A preparation technology of semi-solid metal slurry introducing grain process （IGP） was developed. The effects of processing parameters on the microstructures of the semi-solid A356 Al-alloy slurries were investigat...A preparation technology of semi-solid metal slurry introducing grain process （IGP） was developed. The effects of processing parameters on the microstructures of the semi-solid A356 Al-alloy slurries were investigated, and the formation mechanism and morphology controlling of the spherical primary a（A1） grains were discussed. The results show that when the preparing slurry is 4 kg, IG size is 10 mm, dosage is 3.5% and dumping temperature （DT） is 611-617 ℃, the mean diameter of the primary a（A1） grains in the semi-solid slurries can reach 40-75 μm and the shape factor can reach 0.82-0.89. When the IG size is 10 mm, DT is 613℃and dosage is 2%-4%, the mean diameter can reach 45-82 μm and the shape factors can reach 0.78-0.88. With decreasing DT or increasing dosage properly, the primary α（A1） grain morphology is better. When QR=QA and Rh=Rc, as long as the DT is suitable, excellent semi-solid slurry can be produced. As a result of the IG melting, a large amount of dendritic fragments can become the direct source of the primary a（A1） grains. Meanwhile, many undercooled areas are formed, where abundant primary α（A1） grains are multiplied by heterogeneous nucleation.展开更多
The world situation is experiencing profound and complex changes. With the further deepening of economic globalization, various countries with interwoven interests are becoming increasingly interdependent and interrel...The world situation is experiencing profound and complex changes. With the further deepening of economic globalization, various countries with interwoven interests are becoming increasingly interdependent and interrelated. A large number of big developing countries are rising, adding fresh rich elements to the trend of development toward multi-polarity.展开更多
We propose an efficient method for the generation of an isolated attosecond pulse from the asymmetric molecular ions HeH^2＋ by adding a half-cycle-like field （HCLF） to the fundamental driving laser field. The high-...We propose an efficient method for the generation of an isolated attosecond pulse from the asymmetric molecular ions HeH^2＋ by adding a half-cycle-like field （HCLF） to the fundamental driving laser field. The high-order harmonic generation （HHG） is investigated by numerically sowing the time-dependent Schrodinger equation. By performing the time-frequency distributions and the electronic wave packet probability densities, we find that the optimizing combined field is not only useful for extending the HHG cutoff, but also for simplifying the recombination channels through controlling the electron localization. In addition, by adjusting the intensity of the HCLF, a dominant short quantum path is selected to contribute the HHG spectrum. As a result, a 75-as isolated attosecond pulse is obtained by superposing a proper range of the harmonics.展开更多
Tricyclic compound 6 was synthesized form compound 1 through sis steps, thus preblem of the stereochemistry of C2α-H being solved. The stereochemistry for introducing hydroxy groups at C3β and C4α positions in com...Tricyclic compound 6 was synthesized form compound 1 through sis steps, thus preblem of the stereochemistry of C2α-H being solved. The stereochemistry for introducing hydroxy groups at C3β and C4α positions in compound 1 was also described.展开更多
At the beginning of this New Year of 2013, we are very pleased to present the English edition of the Journal of Integrative Medicine （JIM）, a PubMed-indexed, peer-reviewed, open-access journal on integrative medicin...At the beginning of this New Year of 2013, we are very pleased to present the English edition of the Journal of Integrative Medicine （JIM）, a PubMed-indexed, peer-reviewed, open-access journal on integrative medicine. The JIM is a continuation of the former Chinese-language journal, the Journal of Chinese Integrative Medicine （JCIM）, established in 2003 and published in Shanghai. Integrative medicine, grounded in patient-centered, evidence-based practice, incorporates the broad spectrum of complementary and alternative medicine （CAM） and includes acupuncture and traditional Chinese medicine, Ayurveda medicine, herbal medicine, homeopathy, nutrition, chiropractic, mind-body medicine, taichi, qigong, and meditation, among other professions. In the past two decades, CAM has become one of the fastest growing branches of health care. CAM now commands attention worldwide and is rapidly being integrated into conventional medicine. China is the country in the world that has great number of scientists doing clinical and research work on integrative medicine. With this new, English-language publication, we are committed to make JIM an international platform for high-quality CAM papers and an open forum in which the different professions and international scholarly communities can exchange views, share research and their clinical experience, discuss CAM education, and confer about issues and problems in our various disciplines and in CAM as a whole in order to promote integrative medicine.展开更多
JOURNAL OF CHINA ORDNANCE, an official journal sponsored by China Ordnance Society and published half-yearly, aims to presenting the latest developments and achievements of the academic circles specializing in the fie...JOURNAL OF CHINA ORDNANCE, an official journal sponsored by China Ordnance Society and published half-yearly, aims to presenting the latest developments and achievements of the academic circles specializing in the field of ordnance science and technology. It provides a展开更多
Sustained and profound aridization process in north west China in Tertiary and Quaternary period and time of mankind history are discussed. The rain creased function of 3 set high mountain condensation systems in nort...Sustained and profound aridization process in north west China in Tertiary and Quaternary period and time of mankind history are discussed. The rain creased function of 3 set high mountain condensation systems in north west China is recognized once more. A sandstorm happened on 20th March 2002 in Alasan and Ejinaqi areas was very strong and arrived in Japan and Korea. For saving Alasan area from sandstorm a way of introducing sea water from Bohai to Alasan has been proposed. Four problems are replied in this paper. It is concluded that introducing sea water from Bohai to west China is the best way for sustainable development of west China.展开更多
Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measur...Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measure, a principal method is designed for quantifying the detectabilities of fault detection algorithms over special datasets.展开更多
I recently got the opportunity to visit China to attend a seminar organized by the China Counsel for the Promotion of International Trade(CCPIT),for participants from the Belt and Road Initiative(BRI)countries.The pur...I recently got the opportunity to visit China to attend a seminar organized by the China Counsel for the Promotion of International Trade(CCPIT),for participants from the Belt and Road Initiative(BRI)countries.The purpose of the seminar was to invite the delegates from BRI countries,and give them firsthand experience of the Chinese development miracle by introducing them to Chinese history,its governance methodology and how it has managed to carry out its significant progress in the last three decades,for example,by following policies that facilitated entrepreneurship,and providing businesses the right kind of platform.展开更多
As an enthusiast of travelling,a young French entrepreneur has dedicated her life to sharing the vitality of China’s eastern economic hub with more people.ON the streets of Shanghai,China’s eastern mega city,you can...As an enthusiast of travelling,a young French entrepreneur has dedicated her life to sharing the vitality of China’s eastern economic hub with more people.ON the streets of Shanghai,China’s eastern mega city,you can often see a young French woman leading a group of tourists around the city on citywalks,introducing the history and culture of the metropolis to them in Chinese,English,and French.展开更多
During the annual meeting of the National People’s Congress(NPC),China’s top legislature,in March,President Xi Jinping stressed focusing on high-quality development as the top priority and developing new quality pro...During the annual meeting of the National People’s Congress(NPC),China’s top legislature,in March,President Xi Jinping stressed focusing on high-quality development as the top priority and developing new quality productive forces according to local conditions while deliberating with lawmakers from Jiangsu Province.Following the path that President Xi emphasized,SAIC-GM-Wuling Automobile Co.,Ltd.has been committed to modernizing research and development(R&D),introducing intelligent manufacturing,upgrading the automobile industry.展开更多
Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patte...Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patterns in species-specific responses to extreme droughts.Here,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast China.We assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation index.The results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar plantations.The RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy effect.In contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial growth.Furthermore,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth rate.This study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and response.Our study improves our understanding of forest responses to extreme drought and highlights species differences in climate responses,offering crucial insights for optimizing species selection in sustainable afforestation and forest management in water-limited regions under the influence of climate change.展开更多
文摘A preparation technology of semi-solid metal slurry introducing grain process （IGP） was developed. The effects of processing parameters on the microstructures of the semi-solid A356 Al-alloy slurries were investigated, and the formation mechanism and morphology controlling of the spherical primary a（A1） grains were discussed. The results show that when the preparing slurry is 4 kg, IG size is 10 mm, dosage is 3.5% and dumping temperature （DT） is 611-617 ℃, the mean diameter of the primary a（A1） grains in the semi-solid slurries can reach 40-75 μm and the shape factor can reach 0.82-0.89. When the IG size is 10 mm, DT is 613℃and dosage is 2%-4%, the mean diameter can reach 45-82 μm and the shape factors can reach 0.78-0.88. With decreasing DT or increasing dosage properly, the primary α（A1） grain morphology is better. When QR=QA and Rh=Rc, as long as the DT is suitable, excellent semi-solid slurry can be produced. As a result of the IG melting, a large amount of dendritic fragments can become the direct source of the primary a（A1） grains. Meanwhile, many undercooled areas are formed, where abundant primary α（A1） grains are multiplied by heterogeneous nucleation.
文摘The world situation is experiencing profound and complex changes. With the further deepening of economic globalization, various countries with interwoven interests are becoming increasingly interdependent and interrelated. A large number of big developing countries are rising, adding fresh rich elements to the trend of development toward multi-polarity.
基金Supported by the National Natural Science Foundation of China under Grant No 11404204the Key Project of the Ministry of Education of China under Grant No 211025+1 种基金the Research Fund for the Doctoral Program of Higher Education of China under Grant No 20111404120004the Natural Science Foundation for Young Scientists of Shanxi Province under Grant No 2009021005
文摘We propose an efficient method for the generation of an isolated attosecond pulse from the asymmetric molecular ions HeH^2＋ by adding a half-cycle-like field （HCLF） to the fundamental driving laser field. The high-order harmonic generation （HHG） is investigated by numerically sowing the time-dependent Schrodinger equation. By performing the time-frequency distributions and the electronic wave packet probability densities, we find that the optimizing combined field is not only useful for extending the HHG cutoff, but also for simplifying the recombination channels through controlling the electron localization. In addition, by adjusting the intensity of the HCLF, a dominant short quantum path is selected to contribute the HHG spectrum. As a result, a 75-as isolated attosecond pulse is obtained by superposing a proper range of the harmonics.
文摘Tricyclic compound 6 was synthesized form compound 1 through sis steps, thus preblem of the stereochemistry of C2α-H being solved. The stereochemistry for introducing hydroxy groups at C3β and C4α positions in compound 1 was also described.
文摘At the beginning of this New Year of 2013, we are very pleased to present the English edition of the Journal of Integrative Medicine （JIM）, a PubMed-indexed, peer-reviewed, open-access journal on integrative medicine. The JIM is a continuation of the former Chinese-language journal, the Journal of Chinese Integrative Medicine （JCIM）, established in 2003 and published in Shanghai. Integrative medicine, grounded in patient-centered, evidence-based practice, incorporates the broad spectrum of complementary and alternative medicine （CAM） and includes acupuncture and traditional Chinese medicine, Ayurveda medicine, herbal medicine, homeopathy, nutrition, chiropractic, mind-body medicine, taichi, qigong, and meditation, among other professions. In the past two decades, CAM has become one of the fastest growing branches of health care. CAM now commands attention worldwide and is rapidly being integrated into conventional medicine. China is the country in the world that has great number of scientists doing clinical and research work on integrative medicine. With this new, English-language publication, we are committed to make JIM an international platform for high-quality CAM papers and an open forum in which the different professions and international scholarly communities can exchange views, share research and their clinical experience, discuss CAM education, and confer about issues and problems in our various disciplines and in CAM as a whole in order to promote integrative medicine.
文摘JOURNAL OF CHINA ORDNANCE, an official journal sponsored by China Ordnance Society and published half-yearly, aims to presenting the latest developments and achievements of the academic circles specializing in the field of ordnance science and technology. It provides a
文摘Sustained and profound aridization process in north west China in Tertiary and Quaternary period and time of mankind history are discussed. The rain creased function of 3 set high mountain condensation systems in north west China is recognized once more. A sandstorm happened on 20th March 2002 in Alasan and Ejinaqi areas was very strong and arrived in Japan and Korea. For saving Alasan area from sandstorm a way of introducing sea water from Bohai to Alasan has been proposed. Four problems are replied in this paper. It is concluded that introducing sea water from Bohai to west China is the best way for sustainable development of west China.
基金supported by the National Key R&D Program of China (2021YFB1715000)the National Natural Science Foundation of China (U1811461, 62022013, 12150007, 62103450, 61832003, 62272137)。
文摘Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measure, a principal method is designed for quantifying the detectabilities of fault detection algorithms over special datasets.
文摘I recently got the opportunity to visit China to attend a seminar organized by the China Counsel for the Promotion of International Trade(CCPIT),for participants from the Belt and Road Initiative(BRI)countries.The purpose of the seminar was to invite the delegates from BRI countries,and give them firsthand experience of the Chinese development miracle by introducing them to Chinese history,its governance methodology and how it has managed to carry out its significant progress in the last three decades,for example,by following policies that facilitated entrepreneurship,and providing businesses the right kind of platform.
文摘As an enthusiast of travelling,a young French entrepreneur has dedicated her life to sharing the vitality of China’s eastern economic hub with more people.ON the streets of Shanghai,China’s eastern mega city,you can often see a young French woman leading a group of tourists around the city on citywalks,introducing the history and culture of the metropolis to them in Chinese,English,and French.
文摘During the annual meeting of the National People’s Congress(NPC),China’s top legislature,in March,President Xi Jinping stressed focusing on high-quality development as the top priority and developing new quality productive forces according to local conditions while deliberating with lawmakers from Jiangsu Province.Following the path that President Xi emphasized,SAIC-GM-Wuling Automobile Co.,Ltd.has been committed to modernizing research and development(R&D),introducing intelligent manufacturing,upgrading the automobile industry.
基金supported by the National Natural Science Foundation of China(Nos.32220103010,32192431,31722013)the National Key R&D Program of China(Nos.2023YFF1304201,2020YFA0608100)+1 种基金the Major Program of Institute of Applied EcologyChinese Academy of Sciences(No.IAEMP202201)。
文摘Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patterns in species-specific responses to extreme droughts.Here,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast China.We assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation index.The results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar plantations.The RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy effect.In contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial growth.Furthermore,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth rate.This study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and response.Our study improves our understanding of forest responses to extreme drought and highlights species differences in climate responses,offering crucial insights for optimizing species selection in sustainable afforestation and forest management in water-limited regions under the influence of climate change.
