2MASS(Two Micron All Sky Survey)以相当高的内部一致性和精确度在近红外波段对整个天空进行了巡天观测,并通过数据处理把原始数据转变为对天文学有用的图像、星等和位置的列表。较详细介绍了2MASS的科学意义、巡天成果、数据特征以及...2MASS(Two Micron All Sky Survey)以相当高的内部一致性和精确度在近红外波段对整个天空进行了巡天观测,并通过数据处理把原始数据转变为对天文学有用的图像、星等和位置的列表。较详细介绍了2MASS的科学意义、巡天成果、数据特征以及利用2MASS观测数据所开展的部分工作。展开更多
Electrolytic Zn-MnO_(2)batteries arepromising candidates for safe and sustainable energystorage owing to their high voltage,environmentalbenignity,and cost-effectiveness.However,practicalapplications are hindered by t...Electrolytic Zn-MnO_(2)batteries arepromising candidates for safe and sustainable energystorage owing to their high voltage,environmentalbenignity,and cost-effectiveness.However,practicalapplications are hindered by the poor conductivity andthe irreversible dissolution of conventionalε-MnO_(2)deposits.Herein,we report a scalable semisolid slurryelectrode architecture that enables stable MnO_(2)deposition/dissolution using a three-dimensional percolatingnetwork of carbon nanotubes(CNTs)as both conductivematrix and deposition host.The slurry systempromotes the formation of highly conductiveγ-MnO_(2)owing to enhanced charge transfer kinetics,enablingoverall dissolution rather than the localized separationtypically seen in traditional electrodes.The Zn-MnO_(2)slurry cell exhibits a reversible areal capacity approaching 60 mAh cm^(-2).Moreover,theflowable nature of the slurry allows electrochemically inactive MnO_(2)formed during dissolution to be reconnected and reactivated by CNTs inthe rheological network,ensuring deep utilization and cycling stability.This work establishes a slurry electrode strategy to improve electrolyticMnO_(2)reactions and offers a viable pathway toward renewable aqueous batteries for grid-scale applications.展开更多
The effect of(CaO+SiO_(2))mass ratio on high-Ti vanadium titanomagnetite sintering was systematically studied at the fixed basicity(CaO/SiO_(2))of 2.0.The results show that sinter matrix strength is improved with(CaO+...The effect of(CaO+SiO_(2))mass ratio on high-Ti vanadium titanomagnetite sintering was systematically studied at the fixed basicity(CaO/SiO_(2))of 2.0.The results show that sinter matrix strength is improved with(CaO+SiO_(2))mass ratio while the total iron content is reduced.Thermodynamic analysis indicates that the increase in(CaO+SiO_(2))mass ratio from 15.0 to 22.5 wt.%contributes to the formation of liquid phase,especially silico-ferrite of calcium and aluminum(SFCA).In addition,the formation of perovskite is inhibited and liquid phase fluidity is improved.The porosity of sinter matrix is reduced by 34.5%and SFCA amount is increased by 47.2%when(CaO+SiO_(2))mass ratio is increased from 15.0 to 18.0 wt.%.With the further increase in(CaO+SiO_(2))mass ratio,the structure of sinter matrix is too dense and the improved extent of SFCA amount is increasingly low.The appropriate(CaO+SiO_(2))mass ratio should be 18.0 wt.%overall.Under this condition,sinter matrix strength is greatly improved by over 13.5%compared with the base case and the total iron content can be maintained at about 49 wt.%.展开更多
Objectives:Proteasomes,multi-subunit proteases,are key actors of cellular protein catabolism and a number of regulatory processes.The detection of subtle proteasome functioning in tumors may contribute to our understa...Objectives:Proteasomes,multi-subunit proteases,are key actors of cellular protein catabolism and a number of regulatory processes.The detection of subtle proteasome functioning in tumors may contribute to our understanding of the mechanisms of cancer development.The current study aimed to identify the role of low molecular mass protein 2(LMP2),a proteasome immune subunit,in the development of mouse colon 26(C26)adenocarcinoma.Methods:The functions of the LMP2 subunit in tumor development in Balb/c mice were studied using its irreversible inhibitor KZR-504.LMP2 activity was detected by the hydrolysis of the fluorogenic substrate Ac-Pro-Ala-Leu-AMC.Western blotting and Quantitative Reverse Transcription Polymerase Chain Reaction(qRT-PCR)were used.We applied fluorescent tests for cell proliferation and apoptosis.M2 macrophages were obtained by polarization of mouse bone marrow-derived macrophages using the corresponding cytokines.Results:KZR-504 showed high specificity only for the LMP2 subunit and had no negative effect on C26 cells in culture.However,KZR-504 suppressed the formation of tumor conglomerates(by 74%,p<0.001)after C26 cell transplantation in vivo,inhibited the expression of chitinase-<3-like protein 3(Chil3)gene(by 90%,p<0.001),a key marker of immunosuppressive M2 macrophages,in the tumor<microenvironment,and reduced the tumor weight compared to the control(by 48%,p<0.01).KZR-504 also suppressed<the expression of Chil3(by 68%,p<0.05)and arginase-1(Arg1)(by 90%,p<0.001),another marker gene,in M2<<macrophages and violated M0-M2 macrophage polarization in culture.Conclusion:We discovered earlier unknown functions of the proteasome LMP2 subunit to facilitate the formation of tumor conglomerates and maintain Chil3 and Arg1 expression in immunosuppressive M2 macrophages.Our work demonstrates that the proteasome LMP2 subunit can be a target for antitumor treatment.展开更多
To reveal the complex crude oil-CO_(2) interaction mechanism and oil mobilization behavior during CO_(2) huff-n-puff in shale-type shale oil reservoirs,CO_(2) huff-n-puff experiments with on-line nuclear magnetic reso...To reveal the complex crude oil-CO_(2) interaction mechanism and oil mobilization behavior during CO_(2) huff-n-puff in shale-type shale oil reservoirs,CO_(2) huff-n-puff experiments with on-line nuclear magnetic resonance monitoring were conducted on Gulong shale cores,combined with the prediction model of CO_(2) dynamic diffusion coefficient,the flow mechanism and factors influencing oil mobilization during CO_(2) huff and puff in Gulong shale oil reservoirs are studied,and the diffusion and mass transfer behavior of CO_(2) in shale is investigated.The results show that at the injection stage,CO_(2) invades into macropores near the injection end,and drives part of the crude oil to micropores in the deep part of the core.At the shut-in stage,the crude oil gradually reflows to macropores near the injection end and is redistributed in the core.At the production stage,the oil mobilization zone is gradually expanded from the production end(injection end)to the deep part of the core.The contribution ratio of produced oil from macropores and micropores is about 8︰3 after production.The diffusion coefficient of CO_(2) in shale porous media gradually decreases with the advance of diffusion front at shut-in stage.The better the porosity and permeability of core samples,the higher the CO_(2) concentration at diffusion front,the greater the CO_(2) diffusion coefficient,and the slower the diffusion decline rate is.Increasing the huff and puff cycles could effectively enhance oil displacement efficiency,though its impact on the crude oil mobilization zone remains insignificant.The crude oil in small pores of the small layer with undeveloped laminae is difficult to be produced during CO_(2) huff and puff,and the oil recovery is only 12.72%.The crude oil in macropores and micropores of the small layer with developed laminae can be effectively mobilized during CO_(2) huff and puff,and the oil recovery can reach 39.11%.展开更多
建立导航星星表是星敏感器设计的重点工作。根据全天时星敏感器工作特点,选用2M ASS(tw o micron all sky survey)星表为原始恒星数据源。在分析其数据结构的基础上,讨论选用双星为导航星,计算等效星等和位置的方法。详细描述处理2MASS...建立导航星星表是星敏感器设计的重点工作。根据全天时星敏感器工作特点,选用2M ASS(tw o micron all sky survey)星表为原始恒星数据源。在分析其数据结构的基础上,讨论选用双星为导航星,计算等效星等和位置的方法。详细描述处理2MASS星表,构建全天时星敏感器导航星星库的过程。结果表明,相同极限星等条件下,近红外波段导航星星数远多于可见光波段,全天时星敏感器相机可选用较小口径或较小视场系统。展开更多
This paper reports results from the first long-term BV(RI)c photometric CCD observations of three variable pre-main-sequence stars collected during the period from February 2007 to January 2020. The investigated stars...This paper reports results from the first long-term BV(RI)c photometric CCD observations of three variable pre-main-sequence stars collected during the period from February 2007 to January 2020. The investigated stars are located in the field of the PMS star V733 Cep within the Cepheus OB3 association. All stars from our study show rapid photometric variability in all-optical passbands. In this paper, we describe and discuss the photometric behavior of these stars and the possible reasons for their variability. In the light variation of two of the stars, we found periodicity.展开更多
The photodissociation dynamics of 2-iodotoluene following excitation at 266 nm have been investigated employing femtosecond time-resolved mass spectrometry. The photofragments are detected by multiphoton ionization us...The photodissociation dynamics of 2-iodotoluene following excitation at 266 nm have been investigated employing femtosecond time-resolved mass spectrometry. The photofragments are detected by multiphoton ionization using an intense laser field centered at 800 nm. A dissociation time of 3804-50 fs was measured from the rising time of the co-fragments of toluene radical （C7H7） and iodine atom （I）, which is attributed to the averaged time needed for the C-I bond breaking for the simultaneously excited nσ and ππ＊ states by 266 nm pump light. In addition, a probe light centered at 298.23 nm corresponding to resonance wavelength of ground-state iodine atom is used to selectively ionize ground-state iodine atoms generated from the dissociation of initially populated hσ＊ and ππ＊ states. And a rise time of 4004-50 fs is extracted from the fitting of time-dependent I＋ transient, which is in agreement with the dissociation time obtained by multiphoton ionization with 800 nm, suggesting that the main dissociative products are ground-state iodine atoms.展开更多
The reactive surface area, an important parameter controlling mineral reactions, affects the amount of mineralization trapping of CO2 which affects the long-term CO2 storage. The effect of the reactive surface area on...The reactive surface area, an important parameter controlling mineral reactions, affects the amount of mineralization trapping of CO2 which affects the long-term CO2 storage. The effect of the reactive surface area on the mineralization trapping of CO2 was numerically simulated for CO2 storage in saline aquifers. Three kinds of minerals, including anorthite, calcite and kaolinite, are involved in the mineral reactions. This paper models the relationship between the specific surface area and the grain diameter of anorthite based on experimental data from literature （Brantley and Mellott, 2000）. When the reactive surface areas of anorthite and calcite decrease from 838 to 83.8 m^2/m^3, the percentage of mineralization trapping of CO： after 500 years decreases from 11.8% to 0.65%. The amount of dissolved anorthite and the amounts of precipitated kaolinite and calcite decrease significantly when the reactive surface areas ofanorthite and calcite decrease from 838 to 83.8 m2/m3. Calcite is initially dissolved in the brine and then precipitates during the geochemical reactions between CO2-H20 and the minerals. Different reactive surface areas of anorthite and calcite lead to different times from dissolution to precipitation. The pH of the brine decreases with decreasing reactive surface areas of anorthite and calcite which influences the acidity of the saline aquifer. The gas saturation between the upper and lower parts of the saline aquifer increases with decreasing reactive surface areas of anorthite and calcite. The mass density distribution of brine solution shows that the CO2^＋brine solution region increases with decreasing reactive surface areas ofanorthite and calcite.展开更多
Surface tension of calcium aluminate refining slag was measured by the Slide method at 1823 K.Based on different levels of the MgO content and the mass ratio of CaO to Al_2O_3,the effects of MgO content and the mass r...Surface tension of calcium aluminate refining slag was measured by the Slide method at 1823 K.Based on different levels of the MgO content and the mass ratio of CaO to Al_2O_3,the effects of MgO content and the mass ratio of CaO to Al_2O_3 on surface tension were investigated.The results indicate that surface tension decreased with increasing MgO content(from 0 to 4.86%),followed by an increase with further increasing MgO content up to 11.33%.The trend that surface tension changed with the mass ratio of CaO to Al_2O_3 was the same as the trend that surface tension changed with the MgO content.The surface tension was varied from 0.617 N/m to 0.710 N/m,for the mass ratio of CaO to Al_2O_3 varying between 0.60 and 1.28.An attempt was made to estimate surface tension of CaO-Al_2O_3-MgO slag and its sub-system,and the application showed that the model worked well.展开更多
The dissolution of alumina-based refractory ceramics in CaO-Al2O3-SiO_(2)slag melts was performed based on the in-situ observation system of an ultra-high-temperature laser confocal microscope,and the effect of the Ca...The dissolution of alumina-based refractory ceramics in CaO-Al2O3-SiO_(2)slag melts was performed based on the in-situ observation system of an ultra-high-temperature laser confocal microscope,and the effect of the CaO/SiO_(2)slag mass ratio(C/S ratio)on the dissolution rate of alumina-based refractory ceramics was investigated.The results indicate that the dissolution rate increases with an increase of the C/S ratio and is mainly controlled by diffusion.During the early stage of dissolution,for all C/S ratios,the dissolution process conforms to the classical invariant interface approximation model.During the later stage of dissolution,when the C/S ratio is≥6,the dissolution process is significantly different from the model above because of the formation of a thick interfacial layer,which can be explained by dissolution kinetics.展开更多
The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was investigated.The results show that with the increase in Al...The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was investigated.The results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and Al-O-Si.Furthermore,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of slag.The increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the slag.The slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.展开更多
Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during transportation.The welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local...Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during transportation.The welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local corrosion of welded joints.A high wall shear stress(WsS)experimental setup was established to conduct the online electrochemical corrosion test.The influence of WRH sizes on local corrosion of welded joints was studied at different flow rates.The electrochemical signals of the local corrosion of X80 welded joints at different flow rates were monitored in real time using electrochemical impedance spectroscopy and wire beam microelectrode.In addition,the corrosion products composition and properties were analyzed.The results show that the micro-turbulent flow fields induced by the WRHs can enhance ion mass transfer near the welded joints.The corrosion products on the WRH surface also present different microscopic morphologies at different flow rates.In strong flow fields,the locally enhanced wsS can peel off the dense corrosion product partially,leading to the electrochemical distribution of large cathode and small anode,which accelerates the occurrence and development processes of the local corrosion of welded joints.The scientific guidelines for the corrosion protection of long-distance oil and gas pipelines can be potentially provided.展开更多
Osteogenesis imperfecta（OI） comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications...Osteogenesis imperfecta（OI） comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI,many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B（ACVR2B） in a mouse model of type Ⅲ OI（oim）. Treatment of 12-week-old oim mice with ACVR2 B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy,wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system.展开更多
In this study, seven alkaloids were detected in Wu-tou decoction using ultra performance liquid chromatography coupled with tandem mass spectrometry （UPLC-MSn）. The aim of this study was to investigate the effect of...In this study, seven alkaloids were detected in Wu-tou decoction using ultra performance liquid chromatography coupled with tandem mass spectrometry （UPLC-MSn）. The aim of this study was to investigate the effect of Fritillariae Cirrhosae Bulbus, Fritillariae Thunbergii Bulbus, Pinelliae Rhizoma in different ratios with Wu-tou decoction （2：1, 1：1, 1：2） by measuring the therapeutic effects in Wu-tou decoction of main seven alkaloids including benzoylaconitine （BA）, benzoylmesaconitine （BM）, benzoylhypaconitine （BH）, hypaconitine （HA）, fuziline （FU）, niaolin （NE） and deoxyaconitine （DA）. The permeability of aconitum alkaloids extract through a Caco-2 cell monolayer was analyzed in the absence and presence of Fritillariae Cirrhosae Bulbus, Fritillariae Thunbergii Bulbus, and Pinelliae Rhizoma, respectively. The results showed that Pinelliae Rhizoma could reduce the absorption of the alkaloids and increase the excretion of the alkaloids, which would attenuate the therapeutic effects of Wu-tou decoction. Therefore, Pinelliae Rhizoma is an incompatible herb of Wu-tou decoction because of the inhibition of the absorption of alkaloids in the intestine. And that Fritillariae Cirrhosae Bulbus and Fritillariae rhunbergii Bulbus showed the effects to improve the permeability of the alkaloids in Wu-tou decoction. These effects of these two herbs were similar, but the former was stronger than the latter, which most likely is due to the fact that the compositions of these two traditional Chinese medicines are similar. The in vitro data suggests that the compounds such as fritillary presented in alkaloids in the formula maybe improve the therapeutic function caused by the increased bioavailability of alkaloids in intestine.展开更多
The metaphosphate anion, PO_3, was detected in the negative-ion chemicalionization mass spectra of 2,6,7-trioxa-1-phospbabicyclo[2.2. 2] octane-1-oxides.
Efficient alkaline hydrogen evolution reaction(HER)catalysts are critical for anion exchange membrane water electrolysis(AEMWE).However,the intrinsic scaling relationship between water dissociation and OH desorption f...Efficient alkaline hydrogen evolution reaction(HER)catalysts are critical for anion exchange membrane water electrolysis(AEMWE).However,the intrinsic scaling relationship between water dissociation and OH desorption fundamentally impedes designing catalysts requiring concurrent superior water dissociation and facile OH desorption.Here,we engineer a superhydrophilic Ru/Cr_(2)O_(3) heterostructured electrocatalyst through in situ confinement of Ru nanoparticles(5-10 nm)within a Cr_(2)O_(3) matrix.Acting as a Lewis acid,the Cr_(2)O_(3) component provides alternative sites for water dissociation,accelerating the Volmer step kinetics and downshifting the Ru d-band center via interfacial charge transfer,while simultaneously adsorbing OH-to form a surface-bound Lewis base that repels excess OH-from Ru sites,thereby suppressing hydroxyl over-adsorption.Concurrently,the superhydrophilic surface architecture promotes efficient hydrogen bubble release,thereby reducing mass transport resistance.As a result,the Ru/Cr_(2)O_(3) heterostructured electrocatalyst exhibits an ultralow overpotential of 36.7 mV at 10 mA cm^(-2) and a Tafel slope of 33.2 mV dec^(-1).Integrated into an AEMWE device,the electrode delivers500 mA cm^(-2) for 2000 h in 1.0 M KOH,underscoring its industrial viability(hydrogen production energy consumption per cubic meter(EW):3.94 kW h m^(-3);electricity-to-hydrogen energy conversion efficiency(η_(ETH)):89%@80℃).展开更多
基金supported by the National Natural Science Foundation of China(No.22109181,U24A2060,22279023,and 22309031)the National Key R&D Program of China(2024YFE0101100)+6 种基金the Hunan Provincial Science and Technology Plan Projects of China(No.2017TP1001)the Hunan Provincial Natural Science Foundation of China(No.2025JJ40011)the Fundamental Research Funds for the Central Universities(20720250005)the Science and Technology Commission of Shanghai Municipality(25DZ3002901,2024ZDSYS02,25PY2600100)the Shanghai Pilot Program for Basic Research-Fudan University 21TQ1400100(25TQ012)the AI for Science Foundation of Fudan University(FudanX24A1035)the National Research Foundation,Singapore,under its Singapore-China Joint Flagship Project(Clean Energy).
文摘Electrolytic Zn-MnO_(2)batteries arepromising candidates for safe and sustainable energystorage owing to their high voltage,environmentalbenignity,and cost-effectiveness.However,practicalapplications are hindered by the poor conductivity andthe irreversible dissolution of conventionalε-MnO_(2)deposits.Herein,we report a scalable semisolid slurryelectrode architecture that enables stable MnO_(2)deposition/dissolution using a three-dimensional percolatingnetwork of carbon nanotubes(CNTs)as both conductivematrix and deposition host.The slurry systempromotes the formation of highly conductiveγ-MnO_(2)owing to enhanced charge transfer kinetics,enablingoverall dissolution rather than the localized separationtypically seen in traditional electrodes.The Zn-MnO_(2)slurry cell exhibits a reversible areal capacity approaching 60 mAh cm^(-2).Moreover,theflowable nature of the slurry allows electrochemically inactive MnO_(2)formed during dissolution to be reconnected and reactivated by CNTs inthe rheological network,ensuring deep utilization and cycling stability.This work establishes a slurry electrode strategy to improve electrolyticMnO_(2)reactions and offers a viable pathway toward renewable aqueous batteries for grid-scale applications.
基金supported by National Natural Science Foundation of China(No.52304344)Postdoctoral Science Foundation of China(No.2024T171095)Cooperation Project of Pangang Group.Author information。
文摘The effect of(CaO+SiO_(2))mass ratio on high-Ti vanadium titanomagnetite sintering was systematically studied at the fixed basicity(CaO/SiO_(2))of 2.0.The results show that sinter matrix strength is improved with(CaO+SiO_(2))mass ratio while the total iron content is reduced.Thermodynamic analysis indicates that the increase in(CaO+SiO_(2))mass ratio from 15.0 to 22.5 wt.%contributes to the formation of liquid phase,especially silico-ferrite of calcium and aluminum(SFCA).In addition,the formation of perovskite is inhibited and liquid phase fluidity is improved.The porosity of sinter matrix is reduced by 34.5%and SFCA amount is increased by 47.2%when(CaO+SiO_(2))mass ratio is increased from 15.0 to 18.0 wt.%.With the further increase in(CaO+SiO_(2))mass ratio,the structure of sinter matrix is too dense and the improved extent of SFCA amount is increasingly low.The appropriate(CaO+SiO_(2))mass ratio should be 18.0 wt.%overall.Under this condition,sinter matrix strength is greatly improved by over 13.5%compared with the base case and the total iron content can be maintained at about 49 wt.%.
基金funded by the Government program of basic research in Koltzov Institute of Developmental Biology of the Russian Academy of Sciences,number 0088-2024-0009the Ministry of Science and Higher Education of the Russian Federation,project number 075-15-2020-773(NPS).
文摘Objectives:Proteasomes,multi-subunit proteases,are key actors of cellular protein catabolism and a number of regulatory processes.The detection of subtle proteasome functioning in tumors may contribute to our understanding of the mechanisms of cancer development.The current study aimed to identify the role of low molecular mass protein 2(LMP2),a proteasome immune subunit,in the development of mouse colon 26(C26)adenocarcinoma.Methods:The functions of the LMP2 subunit in tumor development in Balb/c mice were studied using its irreversible inhibitor KZR-504.LMP2 activity was detected by the hydrolysis of the fluorogenic substrate Ac-Pro-Ala-Leu-AMC.Western blotting and Quantitative Reverse Transcription Polymerase Chain Reaction(qRT-PCR)were used.We applied fluorescent tests for cell proliferation and apoptosis.M2 macrophages were obtained by polarization of mouse bone marrow-derived macrophages using the corresponding cytokines.Results:KZR-504 showed high specificity only for the LMP2 subunit and had no negative effect on C26 cells in culture.However,KZR-504 suppressed the formation of tumor conglomerates(by 74%,p<0.001)after C26 cell transplantation in vivo,inhibited the expression of chitinase-<3-like protein 3(Chil3)gene(by 90%,p<0.001),a key marker of immunosuppressive M2 macrophages,in the tumor<microenvironment,and reduced the tumor weight compared to the control(by 48%,p<0.01).KZR-504 also suppressed<the expression of Chil3(by 68%,p<0.05)and arginase-1(Arg1)(by 90%,p<0.001),another marker gene,in M2<<macrophages and violated M0-M2 macrophage polarization in culture.Conclusion:We discovered earlier unknown functions of the proteasome LMP2 subunit to facilitate the formation of tumor conglomerates and maintain Chil3 and Arg1 expression in immunosuppressive M2 macrophages.Our work demonstrates that the proteasome LMP2 subunit can be a target for antitumor treatment.
基金Supported by the National Natural Science Foundation of China(520743198)Scientific and Technological Problems Tackling Project of Heilongjiang Province(DQYT-2022-JS-761).
文摘To reveal the complex crude oil-CO_(2) interaction mechanism and oil mobilization behavior during CO_(2) huff-n-puff in shale-type shale oil reservoirs,CO_(2) huff-n-puff experiments with on-line nuclear magnetic resonance monitoring were conducted on Gulong shale cores,combined with the prediction model of CO_(2) dynamic diffusion coefficient,the flow mechanism and factors influencing oil mobilization during CO_(2) huff and puff in Gulong shale oil reservoirs are studied,and the diffusion and mass transfer behavior of CO_(2) in shale is investigated.The results show that at the injection stage,CO_(2) invades into macropores near the injection end,and drives part of the crude oil to micropores in the deep part of the core.At the shut-in stage,the crude oil gradually reflows to macropores near the injection end and is redistributed in the core.At the production stage,the oil mobilization zone is gradually expanded from the production end(injection end)to the deep part of the core.The contribution ratio of produced oil from macropores and micropores is about 8︰3 after production.The diffusion coefficient of CO_(2) in shale porous media gradually decreases with the advance of diffusion front at shut-in stage.The better the porosity and permeability of core samples,the higher the CO_(2) concentration at diffusion front,the greater the CO_(2) diffusion coefficient,and the slower the diffusion decline rate is.Increasing the huff and puff cycles could effectively enhance oil displacement efficiency,though its impact on the crude oil mobilization zone remains insignificant.The crude oil in small pores of the small layer with undeveloped laminae is difficult to be produced during CO_(2) huff and puff,and the oil recovery is only 12.72%.The crude oil in macropores and micropores of the small layer with developed laminae can be effectively mobilized during CO_(2) huff and puff,and the oil recovery can reach 39.11%.
文摘建立导航星星表是星敏感器设计的重点工作。根据全天时星敏感器工作特点,选用2M ASS(tw o micron all sky survey)星表为原始恒星数据源。在分析其数据结构的基础上,讨论选用双星为导航星,计算等效星等和位置的方法。详细描述处理2MASS星表,构建全天时星敏感器导航星星库的过程。结果表明,相同极限星等条件下,近红外波段导航星星数远多于可见光波段,全天时星敏感器相机可选用较小口径或较小视场系统。
基金partly supported by the Bulgarian Ministry of Education and Science under the National Program for Research“Young Scientists and Postdoctoral Students”partial support by grant DN 18-13/2017 from the Bulgarian National Science Fund。
文摘This paper reports results from the first long-term BV(RI)c photometric CCD observations of three variable pre-main-sequence stars collected during the period from February 2007 to January 2020. The investigated stars are located in the field of the PMS star V733 Cep within the Cepheus OB3 association. All stars from our study show rapid photometric variability in all-optical passbands. In this paper, we describe and discuss the photometric behavior of these stars and the possible reasons for their variability. In the light variation of two of the stars, we found periodicity.
基金This work was supported by the National Basic Research Program of China （973 Program） （No.2013CB922200） and the National Natural Science Foundation of China （No.91121006, No.21273274, No.21173256, and No.21303255）.
文摘The photodissociation dynamics of 2-iodotoluene following excitation at 266 nm have been investigated employing femtosecond time-resolved mass spectrometry. The photofragments are detected by multiphoton ionization using an intense laser field centered at 800 nm. A dissociation time of 3804-50 fs was measured from the rising time of the co-fragments of toluene radical （C7H7） and iodine atom （I）, which is attributed to the averaged time needed for the C-I bond breaking for the simultaneously excited nσ and ππ＊ states by 266 nm pump light. In addition, a probe light centered at 298.23 nm corresponding to resonance wavelength of ground-state iodine atom is used to selectively ionize ground-state iodine atoms generated from the dissociation of initially populated hσ＊ and ππ＊ states. And a rise time of 4004-50 fs is extracted from the fitting of time-dependent I＋ transient, which is in agreement with the dissociation time obtained by multiphoton ionization with 800 nm, suggesting that the main dissociative products are ground-state iodine atoms.
基金supported by the National Natural Science Foundation of China (Grant No. 50906043)the Tsinghua University Initiative Scientific Research Program(2009THZ02232)The first author did this study while at Geoscience Australia sponsored by CAGS (China-Australia Geological Storage of CO2Project)
文摘The reactive surface area, an important parameter controlling mineral reactions, affects the amount of mineralization trapping of CO2 which affects the long-term CO2 storage. The effect of the reactive surface area on the mineralization trapping of CO2 was numerically simulated for CO2 storage in saline aquifers. Three kinds of minerals, including anorthite, calcite and kaolinite, are involved in the mineral reactions. This paper models the relationship between the specific surface area and the grain diameter of anorthite based on experimental data from literature （Brantley and Mellott, 2000）. When the reactive surface areas of anorthite and calcite decrease from 838 to 83.8 m^2/m^3, the percentage of mineralization trapping of CO： after 500 years decreases from 11.8% to 0.65%. The amount of dissolved anorthite and the amounts of precipitated kaolinite and calcite decrease significantly when the reactive surface areas ofanorthite and calcite decrease from 838 to 83.8 m2/m3. Calcite is initially dissolved in the brine and then precipitates during the geochemical reactions between CO2-H20 and the minerals. Different reactive surface areas of anorthite and calcite lead to different times from dissolution to precipitation. The pH of the brine decreases with decreasing reactive surface areas of anorthite and calcite which influences the acidity of the saline aquifer. The gas saturation between the upper and lower parts of the saline aquifer increases with decreasing reactive surface areas of anorthite and calcite. The mass density distribution of brine solution shows that the CO2^＋brine solution region increases with decreasing reactive surface areas ofanorthite and calcite.
基金Project(51204115)supported by the National Natural Science Foundation of ChinaProject(BK20130308)supported by the Basic Research Program of Jiangsu Province,ChinaProject(2014M561710)supported by China Postdoctoral Science Foundation
文摘Surface tension of calcium aluminate refining slag was measured by the Slide method at 1823 K.Based on different levels of the MgO content and the mass ratio of CaO to Al_2O_3,the effects of MgO content and the mass ratio of CaO to Al_2O_3 on surface tension were investigated.The results indicate that surface tension decreased with increasing MgO content(from 0 to 4.86%),followed by an increase with further increasing MgO content up to 11.33%.The trend that surface tension changed with the mass ratio of CaO to Al_2O_3 was the same as the trend that surface tension changed with the MgO content.The surface tension was varied from 0.617 N/m to 0.710 N/m,for the mass ratio of CaO to Al_2O_3 varying between 0.60 and 1.28.An attempt was made to estimate surface tension of CaO-Al_2O_3-MgO slag and its sub-system,and the application showed that the model worked well.
基金supported by the National Natural Science Foundation of China(52272022)the Special Project of Central Government for Local Science and Technology Development of Hubei Province(2019ZYYD076)the Innovation and Entrepreneurship Fund of Wuhan University of Science and Technology(D202202171045002669).
文摘The dissolution of alumina-based refractory ceramics in CaO-Al2O3-SiO_(2)slag melts was performed based on the in-situ observation system of an ultra-high-temperature laser confocal microscope,and the effect of the CaO/SiO_(2)slag mass ratio(C/S ratio)on the dissolution rate of alumina-based refractory ceramics was investigated.The results indicate that the dissolution rate increases with an increase of the C/S ratio and is mainly controlled by diffusion.During the early stage of dissolution,for all C/S ratios,the dissolution process conforms to the classical invariant interface approximation model.During the later stage of dissolution,when the C/S ratio is≥6,the dissolution process is significantly different from the model above because of the formation of a thick interfacial layer,which can be explained by dissolution kinetics.
基金supported by the National Natural Science Foundation of China(No.52374409)the National Key Research and Development Program of China(No.2022YFB3504304).
文摘The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was investigated.The results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and Al-O-Si.Furthermore,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of slag.The increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the slag.The slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.
基金support from the National Natural Science Foundation of China(Nos.52206199,42176209,51979282,and 41676071)the Natural Science Foundation of Shandong Province(No.ZR2021MD064).
文摘Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during transportation.The welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local corrosion of welded joints.A high wall shear stress(WsS)experimental setup was established to conduct the online electrochemical corrosion test.The influence of WRH sizes on local corrosion of welded joints was studied at different flow rates.The electrochemical signals of the local corrosion of X80 welded joints at different flow rates were monitored in real time using electrochemical impedance spectroscopy and wire beam microelectrode.In addition,the corrosion products composition and properties were analyzed.The results show that the micro-turbulent flow fields induced by the WRHs can enhance ion mass transfer near the welded joints.The corrosion products on the WRH surface also present different microscopic morphologies at different flow rates.In strong flow fields,the locally enhanced wsS can peel off the dense corrosion product partially,leading to the electrochemical distribution of large cathode and small anode,which accelerates the occurrence and development processes of the local corrosion of welded joints.The scientific guidelines for the corrosion protection of long-distance oil and gas pipelines can be potentially provided.
基金supported by NIAMS,of the National Institutes of Health,under award numbers R01AR062074 (to DJD) and R01AR060636 (to S-JL)the Harry Headley Charitable and Research Foundation,Punta Gorda,FL(to ELG-L)
文摘Osteogenesis imperfecta（OI） comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI,many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B（ACVR2B） in a mouse model of type Ⅲ OI（oim）. Treatment of 12-week-old oim mice with ACVR2 B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy,wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system.
基金supported by the National Natural Sciences Foundation of China(No.81274046)National Basic Research Program of China("973 Program")(Nos.2011CB505300, 2011CB505305)
文摘In this study, seven alkaloids were detected in Wu-tou decoction using ultra performance liquid chromatography coupled with tandem mass spectrometry （UPLC-MSn）. The aim of this study was to investigate the effect of Fritillariae Cirrhosae Bulbus, Fritillariae Thunbergii Bulbus, Pinelliae Rhizoma in different ratios with Wu-tou decoction （2：1, 1：1, 1：2） by measuring the therapeutic effects in Wu-tou decoction of main seven alkaloids including benzoylaconitine （BA）, benzoylmesaconitine （BM）, benzoylhypaconitine （BH）, hypaconitine （HA）, fuziline （FU）, niaolin （NE） and deoxyaconitine （DA）. The permeability of aconitum alkaloids extract through a Caco-2 cell monolayer was analyzed in the absence and presence of Fritillariae Cirrhosae Bulbus, Fritillariae Thunbergii Bulbus, and Pinelliae Rhizoma, respectively. The results showed that Pinelliae Rhizoma could reduce the absorption of the alkaloids and increase the excretion of the alkaloids, which would attenuate the therapeutic effects of Wu-tou decoction. Therefore, Pinelliae Rhizoma is an incompatible herb of Wu-tou decoction because of the inhibition of the absorption of alkaloids in the intestine. And that Fritillariae Cirrhosae Bulbus and Fritillariae rhunbergii Bulbus showed the effects to improve the permeability of the alkaloids in Wu-tou decoction. These effects of these two herbs were similar, but the former was stronger than the latter, which most likely is due to the fact that the compositions of these two traditional Chinese medicines are similar. The in vitro data suggests that the compounds such as fritillary presented in alkaloids in the formula maybe improve the therapeutic function caused by the increased bioavailability of alkaloids in intestine.
文摘The metaphosphate anion, PO_3, was detected in the negative-ion chemicalionization mass spectra of 2,6,7-trioxa-1-phospbabicyclo[2.2. 2] octane-1-oxides.
基金supported by the National Natural Science Foundation of China(22479113,52101268)the Fundamental Research Funds for the Central Universities(buctrc202323)。
文摘Efficient alkaline hydrogen evolution reaction(HER)catalysts are critical for anion exchange membrane water electrolysis(AEMWE).However,the intrinsic scaling relationship between water dissociation and OH desorption fundamentally impedes designing catalysts requiring concurrent superior water dissociation and facile OH desorption.Here,we engineer a superhydrophilic Ru/Cr_(2)O_(3) heterostructured electrocatalyst through in situ confinement of Ru nanoparticles(5-10 nm)within a Cr_(2)O_(3) matrix.Acting as a Lewis acid,the Cr_(2)O_(3) component provides alternative sites for water dissociation,accelerating the Volmer step kinetics and downshifting the Ru d-band center via interfacial charge transfer,while simultaneously adsorbing OH-to form a surface-bound Lewis base that repels excess OH-from Ru sites,thereby suppressing hydroxyl over-adsorption.Concurrently,the superhydrophilic surface architecture promotes efficient hydrogen bubble release,thereby reducing mass transport resistance.As a result,the Ru/Cr_(2)O_(3) heterostructured electrocatalyst exhibits an ultralow overpotential of 36.7 mV at 10 mA cm^(-2) and a Tafel slope of 33.2 mV dec^(-1).Integrated into an AEMWE device,the electrode delivers500 mA cm^(-2) for 2000 h in 1.0 M KOH,underscoring its industrial viability(hydrogen production energy consumption per cubic meter(EW):3.94 kW h m^(-3);electricity-to-hydrogen energy conversion efficiency(η_(ETH)):89%@80℃).
