Using ab initio density functional theory calculations, we explore the three most stable structural phases, namely, α,β, and cubic(c) phases, of two-dimensional(2D) antimonene, as well as its isoelectronic counterpa...Using ab initio density functional theory calculations, we explore the three most stable structural phases, namely, α,β, and cubic(c) phases, of two-dimensional(2D) antimonene, as well as its isoelectronic counterparts SnTe and InI. We find that the band gap increases monotonically from Sb to SnTe to InI along with an increase in ionicity, independent of the structural phases. The band gaps of this material family cover the entire visible-light energy spectrum, ranging from 0.26 eV to 3.37 eV, rendering them promising candidates for optoelectronic applications. Meanwhile, band-edge positions of these materials are explored and all three types of band alignments can be achieved through properly combining antimonene with its isoelectronic counterparts to form heterostructures. The richness in electronic properties for this isoelectronic material family sheds light on possibilities to tailor the fundamental band gap of antimonene via lateral alloying or forming vertical heterostructures.展开更多
In recent years, with museums popularized by various cultural creative products, libraries are unwilling to lag behind. Recently, the National Library Cultural and Creative Artwork Store was officially opened. Meanwhi...In recent years, with museums popularized by various cultural creative products, libraries are unwilling to lag behind. Recently, the National Library Cultural and Creative Artwork Store was officially opened. Meanwhile, the Flagship Store of the National Library Cultural and Creative Union was launched on Tmall. Led by the National Library of China, 116 libraries across the country have "joined hands" to set up online shops, so as to jointly develop cultural creative products.展开更多
On July 20th, a signing ceremony between Setcore Group, Egypt represented by Mr. Tamer Nassar-Chairman of Group and the World Trade & Commerce Center, Dongyang-China represented by Mr. Jiang Yuejin-Mayor of Dongya...On July 20th, a signing ceremony between Setcore Group, Egypt represented by Mr. Tamer Nassar-Chairman of Group and the World Trade & Commerce Center, Dongyang-China represented by Mr. Jiang Yuejin-Mayor of Dongyang City was held at the Marriott Hotel in Zamalek-Cairo. This was win-win cooperation and exerted great significances on both sides. In this event, they exchange ideas on the economic issues of common concerned and signed a memorandum of understanding as well.展开更多
Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is a constellation with four instruments(launch date):GECAM-A/B(10 December 2020),GECAM-C(27 July 2022)and GECAM-D(13 March 2024),which ...Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is a constellation with four instruments(launch date):GECAM-A/B(10 December 2020),GECAM-C(27 July 2022)and GECAM-D(13 March 2024),which are dedicated to monitoring gamma-ray transients in all-sky.The primary science objectives of GECAM include Gamma-Ray Bursts(GRBs),Soft Gamma-ray Repeaters(SGRs),high energy counterparts of Gravitation Wave(GW)and Fast Radio Burst(FRB),Solar Flares(SFLs),as well as Terrestrial Gamma-ray Flashes(TGFs)and Terrestrial Electron Beams(TEBs).A series of observations and research have been made since the launch of GECAM-A/B.GECAM observations provide new insights into these highenergy transients,demonstrating the unique role of GECAM in the“multi-wavelength,multi-messenger”era.展开更多
In British Council-managed ELT projects in Chinese universities,Chinese project counterparts areselected from among the English-language teaching staff of the University.They work alongside aBritish Council-recruited ...In British Council-managed ELT projects in Chinese universities,Chinese project counterparts areselected from among the English-language teaching staff of the University.They work alongside aBritish Council-recruited lecturer(BCL)in developing whatever it is the project has been set up tocreate:a syllabus,teaching materials,a course,etc.During the lifetime of the project eachcounterpart is sent for a year’s postgraduate training(typically an MA in applied Linguistics)at aBritish university,the rationale being that the combination of training on the job and in the UK willequip them to take over the running of the project and ensure its long-term sustainability.This paperlooks at the staff development of the counterparts prior to their UK training.展开更多
In order to investigate the structure-odor relationship of odoriferous compounds and search for new aroma chemicals, seven acetals of 4-trimethylsilyl-3-cyclohexenone and their carbon counterparts were synthesized by ...In order to investigate the structure-odor relationship of odoriferous compounds and search for new aroma chemicals, seven acetals of 4-trimethylsilyl-3-cyclohexenone and their carbon counterparts were synthesized by Birch reduction of 4-substituted anisoles and then acetalization. Seven acetals of 4-trimethylsilylcyclohexanone and their carbon counterparts were synthesized similarly. Structures of all new compounds were determined by MS, IR and ~1H NMR, and their characteristic odors were evaluated as well. The characteristic odors of the acetals formed by 4-substituted-3-cyclohexenone and 1, 2-diols are fruity and woody. The acetals formed from 1, 3-diols are woody, and formed with 1, 4-diols are very faint in odor. Odors of acetals of 4-substituted cyclohexanone are all very weak. As a whole, odors of organosilicon compounds are weaker, but somewhat more delicate than their carbon counter- parts.展开更多
LIGO/Virgo S190814 bv is the first high-probability neutron star–black hole(NSBH)merger candidate,whose gravitational waves(GWs)triggered LIGO/Virgo detectors at21:10:39.012957 UT,14 August 2019.It has a probability&...LIGO/Virgo S190814 bv is the first high-probability neutron star–black hole(NSBH)merger candidate,whose gravitational waves(GWs)triggered LIGO/Virgo detectors at21:10:39.012957 UT,14 August 2019.It has a probability>99%of being an NSBH merger,with a low false alarm rate(FAR)of one per 1.559 e+25 years.For an NSBH merger,electromagnetic counterparts(especially short gamma-ray bursts(GRBs))are generally expected.However,no electromagnetic counterpart has been found in the extensive follow-up observing campaign.In the present work,we propose a novel explanation for this null result.In our scenario,LIGO/Virgo S190814 bv is just a GW mirror image of the real NSBH merger which should have been detected before 14 September 2015,but at that time we had no ability to detect its GW signals.The electromagnetic counterparts associated with the real NSBH merger should be found in the archive data before 14 September 2015.In this work,we indeed find nine short GRBs that are possibly electromagnetic counterparts.展开更多
Bacillus megaterium BM302 bred by ion-beam implantation produces L-sorbose dehydrogenase accelerative protein (SAP) to accelerate the activity of L-sorbose dehydrogenase (SDH) of Gluconobacter oxydans in the 2-ket...Bacillus megaterium BM302 bred by ion-beam implantation produces L-sorbose dehydrogenase accelerative protein (SAP) to accelerate the activity of L-sorbose dehydrogenase (SDH) of Gluconobacter oxydans in the 2-keto-L-gulonic acid (2KLG) fermentation from L-sorbose by the mixed culture of B. megaterium BM302 and G. oxydans. The SAP purified by three chromatographic steps gave 35-fold purification with a yield of 13% and a specific activity of 5.21 units/mg protein. The molecular weight of the purified SAP was about 58 kDa. The SDH accelerative activity of SAP at pH 7 and 50℃ was the highest. Additionally, it retained 60% activity at a pH range of 6.5 ~ 10 and was stable at 20℃ ~ 60℃. After 0.32-unit SAP was added to the single cultured G. oxydans strains, the SDH activity was apparently accelerated and the 2KLG yield of GO29, GO112, GO and GI13 was enhanced 2.1, 3.3, 3.5 and 2.9 folds respectively over that of the strains without the addition of SAP.展开更多
Cross-linked enzyme aggregates(CLEAs) of nitrile hydratase(NHase) ES-NHT-118 from Escherichia coli were prepared by using ammonium sulfate as precipitating agent followed by cross-linking with dextran polyaldehyde for...Cross-linked enzyme aggregates(CLEAs) of nitrile hydratase(NHase) ES-NHT-118 from Escherichia coli were prepared by using ammonium sulfate as precipitating agent followed by cross-linking with dextran polyaldehyde for the first time. In this process, egg white was added as protein feeder for facilitating the formation of CLEAs. The optimal conditions of the immobilization process were determined. Michaelis constants(Km) of free NHase and NHase CLEAs were also determined. The NHase CLEAs exhibited increased stability at varied pH and temperature conditions compared to its free counterpart. When exposed to high concentrations of acrylamide, NHase CLEAs also exhibited effective catalytic activity.展开更多
Interprovincial counterpart support is a cooperative system used by local governments to achieve horizontal flow of resources based on cross-regional cooperation.Existing research has mainly focused on governance ef‐...Interprovincial counterpart support is a cooperative system used by local governments to achieve horizontal flow of resources based on cross-regional cooperation.Existing research has mainly focused on governance ef‐ficiency,institutional advantages,and ranking incentives while ignoring the scrambling behavior and opera‐tional mechanisms of local governments formed by ranking incentives and territorial responsibilities.This study selected the Wenchuan earthquake,Yushu earthquake,and COVID-19 as three typical cases.We con‐structed a theoretical framework for competition among provincial local governments and found that competi‐tion in interprovincial disaster counterpart support followed a dual behavioral logic of“striving to be first”and“fear of being last”.Specifically,local governments will choose striving to be first under the logic of time coercion,content games,and territorial responsibility;they will choose fear of being last under the logic of re‐sponsibility avoidance and moral pressure.This type of scrambling-based horizontal competition reflects the logic of local government competition tournaments.This study further revealed the specific processes,mecha‐nisms,and results of horizontal local government competition,which can provide inspiration for cross regional and provincial cooperation.展开更多
The wear mechanism of metallic card clothing,used in textile industry,was analyzed.A fast wear test for metallic card clothing racks was developed,which was used as collecting the wear metal particles.The failure type...The wear mechanism of metallic card clothing,used in textile industry,was analyzed.A fast wear test for metallic card clothing racks was developed,which was used as collecting the wear metal particles.The failure type of card clothing was analyzed by the mean of scanning electron microscopy(SEM)and ferro-spectrum technology.The results show that the main wear mechanism of metallic card clothing is low load and high repetition interval fatigue wear caused by friction force between fiber and metal wire teeth.The appropriate quenching microstructure,which improves the wear resistance of the metallic card clothing rack is also discussed.展开更多
Eighty three cases of low vision patients (144 eyes) were examined with distant visual aids. The average visual acuity of the 144 eyes before refraction was approximately 0.07, while the counterpart afterwards was abo...Eighty three cases of low vision patients (144 eyes) were examined with distant visual aids. The average visual acuity of the 144 eyes before refraction was approximately 0.07, while the counterpart afterwards was about 0.1 (p【0.01), With the 4x monocular focusable aid, acuity improved in 142 eyes out of the 144 eyes. The combined use of clip-on distance aid and the spectacle reading aid was observed to be especially suitable for partially sighted students.The mean MEF of 142 eyes was 0.9435±0.2068. The paired T-test between the difference of actual magnification and theoretical magnification was not significant at the 5% level. The factors contributing to the variance of MEF were discussed.展开更多
In the blood fluke Schistosoma mansoni a functionally active, monomeric, phospholipid hydroperoxide glutathione peroxidase (PHGPx) has been purified and characterized. This enzyme contains a catalytically active selen...In the blood fluke Schistosoma mansoni a functionally active, monomeric, phospholipid hydroperoxide glutathione peroxidase (PHGPx) has been purified and characterized. This enzyme contains a catalytically active selenocysteine. The protein has been shown to be the product of a cloned gene, previously referred to as a glutathione peroxidase gene. S. mansoni PHGPx has been found 5 times more abundant in female than in male worm extract. As in vertebrate PHGPx, homology alignment indicates that the residues involved in the glutathione binding by the tetrameric cellular glutathione peroxidase are mutated in the S. mansoni enzyme. Thus, this aspect appears a landmark of the PHGPx-type of glutathione peroxidases,which might be of functional relevance展开更多
The use of credit default swaps (CDSs) has become increasingly popular over time. Between 2002 and 2007, gross notional amounts outstanding grew from below S2 trillion to nearly S60 trillion. The recent crisis has r...The use of credit default swaps (CDSs) has become increasingly popular over time. Between 2002 and 2007, gross notional amounts outstanding grew from below S2 trillion to nearly S60 trillion. The recent crisis has revealed several shortcomings in CDS market practices and structure. In addition, management of counterparty risk has proved insufficient, as has in some instances the settlement of contracts following a credit event. However, past problems should not distract from the potential benefits of these instruments. In particular, CDSs help complete markets, as they provide an effective means to hedge and trade credit risk. CDSs allow financial institutions to better manage their exposures, and investors benefit from an enhanced investment universe. The purpose of this paper is to present a complete and practical exposition of the CDS market and to explore how the development of the CDS market has played an important role in the credit risk markets. Currently, the CDS market is transforming into a more stable system. Various measures are being put in place to help enhance market transparency and mitigate operational and systemic risk. In particular, central counterparties have started to operate, which will eventually lead to an improved management of individual as well as system-wide risks.展开更多
The“counterpart aid to Xinjiang”is one of the important measures to implement the country’s western development strategy.It aims to shorten the gap between higher education in Xinjiang and the eastern region and to...The“counterpart aid to Xinjiang”is one of the important measures to implement the country’s western development strategy.It aims to shorten the gap between higher education in Xinjiang and the eastern region and to maintain the coordinated development of education,economy and society in the eastern and western regions.This article takes the counterpart support of Xinjiang students from the School of Foreign Languages of Jilin Engineering Normal University as an example to explore the problem of the initiative training of Xinjiang students in English learning in our school,mainly from the aspects of the students themselves,the teachers and the entire education and training environment of our school.The angle explains how to help them improve their learning initiative.This article is divided into three parts.The first is the analysis of the connotation of learning initiative;the second is its meaning;the last is how to build the learning initiative of Xinjiang students.展开更多
Chinese,Australian FMs Host Diplomatic and Strategic DialogueOn September 7 Chinese Foreign Minister Wang Yi and his Australian counterpart Julie Bishop co-hosted the second round of China-Australia Diplomatic and Str...Chinese,Australian FMs Host Diplomatic and Strategic DialogueOn September 7 Chinese Foreign Minister Wang Yi and his Australian counterpart Julie Bishop co-hosted the second round of China-Australia Diplomatic and Strategic Dialogue in Sydney.Wang Yi said that bilateral relations have maintained an optimistic momentum.To enhance bilateral ties,展开更多
People doing business in China should try to know how to address their Chinese counter-parts, especially in formal settings so as to better engage with them. Different cultures mean people are addressed differently.
The tribological behaviors of Ti–Ni51.5 at%alloy strengthened by finely dispersed Ni_(4)Ti_(3) particles in reciprocating sliding against GCr15,Al_(2)O_(3),and ZrO_(2) at room temperature were studied.Interestingly,t...The tribological behaviors of Ti–Ni51.5 at%alloy strengthened by finely dispersed Ni_(4)Ti_(3) particles in reciprocating sliding against GCr15,Al_(2)O_(3),and ZrO_(2) at room temperature were studied.Interestingly,the coefficient of friction(COF)suffered a sheer drop(from 0.9 to 0.2)when the aged alloy slid against GCr15 at a frequency of 20 Hz under a 20 N load without lubrication.However,severe‐mild wear transition disappeared when a solutionized alloy was used.Moreover,the COF stabilized at a relatively high level when Al_(2)O_(3) and ZrO_(2) were used as counterparts,although their wear mechanisms showed signs of oxidation.Scanning electron microscopy(SEM)and X‐ray element mappings of the wear scars of the counterparts clearly indicate that the formation of well‐distributed tribo‐layer and material transfer between the ball and disk are pivotal to the severe‐to‐mild wear transition in the aged Ti–Ni51.5 at%alloy/GCr15 friction pair.The higher microhardness and superelasticity of the aged alloy significantly accelerate the material transfer from GCr15 to the disk,forming a glazed protective tribo‐layer containing Fe‐rich oxides.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.51702146)the College Students’Innovation and Entrepreneurship Projects,China(Grant No.201710148000072)Liaoning Province Doctor Startup Fund,China(Grant No.201601325)。
文摘Using ab initio density functional theory calculations, we explore the three most stable structural phases, namely, α,β, and cubic(c) phases, of two-dimensional(2D) antimonene, as well as its isoelectronic counterparts SnTe and InI. We find that the band gap increases monotonically from Sb to SnTe to InI along with an increase in ionicity, independent of the structural phases. The band gaps of this material family cover the entire visible-light energy spectrum, ranging from 0.26 eV to 3.37 eV, rendering them promising candidates for optoelectronic applications. Meanwhile, band-edge positions of these materials are explored and all three types of band alignments can be achieved through properly combining antimonene with its isoelectronic counterparts to form heterostructures. The richness in electronic properties for this isoelectronic material family sheds light on possibilities to tailor the fundamental band gap of antimonene via lateral alloying or forming vertical heterostructures.
文摘In recent years, with museums popularized by various cultural creative products, libraries are unwilling to lag behind. Recently, the National Library Cultural and Creative Artwork Store was officially opened. Meanwhile, the Flagship Store of the National Library Cultural and Creative Union was launched on Tmall. Led by the National Library of China, 116 libraries across the country have "joined hands" to set up online shops, so as to jointly develop cultural creative products.
文摘On July 20th, a signing ceremony between Setcore Group, Egypt represented by Mr. Tamer Nassar-Chairman of Group and the World Trade & Commerce Center, Dongyang-China represented by Mr. Jiang Yuejin-Mayor of Dongyang City was held at the Marriott Hotel in Zamalek-Cairo. This was win-win cooperation and exerted great significances on both sides. In this event, they exchange ideas on the economic issues of common concerned and signed a memorandum of understanding as well.
文摘Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)is a constellation with four instruments(launch date):GECAM-A/B(10 December 2020),GECAM-C(27 July 2022)and GECAM-D(13 March 2024),which are dedicated to monitoring gamma-ray transients in all-sky.The primary science objectives of GECAM include Gamma-Ray Bursts(GRBs),Soft Gamma-ray Repeaters(SGRs),high energy counterparts of Gravitation Wave(GW)and Fast Radio Burst(FRB),Solar Flares(SFLs),as well as Terrestrial Gamma-ray Flashes(TGFs)and Terrestrial Electron Beams(TEBs).A series of observations and research have been made since the launch of GECAM-A/B.GECAM observations provide new insights into these highenergy transients,demonstrating the unique role of GECAM in the“multi-wavelength,multi-messenger”era.
文摘In British Council-managed ELT projects in Chinese universities,Chinese project counterparts areselected from among the English-language teaching staff of the University.They work alongside aBritish Council-recruited lecturer(BCL)in developing whatever it is the project has been set up tocreate:a syllabus,teaching materials,a course,etc.During the lifetime of the project eachcounterpart is sent for a year’s postgraduate training(typically an MA in applied Linguistics)at aBritish university,the rationale being that the combination of training on the job and in the UK willequip them to take over the running of the project and ensure its long-term sustainability.This paperlooks at the staff development of the counterparts prior to their UK training.
基金Project supported by NSFCNational Laboratory of Elemento-Organic Chemistry.
文摘In order to investigate the structure-odor relationship of odoriferous compounds and search for new aroma chemicals, seven acetals of 4-trimethylsilyl-3-cyclohexenone and their carbon counterparts were synthesized by Birch reduction of 4-substituted anisoles and then acetalization. Seven acetals of 4-trimethylsilylcyclohexanone and their carbon counterparts were synthesized similarly. Structures of all new compounds were determined by MS, IR and ~1H NMR, and their characteristic odors were evaluated as well. The characteristic odors of the acetals formed by 4-substituted-3-cyclohexenone and 1, 2-diols are fruity and woody. The acetals formed from 1, 3-diols are woody, and formed with 1, 4-diols are very faint in odor. Odors of acetals of 4-substituted cyclohexanone are all very weak. As a whole, odors of organosilicon compounds are weaker, but somewhat more delicate than their carbon counter- parts.
基金supported in part by NSFC under Grants No.11975046 and No.11575022。
文摘LIGO/Virgo S190814 bv is the first high-probability neutron star–black hole(NSBH)merger candidate,whose gravitational waves(GWs)triggered LIGO/Virgo detectors at21:10:39.012957 UT,14 August 2019.It has a probability>99%of being an NSBH merger,with a low false alarm rate(FAR)of one per 1.559 e+25 years.For an NSBH merger,electromagnetic counterparts(especially short gamma-ray bursts(GRBs))are generally expected.However,no electromagnetic counterpart has been found in the extensive follow-up observing campaign.In the present work,we propose a novel explanation for this null result.In our scenario,LIGO/Virgo S190814 bv is just a GW mirror image of the real NSBH merger which should have been detected before 14 September 2015,but at that time we had no ability to detect its GW signals.The electromagnetic counterparts associated with the real NSBH merger should be found in the archive data before 14 September 2015.In this work,we indeed find nine short GRBs that are possibly electromagnetic counterparts.
基金the General Program of National Science Foundation of China(No.10375066)
文摘Bacillus megaterium BM302 bred by ion-beam implantation produces L-sorbose dehydrogenase accelerative protein (SAP) to accelerate the activity of L-sorbose dehydrogenase (SDH) of Gluconobacter oxydans in the 2-keto-L-gulonic acid (2KLG) fermentation from L-sorbose by the mixed culture of B. megaterium BM302 and G. oxydans. The SAP purified by three chromatographic steps gave 35-fold purification with a yield of 13% and a specific activity of 5.21 units/mg protein. The molecular weight of the purified SAP was about 58 kDa. The SDH accelerative activity of SAP at pH 7 and 50℃ was the highest. Additionally, it retained 60% activity at a pH range of 6.5 ~ 10 and was stable at 20℃ ~ 60℃. After 0.32-unit SAP was added to the single cultured G. oxydans strains, the SDH activity was apparently accelerated and the 2KLG yield of GO29, GO112, GO and GI13 was enhanced 2.1, 3.3, 3.5 and 2.9 folds respectively over that of the strains without the addition of SAP.
基金Supported by the National Nature Science Foundation of China(Nos.21306039,21276060,21276062)the Natural Science Foundation of Hebei Province(B2015202082,B2016202027)the Tianjin City High School Science&Technology Fund Planning Project(20140513)
文摘Cross-linked enzyme aggregates(CLEAs) of nitrile hydratase(NHase) ES-NHT-118 from Escherichia coli were prepared by using ammonium sulfate as precipitating agent followed by cross-linking with dextran polyaldehyde for the first time. In this process, egg white was added as protein feeder for facilitating the formation of CLEAs. The optimal conditions of the immobilization process were determined. Michaelis constants(Km) of free NHase and NHase CLEAs were also determined. The NHase CLEAs exhibited increased stability at varied pH and temperature conditions compared to its free counterpart. When exposed to high concentrations of acrylamide, NHase CLEAs also exhibited effective catalytic activity.
文摘Interprovincial counterpart support is a cooperative system used by local governments to achieve horizontal flow of resources based on cross-regional cooperation.Existing research has mainly focused on governance ef‐ficiency,institutional advantages,and ranking incentives while ignoring the scrambling behavior and opera‐tional mechanisms of local governments formed by ranking incentives and territorial responsibilities.This study selected the Wenchuan earthquake,Yushu earthquake,and COVID-19 as three typical cases.We con‐structed a theoretical framework for competition among provincial local governments and found that competi‐tion in interprovincial disaster counterpart support followed a dual behavioral logic of“striving to be first”and“fear of being last”.Specifically,local governments will choose striving to be first under the logic of time coercion,content games,and territorial responsibility;they will choose fear of being last under the logic of re‐sponsibility avoidance and moral pressure.This type of scrambling-based horizontal competition reflects the logic of local government competition tournaments.This study further revealed the specific processes,mecha‐nisms,and results of horizontal local government competition,which can provide inspiration for cross regional and provincial cooperation.
文摘The wear mechanism of metallic card clothing,used in textile industry,was analyzed.A fast wear test for metallic card clothing racks was developed,which was used as collecting the wear metal particles.The failure type of card clothing was analyzed by the mean of scanning electron microscopy(SEM)and ferro-spectrum technology.The results show that the main wear mechanism of metallic card clothing is low load and high repetition interval fatigue wear caused by friction force between fiber and metal wire teeth.The appropriate quenching microstructure,which improves the wear resistance of the metallic card clothing rack is also discussed.
文摘Eighty three cases of low vision patients (144 eyes) were examined with distant visual aids. The average visual acuity of the 144 eyes before refraction was approximately 0.07, while the counterpart afterwards was about 0.1 (p【0.01), With the 4x monocular focusable aid, acuity improved in 142 eyes out of the 144 eyes. The combined use of clip-on distance aid and the spectacle reading aid was observed to be especially suitable for partially sighted students.The mean MEF of 142 eyes was 0.9435±0.2068. The paired T-test between the difference of actual magnification and theoretical magnification was not significant at the 5% level. The factors contributing to the variance of MEF were discussed.
文摘In the blood fluke Schistosoma mansoni a functionally active, monomeric, phospholipid hydroperoxide glutathione peroxidase (PHGPx) has been purified and characterized. This enzyme contains a catalytically active selenocysteine. The protein has been shown to be the product of a cloned gene, previously referred to as a glutathione peroxidase gene. S. mansoni PHGPx has been found 5 times more abundant in female than in male worm extract. As in vertebrate PHGPx, homology alignment indicates that the residues involved in the glutathione binding by the tetrameric cellular glutathione peroxidase are mutated in the S. mansoni enzyme. Thus, this aspect appears a landmark of the PHGPx-type of glutathione peroxidases,which might be of functional relevance
文摘The use of credit default swaps (CDSs) has become increasingly popular over time. Between 2002 and 2007, gross notional amounts outstanding grew from below S2 trillion to nearly S60 trillion. The recent crisis has revealed several shortcomings in CDS market practices and structure. In addition, management of counterparty risk has proved insufficient, as has in some instances the settlement of contracts following a credit event. However, past problems should not distract from the potential benefits of these instruments. In particular, CDSs help complete markets, as they provide an effective means to hedge and trade credit risk. CDSs allow financial institutions to better manage their exposures, and investors benefit from an enhanced investment universe. The purpose of this paper is to present a complete and practical exposition of the CDS market and to explore how the development of the CDS market has played an important role in the credit risk markets. Currently, the CDS market is transforming into a more stable system. Various measures are being put in place to help enhance market transparency and mitigate operational and systemic risk. In particular, central counterparties have started to operate, which will eventually lead to an improved management of individual as well as system-wide risks.
基金financially supported by the"13th Five-Year Plan"of Education Science in Jilin Province in 2017 as one of the research results of"Study of the initiative in English learning of the Xinjiang students assisted by other universities"(GHI 170652).
文摘The“counterpart aid to Xinjiang”is one of the important measures to implement the country’s western development strategy.It aims to shorten the gap between higher education in Xinjiang and the eastern region and to maintain the coordinated development of education,economy and society in the eastern and western regions.This article takes the counterpart support of Xinjiang students from the School of Foreign Languages of Jilin Engineering Normal University as an example to explore the problem of the initiative training of Xinjiang students in English learning in our school,mainly from the aspects of the students themselves,the teachers and the entire education and training environment of our school.The angle explains how to help them improve their learning initiative.This article is divided into three parts.The first is the analysis of the connotation of learning initiative;the second is its meaning;the last is how to build the learning initiative of Xinjiang students.
文摘Chinese,Australian FMs Host Diplomatic and Strategic DialogueOn September 7 Chinese Foreign Minister Wang Yi and his Australian counterpart Julie Bishop co-hosted the second round of China-Australia Diplomatic and Strategic Dialogue in Sydney.Wang Yi said that bilateral relations have maintained an optimistic momentum.To enhance bilateral ties,
文摘People doing business in China should try to know how to address their Chinese counter-parts, especially in formal settings so as to better engage with them. Different cultures mean people are addressed differently.
基金This work was supported by the National Natural Science Foundation of China(51673205)the Key Research Program of Frontier Science,Chinese Academy of Sciences(QYZDJ‐SSW‐SLH056)the National Basic Research Program of China(2015CB057502).
文摘The tribological behaviors of Ti–Ni51.5 at%alloy strengthened by finely dispersed Ni_(4)Ti_(3) particles in reciprocating sliding against GCr15,Al_(2)O_(3),and ZrO_(2) at room temperature were studied.Interestingly,the coefficient of friction(COF)suffered a sheer drop(from 0.9 to 0.2)when the aged alloy slid against GCr15 at a frequency of 20 Hz under a 20 N load without lubrication.However,severe‐mild wear transition disappeared when a solutionized alloy was used.Moreover,the COF stabilized at a relatively high level when Al_(2)O_(3) and ZrO_(2) were used as counterparts,although their wear mechanisms showed signs of oxidation.Scanning electron microscopy(SEM)and X‐ray element mappings of the wear scars of the counterparts clearly indicate that the formation of well‐distributed tribo‐layer and material transfer between the ball and disk are pivotal to the severe‐to‐mild wear transition in the aged Ti–Ni51.5 at%alloy/GCr15 friction pair.The higher microhardness and superelasticity of the aged alloy significantly accelerate the material transfer from GCr15 to the disk,forming a glazed protective tribo‐layer containing Fe‐rich oxides.