The supergiant Shuangjianzishan(SJZ) Ag-Pb-Zn deposit is in the southern segment of the Great Hinggan Range(SGHR), northeast China. Previous studies suggest the ore-forming material and fluid originated from the magma...The supergiant Shuangjianzishan(SJZ) Ag-Pb-Zn deposit is in the southern segment of the Great Hinggan Range(SGHR), northeast China. Previous studies suggest the ore-forming material and fluid originated from the magmatic system, and the mineralization age was consistent with the diagenetic age. However,the relationship between granitic magmatism and mineralization is still unclear in the SJZ. In this study, CH-O-He-Ar and in-situ S-Pb isotope analyses were conducted to determine the sources of ore-forming fluids and metals, which were combined with geochemistry data of SJZ granitoids from previous studies to constrain the relationship between the magmatism and the mineralization. The C-H-O-He-Ar-S-Pb isotopic compositions suggested the SJZ ore-forming material and fluids were derived from a magmatic source, which has mixed a small amount of mantle-derived materials. In addition, the disseminated sulfide from the syenogranite has comparable S-Pb isotopic composition with the sulfide minerals from ore veins,suggesting that the generation of the SJZ ore-forming fluids has a close relationship with the syenogranite magmatism. Combining with the geochemical characters of the syenogranite, the authors proposed that the mantle-derived fingerprint of the SJZ ore-forming fluid might be caused by the parent magma of the syenogranite, which was derived from partial melting of the juvenile lower crust, and underwent the residual melts segregated from a crystal mush in the shallow magma reservoir. The extraction of the syenogranite parent magma further concentrated the fertilized fluids, which was crucial to mineralization of the SJZ Ag-Pb-Zn deposit.展开更多
AIM: To investigate the photodynamic effect of Cd Se/Zn S quantum dots(QDs) on pancreatic cancer cells and elucidate the probable mechanisms.METHODS: The pancreatic cancer cell line SW1990 was treated with different c...AIM: To investigate the photodynamic effect of Cd Se/Zn S quantum dots(QDs) on pancreatic cancer cells and elucidate the probable mechanisms.METHODS: The pancreatic cancer cell line SW1990 was treated with different concentrations of Cd Se/Zn S QDs(0, 0.5, 1.0, 1.5, 2.0, 2.5 μmol/L), with or without illumination. The viability of SW1990 cells was tested using the Cell Counting Kit-8(CCK-8) assay. The ultrastructural changes of SW1990 cells were observed by transmission electron microscopy. Apoptosis was detected by nuclear staining and flow cytometry(FCM). Reactive oxygen species(ROS) were measured by dichlorofluorescein diacetate via fluorescence microscopy. Expression of Bax, Bcl-2 and caspase-3 was measured by real-time polymerase chain reaction(PCR) and protein immunoblotting 24 h after SW1990 cells were treated with Cd Se/Zn S QDs and illuminated.RESULTS: The CCK-8 assay results showed that both Cd Se/Zn S QDs with and without illumination suppressed SW1990 cell proliferation. Cell viability was significantly lower when illuminated or with a longer incubation time and a higher light dose. Cd Se/Zn S QDs with illumination caused ultrastructural changes in SW1990 cells, such as organelle degeneration and chromatin condensation and aggregation at the periphery of the nucleus. Fluorescence microscopy and FCM showed that Cd Se/Zn S QDs(1.5 μmol/L) with illumination increased SW1990 cell apoptosis(53.2%) and ROS generation compared with no illumination. Real-time PCR showed that expression of Bax and caspase-3 was upregulated and Bcl-2 was downregulated. Immunoblotting results were consistent with real-time PCR results. Inhibition of ROS and apoptosis both attenuated QD-photodynamictherapy-induced cell death.CONCLUSION: Cd Se/Zn S QDs can be used as a photosensitizer to inhibit SW1990 cell proliferation through ROS generation and apoptotic protein expression regulation.展开更多
BACKGROUND Whether regional lymphadenectomy(RL)should be routinely performed in patients with T1b gallbladder cancer(GBC)remains a subject of debate.AIM To investigate whether RL can improve the prognosis of patients ...BACKGROUND Whether regional lymphadenectomy(RL)should be routinely performed in patients with T1b gallbladder cancer(GBC)remains a subject of debate.AIM To investigate whether RL can improve the prognosis of patients with T1b GBC.METHODS We studied a multicenter cohort of patients with T1b GBC who underwent surgery between 2008 and 2016 at 24 hospitals in 13 provinces in China.The logrank test and Cox proportional hazards model were used to compare the overall survival(OS)of patients who underwent cholecystectomy(Ch)+RL and those who underwent Ch only.To investigate whether combined hepatectomy(Hep)improved OS in T1b patients,we studied patients who underwent Ch+RL to compare the OS of patients who underwent combined Hep and patients who did not.RESULTS Of the 121 patients(aged 61.9±10.1 years),77(63.6%)underwent Ch+RL,and 44(36.4%)underwent Ch only.Seven(9.1%)patients in the Ch+RL group had lymph node metastasis.The 5-year OS rate was significantly higher in the Ch+RL group than in the Ch group(76.3%vs 56.8%,P=0.036).Multivariate analysis showed that Ch+RL was significantly associated with improved OS(hazard ratio:0.51;95%confidence interval:0.26-0.99).Among the 77 patients who underwent Ch+RL,no survival improvement was found in patients who underwent combined Hep(5-year OS rate:79.5%for combined Hep and 76.1%for no Hep;P=0.50).CONCLUSION T1b GBC patients who underwent Ch+RL had a better prognosis than those who underwent Ch.Hep+Ch showed no improvement in prognosis in T1b GBC patients.Although recommended by both the National Comprehensive Cancer Network and Chinese Medical Association guidelines,RL was only performed in 63.6%of T1b GBC patients.Routine Ch+RL should be advised in T1b GBC.展开更多
A method is proposed for the prospecting prediction of subsurface mineral deposits based on soil geochemistry data and a deep convolutional neural network model.This method uses three techniques(window offset,scaling,...A method is proposed for the prospecting prediction of subsurface mineral deposits based on soil geochemistry data and a deep convolutional neural network model.This method uses three techniques(window offset,scaling,and rotation)to enhance the number of training data for the model.A window area is used to extract the spatial distribution characteristics of soil geochemistry and measure their correspondence with the occurrence of known subsurface deposits.Prospecting prediction is achieved by matching the characteristics of the window area of an unknown area with the relationships established in the known area.This method can efficiently predict mineral prospective areas where there are few ore deposits used for generating the training dataset,meaning that the deep-learning method can be effectively used for deposit prospecting prediction.Using soil active geochemical measurement data,this method was applied in the Daqiao area,Gansu Province,for which seven favorable gold prospecting target areas were predicted.The Daqiao orogenic gold deposit of latest Jurassic and Early Jurassic age in the southern domain has more than 105 t of gold resources at an average grade of 3-4 g/t.In 2020,the project team drilled and verified the K prediction area,and found 66 m gold mineralized bodies.The new method should be applicable to prospecting prediction using conventional geochemical data in other areas.展开更多
Objective: To study the local inflammatory stress response and pain mediator secretion after impacted wisdom tooth extraction with high-speed turbine drill combined with original luxator. Methods: Patients who receive...Objective: To study the local inflammatory stress response and pain mediator secretion after impacted wisdom tooth extraction with high-speed turbine drill combined with original luxator. Methods: Patients who received impacted wisdom tooth extraction in the First People's Hospital ofYunnan Province between March 2014 and June 2017 were selected as the research objects and randomly divided into the observation group who accepted impacted wisdom tooth extraction with high-speed turbine drill combined with original luxator and the control group who accepted impacted wisdom tooth extraction with traditional chisel. The contents of inflammatory mediators, stress mediators and pain mediators in gingival crevicular fluid were measured before surgery and 3 days after surgery. Results: Three days after surgery, PTX3, ICAM1, MPO, PGE2, PPARγ, ROS, MDA, 5-HT, CGRP, SP, Gal and ATP contents in gingival crevicular fluid of both groups were higher than those before surgery whereas GPx and T-AOC contents were significantly lower than those before surgery, and PTX3, ICAM1, MPO, PGE2, PPARγ, ROS, MDA, 5-HT, CGRP, SP, Gal and ATP contents in gingival crevicular fluid of observation group were lower than those of control group whereas GPx and T-AOC contents were significantly higher than those of control group. Conclusions: The impacted wisdom tooth extraction with high-speed turbine drill combined with original luxator can reduce the local inflammatory stress response and inhibit the secretion of pain mediators.展开更多
Directional solidification of Ti-45Al-6Nb-xW(x=0,0.4,0.8;at%) alloys was performed by Bridgeman method with the stable growth rate of 5,10,and 20 μm·s^(-1).The differential scanning calorimeter(DSC) results indi...Directional solidification of Ti-45Al-6Nb-xW(x=0,0.4,0.8;at%) alloys was performed by Bridgeman method with the stable growth rate of 5,10,and 20 μm·s^(-1).The differential scanning calorimeter(DSC) results indicate that both the eutectic temperature and the transition temperature of α(Ti_3Al) to γ(TiAl) increase with W content increasing from 0 at%to 0.8 at%.For the stable growth rate of 10 μm·s^(-1),the orientations of α_2(Ti_3Al)/γ(TiAl)lamellae change from 45°(0 at%W) to 0° and near 0°(0.4at%and 0.8 at%W) to the crystal growth direction,and the spacing of α_2/γ lamellae decreases with W content increasing from 0 at%to 0.4 at%,while it increases when W content is 0.8 at%.With the increase in growth rate from5 to 10 and 20 μm·s^(-1),the lamellar spacing of α_2/γbecomes smaller,and the lamellar thickness becomes more uniform.展开更多
In this study,the two kinds of Fe–Al coatings were fabricated by pack aluminizing on low-carbon steel at different temperatures.The corrosion behavior of the Fe–Al coatings in artificial seawater was investigated by...In this study,the two kinds of Fe–Al coatings were fabricated by pack aluminizing on low-carbon steel at different temperatures.The corrosion behavior of the Fe–Al coatings in artificial seawater was investigated by the electrochemical and weight loss techniques.Results show that the thickness of coating layer increases with increasing aluminizing temperature.The coatings exhibit high micro-hardness and good metallurgical bonding with the substrate.In comparison with the steel substrate,the corrosion current density Icorrof the Fe–Al coatings is always lower than that of substrate,about 1/38 or 1/33 after 2 h immersion,and 1/3 or 1/6 for 720 h immersion.As can be seen from the weight loss curve,the Fe–Al coatings show less loss than that of the substrate within 30-day immersion.The corrosion products formed on the surface of the coatings include oxides of Al,Mg,Fe and Ca,and pitting defect has also been found.The Fe–Al coating with higher content of Fe_2Al_5 has better corrosion resistance.展开更多
The morphology and kinetics evolution of the γ’(Ni3 Al)phase during re-dissolution are studied in Ni-15 at% Al alloy,the changes of volume fraction and average particle radius of theγ’phase were clarified with pha...The morphology and kinetics evolution of the γ’(Ni3 Al)phase during re-dissolution are studied in Ni-15 at% Al alloy,the changes of volume fraction and average particle radius of theγ’phase were clarified with phasefield simulation.During isothermal aging,the interdistance of the neighboringγ’phase affects the interface concentration gradient of Al,which dominates the growth or redissolution of the γ’phase particle.After isothermal aging at 700 K,the alloy is continuously heated to 900 K with different heating rates,the re-dissolution lag happens,meaning the coalescence coarsening of adjacent γ’phase particles still proceeds at the initial heating stage.The predissolution of γ’phase with cubic shape is re-dissolved firstly at the edges and corners,in continuous heating to 900 K or by second-order aging from 700 to 900 K.Different from continuous heating,in the second-order aging process,the connected particles with band shape are broken initially by re-dissolving.At different heating rates,the similar dynamic relationships are abstracted for the volume fraction and the heating rates,and the average particle radius and the heating rates.展开更多
The precipitation dynamics of γ’(L1-NiAl)phase and composition interfacial width between γ(fcc Ni)and γ’ phase were investigated using the phase field simulation linking with CALPHAD method.The coarsening rate an...The precipitation dynamics of γ’(L1-NiAl)phase and composition interfacial width between γ(fcc Ni)and γ’ phase were investigated using the phase field simulation linking with CALPHAD method.The coarsening rate and particle size distribution(PSD) of γ’ phase,the temporal composition interfacial width of γ/γ’ in Ni-17 at% Al alloy aged at 923,973 and 1023 K were clarified.As the aging temperature increases,the morphology of γ’ phase changes from the interconnected rectangle shape to the separated cuboidal shape.The average particle radius(<r>) of γ’ phase at coarsening stage follows <r> ∞t^(n) with the exponents n=0.21,0.23 and 0.26,respectively.The peak values of simulated PSDs at 923 K are less than the value calculated by the Lifshitz-Slyozov-Wagner(LSW) model,and the width of simulated PSD increases at later stage of precipitation.The normalized radius(r/<r>)which corresponds to the peak value of PSD moves from1.1 to 1.0 as the aging temperature increases from 923 to1023 K,and they are smaller than that of LSW model.The composition interfacial width decreases as the aging progresses and increases as the aging temperature increases.展开更多
In recent years,organic field-effect transistors(OFETs) with high performance and novel multifunctionalities have attracted considerable attention.Meanwhile,featured with reversible photoisomerization and the correspo...In recent years,organic field-effect transistors(OFETs) with high performance and novel multifunctionalities have attracted considerable attention.Meanwhile,featured with reversible photoisomerization and the corresponding variation in color,chemical/physical properties,photochromic molecules have been applied in sensors,photo-switches and memories.Incorporation of photochromic molecules to blend in the device functional layers or to modify the interfaces of OFETs is common way to build photo-transistors.In this review,we focus on the recent advantages on the study of photoresponsive transistors involving one of three typical photochromic compounds spiropyran,diarylethene and azobenzene.Three main strategies are demonstrated in detail.Firstly,photochromic molecules are doped in active layers or combined with semiconductor structure thus forming photoreversible active layers.Secondly,the modification of dielectric layer/active layer interface is mainly carried out by bilayer dielectric.Thirdly,the photo-isomerization of self-assembled monolayer(SAM) on the electrode/active layer interface can reversibly modulate the work functions and charge injection barrier,result in bifunctional OFETs.All in all,the combination of photochromic molecules and OFETs is an efficient way for the fabrication of organic photoelectric devices.Photoresponsive transistors consisted of photochromic molecules are potential candidate for real applications in the future.展开更多
Introducing photochromic molecules into the active layer of organic field-effect transistors(OFETs) is a direct way to implement a photoresponse nature in OFETs. However, active layer blended photoresponsive transisto...Introducing photochromic molecules into the active layer of organic field-effect transistors(OFETs) is a direct way to implement a photoresponse nature in OFETs. However, active layer blended photoresponsive transistors based on n-type semiconductors are challenging and rarely studied, which are crucial for multifunctional organic-based logic applications. Herein, we fabricated n-channel photoresponsive OFETs based on a tri-component active layer spin-coated from the mixed solution of an n-type semiconductor(NDI20 D-DTYM2), spiropyran and polystyrene with a weight ratio of 1:1:1. The morphology of the blended films was improved by the introduction of the polymer matrix. Photochromic spiropyran molecules dispersed in the semiconductor layer could switch between the closed-ring state and ionic open-ring state flexibly under the irradiation of different wavelengths of light, and thus change the channel conductivity reversibly and modulate the OFET characteristics. Therefore, under the irradiation of alternate UV and vis light, both the device carrier mobility and current on and off ratio successfully realized a reversible switch.展开更多
The interdiffusion interface microstructures and composition evolution of Ni-Al-Cr/Ni-Al-Cr layered alloys under different temperature gradients were studied using phase-field simulation.A precipitate-free zone forms ...The interdiffusion interface microstructures and composition evolution of Ni-Al-Cr/Ni-Al-Cr layered alloys under different temperature gradients were studied using phase-field simulation.A precipitate-free zone forms near the interface of the layered alloys,and the interface does not move with time under temperature gradients.When Cr concentrations in the alloy layers are different,Al diffuses from a low-to high-temperature region,whereas Cr from a high-to low-temperature region.The width of the precipitate-free zone changes from 0.5 to 2.5μm as the temperature gradient changes fromΔT=0.625 K·μm^(−1) to 1.250 K·μm^(−1);the width of the interdiffusion zone is also enlarged.Additionally,the temperature gradient promotes the interdiffusion of elements through the interface.In contrast,when the initial Al concentration is different in the alloy layers,an uphill diffusion of Al occurs,which is driven by the chemical potential of Al.展开更多
Record-breaking numbers of Northeast China cold vortex(NCCV)occurred during the late spring(April-May)of 2021,which provided favorable background for more severe convection weather(such as hailstorm and tornado)happen...Record-breaking numbers of Northeast China cold vortex(NCCV)occurred during the late spring(April-May)of 2021,which provided favorable background for more severe convection weather(such as hailstorm and tornado)happened and struck Jiangsu and Hubei provinces,China,causing heavy casualties and property losses.To better understand the possible causes of extremely abnormal NCCV activities,the external forcing and dynamical analysis was conducted.The results show that the extreme NCCV activity is regulated by the preceding sea surface temperature(SST)anomalies in the tropical Pacific,the snow conditions over the Tibetan Plateau,and the wave-mean flow interaction over the Eurasian continent.During the preceding autumn and winter in 2020,a moderate La Niña event occurred over the tropical Pacific,which triggered the Pacific-North America teleconnection pattern(PNA)like wave train and further dispersed the Rossby wave energy downstream along the mid-latitude westerly jet,forming a zonal wave train over the Eurasian continent.Moreover,the second minimum snow depth was recorded over the southeastern Tibetan Plateau during the boreal winter of 2020/2021,which induced a concurrent local anomalous anticyclone and a cyclone over northeast Asia in the following spring.Finally,the anomalous circulation is capable of achieving energy from the mean state through barotropic energy conversion and strengthening the downstream wave train accordingly.This study highlights the joint impacts of external forcings and internal atmospheric processes on the NCCV activity.展开更多
基金supported financially by the China Geological Survey project [DD20160123 (DD-16-049, D1522), DD20160050, DD20190370]the Fundamental Research Funds for the Central Universities (310827171122)the National Natural Science Foundation of China (Grant 41672068)。
文摘The supergiant Shuangjianzishan(SJZ) Ag-Pb-Zn deposit is in the southern segment of the Great Hinggan Range(SGHR), northeast China. Previous studies suggest the ore-forming material and fluid originated from the magmatic system, and the mineralization age was consistent with the diagenetic age. However,the relationship between granitic magmatism and mineralization is still unclear in the SJZ. In this study, CH-O-He-Ar and in-situ S-Pb isotope analyses were conducted to determine the sources of ore-forming fluids and metals, which were combined with geochemistry data of SJZ granitoids from previous studies to constrain the relationship between the magmatism and the mineralization. The C-H-O-He-Ar-S-Pb isotopic compositions suggested the SJZ ore-forming material and fluids were derived from a magmatic source, which has mixed a small amount of mantle-derived materials. In addition, the disseminated sulfide from the syenogranite has comparable S-Pb isotopic composition with the sulfide minerals from ore veins,suggesting that the generation of the SJZ ore-forming fluids has a close relationship with the syenogranite magmatism. Combining with the geochemical characters of the syenogranite, the authors proposed that the mantle-derived fingerprint of the SJZ ore-forming fluid might be caused by the parent magma of the syenogranite, which was derived from partial melting of the juvenile lower crust, and underwent the residual melts segregated from a crystal mush in the shallow magma reservoir. The extraction of the syenogranite parent magma further concentrated the fertilized fluids, which was crucial to mineralization of the SJZ Ag-Pb-Zn deposit.
基金Supported by the National Natural Science Foundation of China,No.81472844 and No.81301826Shanghai Municipal Education Commission,No.14ZZ114
文摘AIM: To investigate the photodynamic effect of Cd Se/Zn S quantum dots(QDs) on pancreatic cancer cells and elucidate the probable mechanisms.METHODS: The pancreatic cancer cell line SW1990 was treated with different concentrations of Cd Se/Zn S QDs(0, 0.5, 1.0, 1.5, 2.0, 2.5 μmol/L), with or without illumination. The viability of SW1990 cells was tested using the Cell Counting Kit-8(CCK-8) assay. The ultrastructural changes of SW1990 cells were observed by transmission electron microscopy. Apoptosis was detected by nuclear staining and flow cytometry(FCM). Reactive oxygen species(ROS) were measured by dichlorofluorescein diacetate via fluorescence microscopy. Expression of Bax, Bcl-2 and caspase-3 was measured by real-time polymerase chain reaction(PCR) and protein immunoblotting 24 h after SW1990 cells were treated with Cd Se/Zn S QDs and illuminated.RESULTS: The CCK-8 assay results showed that both Cd Se/Zn S QDs with and without illumination suppressed SW1990 cell proliferation. Cell viability was significantly lower when illuminated or with a longer incubation time and a higher light dose. Cd Se/Zn S QDs with illumination caused ultrastructural changes in SW1990 cells, such as organelle degeneration and chromatin condensation and aggregation at the periphery of the nucleus. Fluorescence microscopy and FCM showed that Cd Se/Zn S QDs(1.5 μmol/L) with illumination increased SW1990 cell apoptosis(53.2%) and ROS generation compared with no illumination. Real-time PCR showed that expression of Bax and caspase-3 was upregulated and Bcl-2 was downregulated. Immunoblotting results were consistent with real-time PCR results. Inhibition of ROS and apoptosis both attenuated QD-photodynamictherapy-induced cell death.CONCLUSION: Cd Se/Zn S QDs can be used as a photosensitizer to inhibit SW1990 cell proliferation through ROS generation and apoptotic protein expression regulation.
基金National Natural Science Foundation of China(General Program),No.31620103910National Natural Science Foundation of China(Key Program),No.81874181+3 种基金National Health Commission of China,No.2019ZX09301158Shanghai Municipal Commission of Economy and Informatization,No.2019RGZN01096Shanghai Shenkang Hospital Development Center,No.12018107and Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,No.19XHCR13D.
文摘BACKGROUND Whether regional lymphadenectomy(RL)should be routinely performed in patients with T1b gallbladder cancer(GBC)remains a subject of debate.AIM To investigate whether RL can improve the prognosis of patients with T1b GBC.METHODS We studied a multicenter cohort of patients with T1b GBC who underwent surgery between 2008 and 2016 at 24 hospitals in 13 provinces in China.The logrank test and Cox proportional hazards model were used to compare the overall survival(OS)of patients who underwent cholecystectomy(Ch)+RL and those who underwent Ch only.To investigate whether combined hepatectomy(Hep)improved OS in T1b patients,we studied patients who underwent Ch+RL to compare the OS of patients who underwent combined Hep and patients who did not.RESULTS Of the 121 patients(aged 61.9±10.1 years),77(63.6%)underwent Ch+RL,and 44(36.4%)underwent Ch only.Seven(9.1%)patients in the Ch+RL group had lymph node metastasis.The 5-year OS rate was significantly higher in the Ch+RL group than in the Ch group(76.3%vs 56.8%,P=0.036).Multivariate analysis showed that Ch+RL was significantly associated with improved OS(hazard ratio:0.51;95%confidence interval:0.26-0.99).Among the 77 patients who underwent Ch+RL,no survival improvement was found in patients who underwent combined Hep(5-year OS rate:79.5%for combined Hep and 76.1%for no Hep;P=0.50).CONCLUSION T1b GBC patients who underwent Ch+RL had a better prognosis than those who underwent Ch.Hep+Ch showed no improvement in prognosis in T1b GBC patients.Although recommended by both the National Comprehensive Cancer Network and Chinese Medical Association guidelines,RL was only performed in 63.6%of T1b GBC patients.Routine Ch+RL should be advised in T1b GBC.
基金funded by a pilot project entitled“Deep Geological Survey of Benxi-Linjiang Area”(1212011220247)of the 3D Geological Mapping and Deep Geological Survey of China Geological Survey。
文摘A method is proposed for the prospecting prediction of subsurface mineral deposits based on soil geochemistry data and a deep convolutional neural network model.This method uses three techniques(window offset,scaling,and rotation)to enhance the number of training data for the model.A window area is used to extract the spatial distribution characteristics of soil geochemistry and measure their correspondence with the occurrence of known subsurface deposits.Prospecting prediction is achieved by matching the characteristics of the window area of an unknown area with the relationships established in the known area.This method can efficiently predict mineral prospective areas where there are few ore deposits used for generating the training dataset,meaning that the deep-learning method can be effectively used for deposit prospecting prediction.Using soil active geochemical measurement data,this method was applied in the Daqiao area,Gansu Province,for which seven favorable gold prospecting target areas were predicted.The Daqiao orogenic gold deposit of latest Jurassic and Early Jurassic age in the southern domain has more than 105 t of gold resources at an average grade of 3-4 g/t.In 2020,the project team drilled and verified the K prediction area,and found 66 m gold mineralized bodies.The new method should be applicable to prospecting prediction using conventional geochemical data in other areas.
文摘Objective: To study the local inflammatory stress response and pain mediator secretion after impacted wisdom tooth extraction with high-speed turbine drill combined with original luxator. Methods: Patients who received impacted wisdom tooth extraction in the First People's Hospital ofYunnan Province between March 2014 and June 2017 were selected as the research objects and randomly divided into the observation group who accepted impacted wisdom tooth extraction with high-speed turbine drill combined with original luxator and the control group who accepted impacted wisdom tooth extraction with traditional chisel. The contents of inflammatory mediators, stress mediators and pain mediators in gingival crevicular fluid were measured before surgery and 3 days after surgery. Results: Three days after surgery, PTX3, ICAM1, MPO, PGE2, PPARγ, ROS, MDA, 5-HT, CGRP, SP, Gal and ATP contents in gingival crevicular fluid of both groups were higher than those before surgery whereas GPx and T-AOC contents were significantly lower than those before surgery, and PTX3, ICAM1, MPO, PGE2, PPARγ, ROS, MDA, 5-HT, CGRP, SP, Gal and ATP contents in gingival crevicular fluid of observation group were lower than those of control group whereas GPx and T-AOC contents were significantly higher than those of control group. Conclusions: The impacted wisdom tooth extraction with high-speed turbine drill combined with original luxator can reduce the local inflammatory stress response and inhibit the secretion of pain mediators.
基金financially supported by the National Basic Research Program of China(No.2011CB605504)the National Natural Science Foundation of China(No.51571122)the Fundamental Research Funds for the Central Universities(No.30920130121012)
文摘Directional solidification of Ti-45Al-6Nb-xW(x=0,0.4,0.8;at%) alloys was performed by Bridgeman method with the stable growth rate of 5,10,and 20 μm·s^(-1).The differential scanning calorimeter(DSC) results indicate that both the eutectic temperature and the transition temperature of α(Ti_3Al) to γ(TiAl) increase with W content increasing from 0 at%to 0.8 at%.For the stable growth rate of 10 μm·s^(-1),the orientations of α_2(Ti_3Al)/γ(TiAl)lamellae change from 45°(0 at%W) to 0° and near 0°(0.4at%and 0.8 at%W) to the crystal growth direction,and the spacing of α_2/γ lamellae decreases with W content increasing from 0 at%to 0.4 at%,while it increases when W content is 0.8 at%.With the increase in growth rate from5 to 10 and 20 μm·s^(-1),the lamellar spacing of α_2/γbecomes smaller,and the lamellar thickness becomes more uniform.
基金supported by the Foundation of Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology (No. ASMA 201403)Cooperative Innovation Fund of Jiangsu Province (No. BY 2014004-09)
文摘In this study,the two kinds of Fe–Al coatings were fabricated by pack aluminizing on low-carbon steel at different temperatures.The corrosion behavior of the Fe–Al coatings in artificial seawater was investigated by the electrochemical and weight loss techniques.Results show that the thickness of coating layer increases with increasing aluminizing temperature.The coatings exhibit high micro-hardness and good metallurgical bonding with the substrate.In comparison with the steel substrate,the corrosion current density Icorrof the Fe–Al coatings is always lower than that of substrate,about 1/38 or 1/33 after 2 h immersion,and 1/3 or 1/6 for 720 h immersion.As can be seen from the weight loss curve,the Fe–Al coatings show less loss than that of the substrate within 30-day immersion.The corrosion products formed on the surface of the coatings include oxides of Al,Mg,Fe and Ca,and pitting defect has also been found.The Fe–Al coating with higher content of Fe_2Al_5 has better corrosion resistance.
基金supported by the National Natural Science Foundation of China(No.51571122)the Fundamental Research Funds for the Central Universities(No 30916015107)。
文摘The morphology and kinetics evolution of the γ’(Ni3 Al)phase during re-dissolution are studied in Ni-15 at% Al alloy,the changes of volume fraction and average particle radius of theγ’phase were clarified with phasefield simulation.During isothermal aging,the interdistance of the neighboringγ’phase affects the interface concentration gradient of Al,which dominates the growth or redissolution of the γ’phase particle.After isothermal aging at 700 K,the alloy is continuously heated to 900 K with different heating rates,the re-dissolution lag happens,meaning the coalescence coarsening of adjacent γ’phase particles still proceeds at the initial heating stage.The predissolution of γ’phase with cubic shape is re-dissolved firstly at the edges and corners,in continuous heating to 900 K or by second-order aging from 700 to 900 K.Different from continuous heating,in the second-order aging process,the connected particles with band shape are broken initially by re-dissolving.At different heating rates,the similar dynamic relationships are abstracted for the volume fraction and the heating rates,and the average particle radius and the heating rates.
基金financially supported by the National Natural Science Foundation of China (No.51571122)the Fundamental Research Funds for the Central Universities (No. 30920130121012)the Graduate Innovation Project of Jiangsu Province (No.SJLX_0157)。
文摘The precipitation dynamics of γ’(L1-NiAl)phase and composition interfacial width between γ(fcc Ni)and γ’ phase were investigated using the phase field simulation linking with CALPHAD method.The coarsening rate and particle size distribution(PSD) of γ’ phase,the temporal composition interfacial width of γ/γ’ in Ni-17 at% Al alloy aged at 923,973 and 1023 K were clarified.As the aging temperature increases,the morphology of γ’ phase changes from the interconnected rectangle shape to the separated cuboidal shape.The average particle radius(<r>) of γ’ phase at coarsening stage follows <r> ∞t^(n) with the exponents n=0.21,0.23 and 0.26,respectively.The peak values of simulated PSDs at 923 K are less than the value calculated by the Lifshitz-Slyozov-Wagner(LSW) model,and the width of simulated PSD increases at later stage of precipitation.The normalized radius(r/<r>)which corresponds to the peak value of PSD moves from1.1 to 1.0 as the aging temperature increases from 923 to1023 K,and they are smaller than that of LSW model.The composition interfacial width decreases as the aging progresses and increases as the aging temperature increases.
基金supported financially by the National Natural Science Foundation of China(Nos.21302212 and 21522209)the "Strategic Priority Research Program"(No.XDB12010100)
文摘In recent years,organic field-effect transistors(OFETs) with high performance and novel multifunctionalities have attracted considerable attention.Meanwhile,featured with reversible photoisomerization and the corresponding variation in color,chemical/physical properties,photochromic molecules have been applied in sensors,photo-switches and memories.Incorporation of photochromic molecules to blend in the device functional layers or to modify the interfaces of OFETs is common way to build photo-transistors.In this review,we focus on the recent advantages on the study of photoresponsive transistors involving one of three typical photochromic compounds spiropyran,diarylethene and azobenzene.Three main strategies are demonstrated in detail.Firstly,photochromic molecules are doped in active layers or combined with semiconductor structure thus forming photoreversible active layers.Secondly,the modification of dielectric layer/active layer interface is mainly carried out by bilayer dielectric.Thirdly,the photo-isomerization of self-assembled monolayer(SAM) on the electrode/active layer interface can reversibly modulate the work functions and charge injection barrier,result in bifunctional OFETs.All in all,the combination of photochromic molecules and OFETs is an efficient way for the fabrication of organic photoelectric devices.Photoresponsive transistors consisted of photochromic molecules are potential candidate for real applications in the future.
基金the National Natural Science Foundation of China (Nos. 21302212 and 21522209)the "Strategic Priority Research Program"(No. XDB12010100) for funding this work
文摘Introducing photochromic molecules into the active layer of organic field-effect transistors(OFETs) is a direct way to implement a photoresponse nature in OFETs. However, active layer blended photoresponsive transistors based on n-type semiconductors are challenging and rarely studied, which are crucial for multifunctional organic-based logic applications. Herein, we fabricated n-channel photoresponsive OFETs based on a tri-component active layer spin-coated from the mixed solution of an n-type semiconductor(NDI20 D-DTYM2), spiropyran and polystyrene with a weight ratio of 1:1:1. The morphology of the blended films was improved by the introduction of the polymer matrix. Photochromic spiropyran molecules dispersed in the semiconductor layer could switch between the closed-ring state and ionic open-ring state flexibly under the irradiation of different wavelengths of light, and thus change the channel conductivity reversibly and modulate the OFET characteristics. Therefore, under the irradiation of alternate UV and vis light, both the device carrier mobility and current on and off ratio successfully realized a reversible switch.
基金financially supported by the National Natural Science Foundation of China(No.51571122)the Fundamental Research Funds for the Central Universities(No.30921013107)。
文摘The interdiffusion interface microstructures and composition evolution of Ni-Al-Cr/Ni-Al-Cr layered alloys under different temperature gradients were studied using phase-field simulation.A precipitate-free zone forms near the interface of the layered alloys,and the interface does not move with time under temperature gradients.When Cr concentrations in the alloy layers are different,Al diffuses from a low-to high-temperature region,whereas Cr from a high-to low-temperature region.The width of the precipitate-free zone changes from 0.5 to 2.5μm as the temperature gradient changes fromΔT=0.625 K·μm^(−1) to 1.250 K·μm^(−1);the width of the interdiffusion zone is also enlarged.Additionally,the temperature gradient promotes the interdiffusion of elements through the interface.In contrast,when the initial Al concentration is different in the alloy layers,an uphill diffusion of Al occurs,which is driven by the chemical potential of Al.
基金National Natural Science Foundation of China(41905067,42175052)National Key Research and Development Program(2021YFA0718000)+1 种基金Innovative Development Special Project of China Meteorological Administration(CXFZ2021Z011,CXFZ2021Z010 and CXFZ2022J039)science funding from Beijing Meteorological Service(BMBKJ202003005).
文摘Record-breaking numbers of Northeast China cold vortex(NCCV)occurred during the late spring(April-May)of 2021,which provided favorable background for more severe convection weather(such as hailstorm and tornado)happened and struck Jiangsu and Hubei provinces,China,causing heavy casualties and property losses.To better understand the possible causes of extremely abnormal NCCV activities,the external forcing and dynamical analysis was conducted.The results show that the extreme NCCV activity is regulated by the preceding sea surface temperature(SST)anomalies in the tropical Pacific,the snow conditions over the Tibetan Plateau,and the wave-mean flow interaction over the Eurasian continent.During the preceding autumn and winter in 2020,a moderate La Niña event occurred over the tropical Pacific,which triggered the Pacific-North America teleconnection pattern(PNA)like wave train and further dispersed the Rossby wave energy downstream along the mid-latitude westerly jet,forming a zonal wave train over the Eurasian continent.Moreover,the second minimum snow depth was recorded over the southeastern Tibetan Plateau during the boreal winter of 2020/2021,which induced a concurrent local anomalous anticyclone and a cyclone over northeast Asia in the following spring.Finally,the anomalous circulation is capable of achieving energy from the mean state through barotropic energy conversion and strengthening the downstream wave train accordingly.This study highlights the joint impacts of external forcings and internal atmospheric processes on the NCCV activity.
