu, Ag)-TCNQ in CL images corresponds very well to that in the SE images. The results observed also shows that the CL intensity of CuTCNQ is stronger than that of AgTCNQ under the same experimental conditions. Based on the above results, a brief discussion about the preliminary mechanism of CL from Met.(Cu,Ag)-TCNQ has been given.
基金financially supported by the National Natural Science Foundation of China (41671063, 41425003, 41476164, 41671073, and 41721091)Supporting funds also include that from the State Oceanic Administration, the Youth Innovation Promotion Association, NIEER, and the State Key Laboratory of the Cryospheric Science
文摘Data on accumulation and concentration of chemical compounds recorded in an essentially unexplored area(Dome Argus)of the Indian Ocean sector of eastern Antarctica during the past 2,680 years(680 B.C. to 1999 A.D.) are presented. During the first 1, 700 years(680 B. C. to 1000 A. D.), the accumulation data shows a slightly decreasing trend, while chemical ions appear to be stable, representing a stable climatic condition. An intensive increasing trend of the accumulation occurred during the 12^(th) to 14^(th) century. The period from 15^(th) to 19^(th) century was characterized by a rapid reducing accumulation and concentrations of volatile compounds suffering post-depositional loss linked to sparse precipitation amount,which was temporally consistent with the Little Ice Age(LIA) episode. Comparison between observed accumulation rates with other eastern Antarctic ice cores show a consistent decreasing trend during LIA, while sea salt and dust-originated ions increased due to sea ice extent and intensified atmospheric transportation. Distribution of volcanic originated sulfate over the Antarctic continent show a significant change during the 15^(th) century, coincident with the onset of the LIA. These results are important for the assessment of Antarctic continent mass balance and associated interpretation of the Dome A deep ice core records.
文摘In this paper, the interferences of X-ray image noise on a bone age model, Xception model, were studied. We conduct a comparative experiment test according to the output performance of the neural network model using both the original image training and noise-added (Gaussian noise plus salt-pepper noise) training, and analyze the anti-interference ability of the Xception model, hoping to improve it through noise enhancement training and generalize the application ability of the model. The results show that the model trained with noise-added (Gaussian noise plussalt-pepper noise) images can make predictions that are more robust and less affected by the image disturbances, such as image noise.
文摘背景:衰老是一个不可逆的过程,其特征与基因、饮食和环境有关。哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTor)作为生长发育的中心调节剂对衰老、运动及不良饮食导致的负面影响具有调节作用,这些作用与mTor及其复合物的活性相互关联。然而各因素间的相互联系仍不十分清楚,如mTor、运动对衰老的影响。目的:拟通过研究运动、高脂/高盐饮食和mTor在衰老中的关系,从而对衰老的防治机制有更加全面的认识。方法:①文献资料法,通过在CNKI及Web of Science核心合集数据库中进行检索,围绕“mTor基因(mammalian target of rapamycin/mTor)、运动(exercise)、高脂肪/高盐饮食(high-fat diet/high-salt diet)及衰老(aging)”等关键词进行关键词的组合搜索,对相关文献进行检索、查阅和筛选,为文章提供理论支撑。②对比分析法,通过对所得到的有效文献进行仔细阅读,比较各文献间的差异,为文章论点提供理论基础。③通过对比分析文献间的异同点,明确各指标的定义及关系,从而理清文章思路。结果与结论:mTor与衰老密切相关,通过分析文献,认为mTor的2个复合物mTorC1和mTorC2在衰老、运动和骨骼肌的生长发育中起着重要作用。此外,mTor介导的S6K1、Akt、FOXO和4E-BP1信号通路与运动、高脂饮食、高盐饮食和骨骼肌/心脏衰老密切相关。
