Theranostics is a concept that integrated imaging and therapy. As an emerging field, it embraces multiple techniques to arrive at an individualized treatment purpose. Indocyanine green(ICG) is a near infrared dye that...Theranostics is a concept that integrated imaging and therapy. As an emerging field, it embraces multiple techniques to arrive at an individualized treatment purpose. Indocyanine green(ICG) is a near infrared dye that has been approved by Food and Drug Administration(FDA) in USA for the use in indicator-dilution studies in humans. ICG nanoparticles(NPs) have attracted much attention for its potential applications in cancer theranostics. This review focuses on the preparation, application of ICG NPs for in vivo imaging(fluorescent imaging and photoacoustic imaging) and therapeutics(photothermal therapy, photodynamic therapy and photoacoustic therapy), and future directions based on recent developments in these areas. It is hoped that this review might provide new impetus to understand ICG NPs for cancer theranostics.展开更多
In this study,low-rank coal-water slurry(LCWS)was prepared using polyoxyethylene dodecylphenol ether(PDPE)and polyoxyethylene lauryl ether(PLE),respectively.A combination of experiments and simulations was used to inv...In this study,low-rank coal-water slurry(LCWS)was prepared using polyoxyethylene dodecylphenol ether(PDPE)and polyoxyethylene lauryl ether(PLE),respectively.A combination of experiments and simulations was used to investigate the pulping properties and microscopic mechanism of the LCWS samples prepared using the two agents,so as to explore the influence of benzene ring on the performance of dispersant.The results of the LCWS preparation experiments revealed that the pulp-forming performance of PDPE exceeded that of PLE.When LCWS concentration is 62%,64%,and 66%,the apparent viscosity corresponding to PDPE is 247.80,504.17,and 653.10 mPa·s,and the apparent viscosity corresponding to PLE is 548.10,1470.61,and 1549.98 mPa·s,respectively.The C_(1000)(When the apparent viscosity is 1000 mPa·s,the corresponding concentration of LCWS is defined as C_(1000))values of PDPE and PLE are 67.60%and 62.95%,respectively.In addition to the van der Waals forces and hydrogen bonds between the PDPE and/or PLE molecules and coal,the benzene rings of PDPE presentπ-πstacking effect with the aromatic rings of coal.That could facilitate and strengthen the adsorption of PDPE on coal,which would be conducive to further improving the dispersion of coal particles.The two dispersants have no significant difference in effect on the pyrolysis of LCWS.The simulation results indicated that the times for PDPE and PLE molecules to reach flat adsorption state on coal are approximately 290 and 565 ps,respectively.The self-diffusion coefficient(D)of the PDPE and PLE on coal is 3.16 x 10^(-6)and6.57×10^(-6)m~2/s,respectively,and their interaction energies with coal are 785.71 and 648.60 kcal/mol,respectively.The results of the simulation calculations demonstrated that PDPE adsorbed on coal easier than PLE,and its binding is more stable than that of PLE owing to theπ-πstacking effect,which is conducive to uniform dispersion of coal in solution.The simulation results confirmed the experimental results.展开更多
Developing efficient and highly selective catalyst to promote hydrogen generation from hydrous hydrazine(N_(2)H_(4)·H_(2)O) and hydrazine borane(N_(2)H_(4)BH_(3))remains a challenging issue for fuel cell-based hy...Developing efficient and highly selective catalyst to promote hydrogen generation from hydrous hydrazine(N_(2)H_(4)·H_(2)O) and hydrazine borane(N_(2)H_(4)BH_(3))remains a challenging issue for fuel cell-based hydrogen economy.In this work,ultrafine and well-dispersed bimetallic NiPt nanoparticles(3.4 nm) were successfully immobilized on Y_(2)O_(3)-functionalized graphene(Y_(2)O_(3)/rGO) without any surfactant by a simple liquid impregnation approach.It is firstly found that integration of graphene and Y_(2)O_(3) not only can facilitate the formation of ultrafine NiPt nanoparticles(NPs),but also can effectively modulate the electronic structure of NiPt NPs,thereby boosting the catalytic performance.Compared with NiPt/Y_(2)O_(3) and NiPt/rGO,the NiPt/Y_(2)O_(3)/rGO nanocomposites(NCs) show remarkable enhanced catalytic efficiency for hydrogen production from N_(2)H_(4)-H_(2)O.In particular,the optimized Ni_(0.6)Pt_(0.4/)Y_(2)O_(3)/rGO NCs display the best catalytic efficiency and 100% H_(2) selectivity for N_(2)H_(4)-H_(2)O dehydrogenation,providing a turnover frequency(TOF) of2182 h^(-1) at 323 K,which is among the highest values ever reported.Moreover,the Ni_(0.6)Pt_(0.4)/Y_(2)O_(3)/rGO NCs also exhibit an excellent catalytic performance(TOF=3191 h^(-1)) and 100% H_(2) selectively for N_(2)H_(4)BH_(3)dehydrogenation at 323 K.The outstanding catalytic results obtained provide more possibilities for the potential applications of N_(2)H_(4)·H_(2)O and N_(2)H_(4)BH_(3) as promising chemical hydrogen storage materials.展开更多
A minitype reference radiation(MRR) with dimensions of only 1 m × 1 m × 1 m has been developed for the in situ calibration of photon dosimeters.The present work conducts a feasibility study on determining th...A minitype reference radiation(MRR) with dimensions of only 1 m × 1 m × 1 m has been developed for the in situ calibration of photon dosimeters.The present work conducts a feasibility study on determining the conventional true value of gamma-ray air kerma at the point of test in the MRR.Owing to its smaller dimensions,the scattered gamma-rays in the MRR are expected to induce a non-negligible interference with the radiation field compared with conditions in the standard reference radiation stipulated by ISO4037-1 or GB/T12162.1.A gamma-ray spectrometer was employed to obtain the spectra of scattered gamma-rays within the MRR,and the feature components of the spectra were extracted by principal component analysis to characterize the interference of a dosimeter probe in the radiation field.A prediction model of the CAK at the point of test was built by least squares support vector machine based on the feature component data obtained from nine sample dosimeters under five different dose rates.The mean prediction error of the CAK prediction model was within ±4.5%,and the maximum prediction error was about ±10%.展开更多
In this work,monodisperseβ-NaLuF_(4):Yb,Er microcrystals with intense upconversion emission were synthesized via a modified hydrothermal method.With the increase of reactant concentration,their production yield is in...In this work,monodisperseβ-NaLuF_(4):Yb,Er microcrystals with intense upconversion emission were synthesized via a modified hydrothermal method.With the increase of reactant concentration,their production yield is increased obviously,and the upconversion emission intensity inβ-NaLuF_(4):Yb,Er microcrystals is also enhanced significantly.The luminescence enhancement should be attributed to minimal internal OH defects,validated by a combination of analytical X-ray diffraction(XRD),energy dispersive spectrum(EDS),and Eu^(3+)structural probe measurements.We also reveal that high Na^(+):RE~(3+)ratio in theβ-NaLuF_(4):Yb,Er microcrystals prepared under Na^(~)+-rich reaction will arouse the increased repulsive energy ofβ-NaLuF_(4)microcrystals between F^(~)-and OH^(~)-anions and then facilitate the substitution of large OH^(-)ions by small F^(~)-ions under F^(~)--rich reaction conditions.Minimal OH^(-)concentrations can limit nonradiative relaxation and promote excitation energy harvesting for high upconversion efficiency.The presented results not only offer a facile method for the simultaneous production yield and luminescence intensity increase ofβ-NaREF_(4)microcrystals,but also uncover a better insight into the upconversion emission alterations,which is favorable to broaden their practical applications.展开更多
Objective Antipsychotics,in particular olanzapine,are first-line medications for schizophrenia.The prefrontal cortex(PFC)is an important region for antipsychotics’therapeutic effects.The PFC inflammatory and immune p...Objective Antipsychotics,in particular olanzapine,are first-line medications for schizophrenia.The prefrontal cortex(PFC)is an important region for antipsychotics’therapeutic effects.The PFC inflammatory and immune pathways are associated with schizophrenia pathogenesis.However,the effect of antipsychotics on the inflammatory and immune pathways in the PFC remains unclear.We aimed to examined the time-dependent effect of olanzapine on inflammatory and immune markers in the PFC of rats.Since the inflammatory and immune pathways are related to endoplasmic reticulum(ER)stress,we further investigated whether or not olanzapine-induced inflammation and immune responses were related to ER stress.Methods Expression of pro-inflammatory markers including IkappaB kinaseβ(IKKβ),nuclear factor kappa B(NFκB),tumor necrosis factorα(TNF-α),interleukin-6(IL-6)and IL-1β,and immune-related proteins including inducible nitric oxide synthase(iNOS),toll-like receptor 2(TLR2)and cluster of differentiation 14(CD14)were examined by Western blotting.Results Olanzapine treatments for 1,8 and 36 days significantly activated the inflammatory IKKβ/NFκB signaling,and increased the expression of TNF-α,IL-6,IL-1βand immune-related proteins such as iNOS,TLR4 and CD14.Olanzapine treatment for 1 day,8 and 36 days also induced ER stress in the PFC.Co-treatment with an ER stress inhibitor,4-phenylbutyrate,inhibited olanzapine-induced inflammation and the immune response in the PFC.Conclusion These results suggested olanzapine exposure could be a factor that induces central inflammation and immunological abnormities in schizophrenia subjects.Olanzapine induces PFC inflammation and immune response,possibly via activating ER stress signaling.展开更多
High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it...High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment swarm.To address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography.Firstly,background difference algorithm is utilized to extract the center and area of each fragment in the image sequence.Subsequently,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment swarm.To reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial fitting.Finally,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.展开更多
Tungsten telluride thin films were successfully prepared on monocrystal sapphire substrates by using atomic layer de-position and chemical vapor deposition technology,and the effects of different tellurization tempera...Tungsten telluride thin films were successfully prepared on monocrystal sapphire substrates by using atomic layer de-position and chemical vapor deposition technology,and the effects of different tellurization temperatures on the properties of tungsten telluride films were investigated.The growth rate,crystal structure and composition of the film samples were character-ized and analyzed by using scanning electron microscope,Raman spectroscopy and X-ray photoelectron spectroscopy.The res-ults showed that tungsten telluride thin films with good crystal orientation in(001)were obtained at telluride temperature of 550℃.When the telluride temperature reached 570℃,the tungsten telluride began to decompose and unsaturated mag-netoresistance was found.展开更多
某大水型金属矿山帷幕注浆工程中应用的黏土-水泥浆液水化反应后的pH值高达13,表现为强碱性,对地下水及地表水构成了潜在污染风险。为探究低碱性外加剂对该矿山水害防治帷幕注浆工程中黏土-水泥浆液性能的调控机制,采用正交试验设计,系...某大水型金属矿山帷幕注浆工程中应用的黏土-水泥浆液水化反应后的pH值高达13,表现为强碱性,对地下水及地表水构成了潜在污染风险。为探究低碱性外加剂对该矿山水害防治帷幕注浆工程中黏土-水泥浆液性能的调控机制,采用正交试验设计,系统分析了不同配比条件下浆液的流变特性,包括流动性、泵送性能、凝结时间及pH值的变化规律。通过分别引入磷石膏、粉煤灰及降碱外加剂(substance of Jin Pin,SJP),探讨不同材料在降低浆液碱性方面的有效性。试验结果显示:磷石膏能够将浆液pH值有效降低至11,同时延长凝结时间;粉煤灰虽在降低浆液碱度方面效果有限,却改善了浆液的泵送性能并缩短了泵送期限;SJP外掺剂在降低p H值和延长泵送期方面表现突出,当掺量由2.5%增加至3.5%时,浆液pH值显著降低至8。基于试验数据,优化了SJP外掺剂-粉质黏土-磷石膏-水泥配方,并通过正交试验确定了最优配比:复合酸式盐0.5%、硫铝酸盐1.5%、磷石膏10.0%、黏土50.0%。该优化配方制备的浆液p H值降低至10,流动度保持在18~23 cm,泵送期延长至100~220 min,充分满足工程应用需求。研究结果可为帷幕注浆工程中通过控制浆液碱性减少环境污染提供了科学依据。展开更多
基金support for this research from the National Natural Science Foundation of China (Grant No. 81071249, 81171446 and 20905050)Guangdong Innovation Team of Low-cost Healthcare, Science and Technology Key Project of Guangdong (2009A030301010) and Shenzhen (CXB201005250029A, JC201005270326A, JC201005260247A, JC201104220242A)
文摘Theranostics is a concept that integrated imaging and therapy. As an emerging field, it embraces multiple techniques to arrive at an individualized treatment purpose. Indocyanine green(ICG) is a near infrared dye that has been approved by Food and Drug Administration(FDA) in USA for the use in indicator-dilution studies in humans. ICG nanoparticles(NPs) have attracted much attention for its potential applications in cancer theranostics. This review focuses on the preparation, application of ICG NPs for in vivo imaging(fluorescent imaging and photoacoustic imaging) and therapeutics(photothermal therapy, photodynamic therapy and photoacoustic therapy), and future directions based on recent developments in these areas. It is hoped that this review might provide new impetus to understand ICG NPs for cancer theranostics.
基金supported by National Natural Science Foundation of China(Nos.51904174 and 52074175)Postdoctoral Science Foundation of China(No.2019M662403)+3 种基金Young Science and Technology Innovation Program of Shandong Province(No.2020KJD001)Key Research and Development Project of Shandong(No.2019GGX103035)SDUST Research Fund(No.2018TDJH101)Project of Shandong Province Higher Educational Young Innovative Talent Introduction and Cultivation Team。
文摘In this study,low-rank coal-water slurry(LCWS)was prepared using polyoxyethylene dodecylphenol ether(PDPE)and polyoxyethylene lauryl ether(PLE),respectively.A combination of experiments and simulations was used to investigate the pulping properties and microscopic mechanism of the LCWS samples prepared using the two agents,so as to explore the influence of benzene ring on the performance of dispersant.The results of the LCWS preparation experiments revealed that the pulp-forming performance of PDPE exceeded that of PLE.When LCWS concentration is 62%,64%,and 66%,the apparent viscosity corresponding to PDPE is 247.80,504.17,and 653.10 mPa·s,and the apparent viscosity corresponding to PLE is 548.10,1470.61,and 1549.98 mPa·s,respectively.The C_(1000)(When the apparent viscosity is 1000 mPa·s,the corresponding concentration of LCWS is defined as C_(1000))values of PDPE and PLE are 67.60%and 62.95%,respectively.In addition to the van der Waals forces and hydrogen bonds between the PDPE and/or PLE molecules and coal,the benzene rings of PDPE presentπ-πstacking effect with the aromatic rings of coal.That could facilitate and strengthen the adsorption of PDPE on coal,which would be conducive to further improving the dispersion of coal particles.The two dispersants have no significant difference in effect on the pyrolysis of LCWS.The simulation results indicated that the times for PDPE and PLE molecules to reach flat adsorption state on coal are approximately 290 and 565 ps,respectively.The self-diffusion coefficient(D)of the PDPE and PLE on coal is 3.16 x 10^(-6)and6.57×10^(-6)m~2/s,respectively,and their interaction energies with coal are 785.71 and 648.60 kcal/mol,respectively.The results of the simulation calculations demonstrated that PDPE adsorbed on coal easier than PLE,and its binding is more stable than that of PLE owing to theπ-πstacking effect,which is conducive to uniform dispersion of coal in solution.The simulation results confirmed the experimental results.
基金financially supported by the National Natural Science Foundation of China (Nos. 22162013 and 22162014)Natural Science Foundation of Jiangxi Province (No. 20212ACB204009)+2 种基金the Program of the Academic and Technical Leaders of Major Disciplines of Jiangxi Province (No. 20212BCJL23059)the Thousand Talents Plan of Jiangxi Provincethe Open Project Program of State-Province Joint Engineering Laboratory of Zeolite Membrane Materials of China (No. SPJELZMM-202210)。
文摘Developing efficient and highly selective catalyst to promote hydrogen generation from hydrous hydrazine(N_(2)H_(4)·H_(2)O) and hydrazine borane(N_(2)H_(4)BH_(3))remains a challenging issue for fuel cell-based hydrogen economy.In this work,ultrafine and well-dispersed bimetallic NiPt nanoparticles(3.4 nm) were successfully immobilized on Y_(2)O_(3)-functionalized graphene(Y_(2)O_(3)/rGO) without any surfactant by a simple liquid impregnation approach.It is firstly found that integration of graphene and Y_(2)O_(3) not only can facilitate the formation of ultrafine NiPt nanoparticles(NPs),but also can effectively modulate the electronic structure of NiPt NPs,thereby boosting the catalytic performance.Compared with NiPt/Y_(2)O_(3) and NiPt/rGO,the NiPt/Y_(2)O_(3)/rGO nanocomposites(NCs) show remarkable enhanced catalytic efficiency for hydrogen production from N_(2)H_(4)-H_(2)O.In particular,the optimized Ni_(0.6)Pt_(0.4/)Y_(2)O_(3)/rGO NCs display the best catalytic efficiency and 100% H_(2) selectivity for N_(2)H_(4)-H_(2)O dehydrogenation,providing a turnover frequency(TOF) of2182 h^(-1) at 323 K,which is among the highest values ever reported.Moreover,the Ni_(0.6)Pt_(0.4)/Y_(2)O_(3)/rGO NCs also exhibit an excellent catalytic performance(TOF=3191 h^(-1)) and 100% H_(2) selectively for N_(2)H_(4)BH_(3)dehydrogenation at 323 K.The outstanding catalytic results obtained provide more possibilities for the potential applications of N_(2)H_(4)·H_(2)O and N_(2)H_(4)BH_(3) as promising chemical hydrogen storage materials.
文摘A minitype reference radiation(MRR) with dimensions of only 1 m × 1 m × 1 m has been developed for the in situ calibration of photon dosimeters.The present work conducts a feasibility study on determining the conventional true value of gamma-ray air kerma at the point of test in the MRR.Owing to its smaller dimensions,the scattered gamma-rays in the MRR are expected to induce a non-negligible interference with the radiation field compared with conditions in the standard reference radiation stipulated by ISO4037-1 or GB/T12162.1.A gamma-ray spectrometer was employed to obtain the spectra of scattered gamma-rays within the MRR,and the feature components of the spectra were extracted by principal component analysis to characterize the interference of a dosimeter probe in the radiation field.A prediction model of the CAK at the point of test was built by least squares support vector machine based on the feature component data obtained from nine sample dosimeters under five different dose rates.The mean prediction error of the CAK prediction model was within ±4.5%,and the maximum prediction error was about ±10%.
基金Project supported by the National Natural Science Foundation of China(11504317,51503177)the International Partnership Program of Chinese Academy of Sciences(121522KYSB20190022)。
文摘In this work,monodisperseβ-NaLuF_(4):Yb,Er microcrystals with intense upconversion emission were synthesized via a modified hydrothermal method.With the increase of reactant concentration,their production yield is increased obviously,and the upconversion emission intensity inβ-NaLuF_(4):Yb,Er microcrystals is also enhanced significantly.The luminescence enhancement should be attributed to minimal internal OH defects,validated by a combination of analytical X-ray diffraction(XRD),energy dispersive spectrum(EDS),and Eu^(3+)structural probe measurements.We also reveal that high Na^(+):RE~(3+)ratio in theβ-NaLuF_(4):Yb,Er microcrystals prepared under Na^(~)+-rich reaction will arouse the increased repulsive energy ofβ-NaLuF_(4)microcrystals between F^(~)-and OH^(~)-anions and then facilitate the substitution of large OH^(-)ions by small F^(~)-ions under F^(~)--rich reaction conditions.Minimal OH^(-)concentrations can limit nonradiative relaxation and promote excitation energy harvesting for high upconversion efficiency.The presented results not only offer a facile method for the simultaneous production yield and luminescence intensity increase ofβ-NaREF_(4)microcrystals,but also uncover a better insight into the upconversion emission alterations,which is favorable to broaden their practical applications.
基金supported by grants from the National Natural Science Foundation of China(No.81803515)and Natural Science Foundation of Hubei Province(No.2018CFB342).
文摘Objective Antipsychotics,in particular olanzapine,are first-line medications for schizophrenia.The prefrontal cortex(PFC)is an important region for antipsychotics’therapeutic effects.The PFC inflammatory and immune pathways are associated with schizophrenia pathogenesis.However,the effect of antipsychotics on the inflammatory and immune pathways in the PFC remains unclear.We aimed to examined the time-dependent effect of olanzapine on inflammatory and immune markers in the PFC of rats.Since the inflammatory and immune pathways are related to endoplasmic reticulum(ER)stress,we further investigated whether or not olanzapine-induced inflammation and immune responses were related to ER stress.Methods Expression of pro-inflammatory markers including IkappaB kinaseβ(IKKβ),nuclear factor kappa B(NFκB),tumor necrosis factorα(TNF-α),interleukin-6(IL-6)and IL-1β,and immune-related proteins including inducible nitric oxide synthase(iNOS),toll-like receptor 2(TLR2)and cluster of differentiation 14(CD14)were examined by Western blotting.Results Olanzapine treatments for 1,8 and 36 days significantly activated the inflammatory IKKβ/NFκB signaling,and increased the expression of TNF-α,IL-6,IL-1βand immune-related proteins such as iNOS,TLR4 and CD14.Olanzapine treatment for 1 day,8 and 36 days also induced ER stress in the PFC.Co-treatment with an ER stress inhibitor,4-phenylbutyrate,inhibited olanzapine-induced inflammation and the immune response in the PFC.Conclusion These results suggested olanzapine exposure could be a factor that induces central inflammation and immunological abnormities in schizophrenia subjects.Olanzapine induces PFC inflammation and immune response,possibly via activating ER stress signaling.
基金Key Basic Research Project of Strengthening the Foundations Plan of China (Grant No.2019-JCJQ-ZD-360-12)National Defense Basic Scientific Research Program of China (Grant No.JCKY2021208B011)to provide fund for conducting experiments。
文摘High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment swarm.To address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography.Firstly,background difference algorithm is utilized to extract the center and area of each fragment in the image sequence.Subsequently,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment swarm.To reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial fitting.Finally,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.
基金supported by the National Key Research and Development Program of China(No.2018YFA0704804)Chinese Academy of Sciences Research Instruments and Equipment Development Project(No.ZDKYYQ20220001)。
文摘Tungsten telluride thin films were successfully prepared on monocrystal sapphire substrates by using atomic layer de-position and chemical vapor deposition technology,and the effects of different tellurization temperatures on the properties of tungsten telluride films were investigated.The growth rate,crystal structure and composition of the film samples were character-ized and analyzed by using scanning electron microscope,Raman spectroscopy and X-ray photoelectron spectroscopy.The res-ults showed that tungsten telluride thin films with good crystal orientation in(001)were obtained at telluride temperature of 550℃.When the telluride temperature reached 570℃,the tungsten telluride began to decompose and unsaturated mag-netoresistance was found.
文摘某大水型金属矿山帷幕注浆工程中应用的黏土-水泥浆液水化反应后的pH值高达13,表现为强碱性,对地下水及地表水构成了潜在污染风险。为探究低碱性外加剂对该矿山水害防治帷幕注浆工程中黏土-水泥浆液性能的调控机制,采用正交试验设计,系统分析了不同配比条件下浆液的流变特性,包括流动性、泵送性能、凝结时间及pH值的变化规律。通过分别引入磷石膏、粉煤灰及降碱外加剂(substance of Jin Pin,SJP),探讨不同材料在降低浆液碱性方面的有效性。试验结果显示:磷石膏能够将浆液pH值有效降低至11,同时延长凝结时间;粉煤灰虽在降低浆液碱度方面效果有限,却改善了浆液的泵送性能并缩短了泵送期限;SJP外掺剂在降低p H值和延长泵送期方面表现突出,当掺量由2.5%增加至3.5%时,浆液pH值显著降低至8。基于试验数据,优化了SJP外掺剂-粉质黏土-磷石膏-水泥配方,并通过正交试验确定了最优配比:复合酸式盐0.5%、硫铝酸盐1.5%、磷石膏10.0%、黏土50.0%。该优化配方制备的浆液p H值降低至10,流动度保持在18~23 cm,泵送期延长至100~220 min,充分满足工程应用需求。研究结果可为帷幕注浆工程中通过控制浆液碱性减少环境污染提供了科学依据。
