The microemulsion copolymerizations of acrylic acid (AA),acrylamide (AM),N-methylol acrylamide (NMA),methylmethacrylate (MMA),butyl acrylate (BA) and acrylonitrile (AN) initiated by the redox initiator ammonium persul...The microemulsion copolymerizations of acrylic acid (AA),acrylamide (AM),N-methylol acrylamide (NMA),methylmethacrylate (MMA),butyl acrylate (BA) and acrylonitrile (AN) initiated by the redox initiator ammonium persulfate (APS) and N,N,N′,N′-tetramethylethylenediamine (TMEDA) at ambient temperature were investigated.With this process high solids-content (44.0 wt%) and small (less than 50 nm) particle diameter copolymer latexes were attained.The effects of surfactants,the mechanical stabilities and application properties as an environmentally friendly self-crosslinking pigment printing binder with multifunctional groups were studied.展开更多
The dissolution kinetics of calcined ulexite in ammonium chloride solutions at high solid-to-liquid ratios were investigated. In the experiments, calcination temperature, solution concentration, reaction temperature, ...The dissolution kinetics of calcined ulexite in ammonium chloride solutions at high solid-to-liquid ratios were investigated. In the experiments, calcination temperature, solution concentration, reaction temperature, and pre-hydration were chosen as parameters. It was observed that the dissolution rate increased with increasing calcination temperature, solution concentration, and reaction temperature, whereas it was not affected by pre-hydration. Employing graphical and statistic methods, the dissolution rate, based on homogeneous reaction model, can be given as: (1-X(B2O3))-1-1= k(c(NH4Cl))1.982t. The activation energy for the dissolution of the ulexite sample calcined at 160 ℃ was found to be 84.04 kJ·mol-1.展开更多
The combustion (ballistic) properties of a high solid loading composite solid propellant family (Butalites) was studied experimentally by using propellant formulations based on hydroxy-terminated polybutadiene pre...The combustion (ballistic) properties of a high solid loading composite solid propellant family (Butalites) was studied experimentally by using propellant formulations based on hydroxy-terminated polybutadiene pre-polymer (HTPB) as a fuel binder main backbone, bimodal system ammonium perchlorate oxidizer (AP) and aluminum powder (AI) as metallic fuel. Burning rates were doubled at various pressures, when solids loading (AP and 17% A1) were increased from 80 to 88% and the measured characteristic velocity values were increased by about 100m/sec. The pressure exponent (n) values were lower with 80-85% solids loading. The burning rates were increased by about 2-5% when comparing the data obtained by static firing with those obtained by the strand burner method.展开更多
Ammonium sulfate residue is a particulate solid and is produced during the manufacture of ammonium sulfate fertilizer. The residue used in this study contained a large portion of calcium carbonate, from which active l...Ammonium sulfate residue is a particulate solid and is produced during the manufacture of ammonium sulfate fertilizer. The residue used in this study contained a large portion of calcium carbonate, from which active lime (CaO) was recovered via thermal decomposition. We used a purpose-built device to decom- pose the residue in a semi-suspension state. We found that CaO had the highest activity when residue was decomposed at 850-900 ~C. Our experiments indicated that ammonium sulfate residue should be decom- posed in a suspension state to produce active CaO. Based on our laboratory test findings, an industrial-scale production line with a high solid/gas ratio in a suspension state was devised. The optimal operating con- ditions for the decomposition of the ammonium sulfate residue to produce high quality CaO were also investigated.We found that the CaCO3 decomposition rate was high and the CaO product was highly active, averaging 170 s by the citric acid method. Morphology measurements showed that the CaO product had a porous structure and a large specific surface ensuring high activity.展开更多
In this work,we developed a continuous preparation strategy for the production of high-solidscontent waterborne polyurethane(WPU)emulsions via high-gravity-assisted emulsification in a rotating packed bed(RPB)reactor....In this work,we developed a continuous preparation strategy for the production of high-solidscontent waterborne polyurethane(WPU)emulsions via high-gravity-assisted emulsification in a rotating packed bed(RPB)reactor.By adjusting the experimental parameters and formula,WPU emulsions with a high solids content of 55%and alow viscosity were prepared.Preliminary applications of the high-solids-content WPU as a thermally insulating material were demonstrated.RPB emulsification is an economical and environmentally friendly production strategy because of the low energy consumption,short emulsification time,and effective devolatilization.This study demonstrated an effective method for preparation of high-solids-content WPU,moving toward commercialization and industrialization.展开更多
A novel organic fluorophor with high solid state luminescent efficiency based on 1,4-bis(2,2-di(pyridin-2-yl)- vinyl)benzene (BDP2VB) was designed and synthesized. It emits faintly in solution, but becomes a str...A novel organic fluorophor with high solid state luminescent efficiency based on 1,4-bis(2,2-di(pyridin-2-yl)- vinyl)benzene (BDP2VB) was designed and synthesized. It emits faintly in solution, but becomes a strong emitter in the aggregate state, demonstrating its aggregation induced emission (AIE) property. According to the crystal struc- ture analysis, J-type aggregation was formed in the packing mode of the molecule, which was demonstrated to be beneficial to gain high fluorescent quantum efficiency in solid state. Additionally, the emission color of BDP2VB can change dramatically in solid state as well as in solution by the protonation stimuli.展开更多
High solid content CO_(2)-based cationic waterborne polyurethanes(CWPUs)were prepared using CO_(2)-polyols as soft segment and Nmethyl diethanolamine(MDEA)as hydrophilic group.The resulting stable aqueous dispersion d...High solid content CO_(2)-based cationic waterborne polyurethanes(CWPUs)were prepared using CO_(2)-polyols as soft segment and Nmethyl diethanolamine(MDEA)as hydrophilic group.The resulting stable aqueous dispersion displayed a high solid content of 52%with a low MDEA loading of 3.52 wt%.This novel structural CWPU can provide excellent adhesive strength,whose T-peel strength could reach 173.48N/5cm,20%higher than that of ester-based cationic waterborne polyurethane(87.55 N/5cm).The CO_(2)-based CWPU film showed only 2 wt%swelling percentage after 240 min immersion in water,and no change was observed during its immersion in 5 wt%sodium hydroxide solution.The tensile strength of CO_(2)-WPUs dropped slowly to 91.2%after 480 min immersion in a 5 wt%sodium hydroxide solution,whereas that of esterbased CWPUs dropped quickly to 32%after 240 min and their mechanical properties were lost after 360 min immersion.Meanwhile,the retention of the tensile strength of the CO_(2)-CWPUs was 81.5%even after 720 min immersion in 10 wt%H_(2)O_(2) solution,while it was only ca.38%for the ester-based CWPUs.These results indicated that the cationic CO_(2)-based CWPU may be promising waterborne adhesive with outstanding ageing resistance due to its synergistic effect from carbonate and ether groups of CO_(2)-polyol structure.展开更多
Anaerobic co-digestion of food waste(FW) and rice straw(RS) in continuously stirred tank reactor(CSTR) at high organic loading rate(OLR) was investigated. Co-digestion studies of FW and RS with six different m...Anaerobic co-digestion of food waste(FW) and rice straw(RS) in continuously stirred tank reactor(CSTR) at high organic loading rate(OLR) was investigated. Co-digestion studies of FW and RS with six different mixing ratios were conducted at an initial volatile solid(VS) concentration of more than 3 g VS · L-1. The biogas production, methane contents, degradation efficiency of VS, chemical oxygen demand(COD) and volatile fatty acids(VFAs) were determined to evaluate the stability and performance of the system. The results showed that the co-digestion process had higher system stability and higher volumetric biogas production than mono-digestions. Increase in FW content in the feedstock could increase the methane yield and shorten retention time. The efficiency of co-digestion systems mainly relied on the mixing ratios of FW and RS to some extent. The highest methane yield was 60.55 m L· g V· S-1 · d-1 at a mass ratio(FW/RS) of 3 : 1, which was 178% and 70% higher than that of mono-digestions of FW and RS, respectively. Consequently, the anaerobic co-digestion of FW and RS could have superior stability and better performance than monodigestions in higher organic loading system.展开更多
Stable high-solids-content acrylate emulsion were obtained with a nonionic polymerizable emulsifier allyloxy nonylphenoxy poly (ethyleneoxy) (10) ether (ANPEO10), and a conventional emulsifier OP-10 as a referen...Stable high-solids-content acrylate emulsion were obtained with a nonionic polymerizable emulsifier allyloxy nonylphenoxy poly (ethyleneoxy) (10) ether (ANPEO10), and a conventional emulsifier OP-10 as a reference sample. 1H NMR proves that the polymerizable emulsifier ANPEO10 has been incorporated into the resulted acrylate polymers. TEM demonstrates that there are some differences in the particle morphologies. AFM proves that the polymerizable emulsifier ANPEO10 migrating to the surface of the emulsion film was much less than the conventional emulsifier OP-10. The polymerizable emulsifier ANPEO10 can enhance the adhesion with glass plate compared to the conventional emulsifier. Furthermore, with increasing amount of emulsifier, the surface free energy of the films first decreased and then increased, and the adhesion with glass plate is initially enhanced and then attenuated. The water-resistance and solvent-resistance of the films prepared by the polymerizable emulsifier ANPEO10 are superior to those prepared by the conventional emulsifier OP-10.展开更多
Radioiodine-131 is one of the pernicious radionuclides released during nuclear accidents, as its radioactivity can potentially affect public health and safety.To prevent radioiodine-131 from being released into the en...Radioiodine-131 is one of the pernicious radionuclides released during nuclear accidents, as its radioactivity can potentially affect public health and safety.To prevent radioiodine-131 from being released into the environment, the use of adsorbents that are highly efficient at high temperatures is significantly important. The radioactive gas from the nuclear core in an accident, such as the Fukushima nuclear accident, is usually released occurs under high-temperature conditions. Therefore, in this study, a 10 wt% silver phosphate-loaded alumina(Ag_3 PO_4/Al_2 O_3) adsorbent was prepared. Further, its performance toward radioiodine adsorption was tested at high temperatures up to 750 0 C, using Al_2 O_3 and traditional 10 wt% Ag/Al_2 O_3 adsorbent as controls. The results of the iodine adsorption test indicated that the 10 wt% Ag_3 PO_4/Al_2 O_3 adsorbent showed a higher decontamination factor than did the 10 wt% Ag/Al_2 O_3 adsorbent by two orders of magnitude at 650 and 750℃. Results of the iodine desorption test revealed that the new adsorbent could be effectively used at 750 ℃. The characteristic powder X-ray diffraction, nitrogen adsorption-desorption isotherm,X-ray photoelectron spectroscopy, and thermogravimetric analysis-differential scanning calorimetry data indicated that the enhanced adsorption ability at high temperatures was attributed to the formation of a solid solution between silver iodide and Ag_3 PO_4.展开更多
The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at var...The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at various heating and cooling rates. Then, the effects of high-pressure heat treatments on the solid-state phase transformation and the microstructures of Cu61.13Zn33.94A14.93 alloys were investigated. The results show that high-pressure heat treatments can refine the grains and can change the preferred orientation from (111) to (200) of α phase. Compared with the as-cast alloy, the sample with high-pressure heat treatment has finer grains, lower β'→β and/β→β' transformation temperature and activation energy. Furthermore, we found that high cooling rate favours the formation of fine needle-like α phase in the range of 5-20℃/min.展开更多
The nondendritic semi-solid slurry preparation of high chromium cast iron Cr20Mo2 has been studied in this paper. The experiments show that the proeutectic austenitic particles are more spherical under a larger stirri...The nondendritic semi-solid slurry preparation of high chromium cast iron Cr20Mo2 has been studied in this paper. The experiments show that the proeutectic austenitic particles are more spherical under a larger stirring power condition, even if the stirring time is shorter, while the proeutectic austenitic particles are not very much spherical under a smaller stirring power condition and some proeutectic austenitic dendrites also exist, even if the stirring time is very long. The experiments also show that when stirred for 5-6 minutes under the test condition, the semi-solid slurry with 40vol.%-50vol.% solid fraction and spherical proeutectic austenite in the size of 50-80μm can be obtained.展开更多
A rheometer for semi-solid high-melting point alloys was developed based on the principle of a double-bucket rheometer, with which the solidifying of semi-solid high-melting point alloy melt could be effectively contr...A rheometer for semi-solid high-melting point alloys was developed based on the principle of a double-bucket rheometer, with which the solidifying of semi-solid high-melting point alloy melt could be effectively controlled by the control of temperature and the outer force-field; and different microstructures have also been obtained. This rheometer can be used to investigate the rheological behavior under different conditions by changing the Theological parameters. By way of full-duplex communication between the computer and each sensor, automatic control of the test equipment and real- time measurement of rheological parameters were realized. Finally, the influencing factors on torque are also quantitatively analyzed .展开更多
The semi-solid high carbon steel T12 was rolled in a closed box groove under a certain condition by the rheo-rolling equipment, and the microstructural morphology of the semi-solid T12 before and after deformation wa...The semi-solid high carbon steel T12 was rolled in a closed box groove under a certain condition by the rheo-rolling equipment, and the microstructural morphology of the semi-solid T12 before and after deformation was investigated by optical mi- croscope to analyze and summarize the microstructure evolution law of T12 deformed in semi-solid state. The experiment results show that the grain shape before deformation of the semi-solid T12 steel displays globule or ellipse by the electromagnetic stirring, the distribution of solid and liquid phases is homogeneous. But the microstructure of semi-solid product after rheo-rolling exhibits macrosegregation that the distribution of liquid and solid phases changes, the liquid phases divorce from the solid phases. In the transverse section, most of the solid phases get together in the center of the specimen, the liquid phases flow to the surface or the edge of the specimen, and the grains occur plastic deformation while reduction increased. In longitudinal section, the middle micro- structure of the specimen is more homogeneous than that at the head or tail, the head microstructure is similar to the tail and the size of the grains is not homogeneous.展开更多
Two 9,10-distyrylanthracene (DSA) derivatives CNDSA and t-BUDSA were designed and synthesized, and their photophysical properties and crystal structures were investigated. Compared to DSA, the maximum emission peaks o...Two 9,10-distyrylanthracene (DSA) derivatives CNDSA and t-BUDSA were designed and synthesized, and their photophysical properties and crystal structures were investigated. Compared to DSA, the maximum emission peaks of the two compounds showed red-shift not only in THF solution, but also in crystals, because the introduction of electron-withdrawing substituents to DSA leads to more dispersion of the electrons in the molecules. The two crystals of CNDSA and t-BUDSA show strong fluores- cence with the efficiency F of 45% and 33%, respectively, which may be resulted from no obvious-interactions between molecules inside the crystal due to the large distance between the two adjacent molecules and nearly no overlap between the central anthracene planes. The analysis of crystal structures of the two compounds indicated that the molecules are arranged in the same conformation and orientation in their crystals, i.e. uniaxially oriented packing crystal, because of the supramolecular interac- tion of CH/ in the two crystals and additional C-H···N interactions in CNDSA.展开更多
Semi-solid casting of M2 high speed steel ingots was investigated by inclined slope pre-crystallization method. Effects of casting temperature and slope length on the microstructure of M2 HSS ingots were investigated....Semi-solid casting of M2 high speed steel ingots was investigated by inclined slope pre-crystallization method. Effects of casting temperature and slope length on the microstructure of M2 HSS ingots were investigated. M2 cast ingots of non-dendritic primary austenite and fine eutectic ledeburite network carbide structure were obtained, with the casting temperature, slope length and angle of 1480 ℃, 500 mm and 60° respectively. Meanwhile, the microstructure of cast samples was quantitatively assessed by Image tool software. Results show that optimum mean equivalent diameter of primary austenite crystal grain is 50.8 μm, shape factor is 0.83, and mean thickness of network carbide is 5.21 μm.展开更多
The seeded semicontinuous emulsion multi-copolymerization of butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), methyl methacrylate (MMA), 2-hydroxyl propyl acrylate (HOPA) and acrylic acid (AA) was used to prepare th...The seeded semicontinuous emulsion multi-copolymerization of butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), methyl methacrylate (MMA), 2-hydroxyl propyl acrylate (HOPA) and acrylic acid (AA) was used to prepare the acrylic latexes with high-solid content. The effects of monomer emulsion feed rates (R(a)) and (R/E)(E) values, the ratio of emulsifier amount between the initial charge (R) and the addition monomer emulsion (E), on the polymerization reaction features, the viscosities, surface tensions,particle sizes and particle sizes distributions of latexes, T-g and the insoluble fractions of films, the 180 degrees peel strength, tack and holding power of pressure-sensitive adhesive (PSA) tapes, prepared from the latexes, were studied. Experimental study shows that the grafting and crosslinking fraction in the PSA tapes must be controlled within a suitable range to keep the balance of the 180 degrees peel strength, tack and holding power.展开更多
The high water content of municipal solid waste(MSW)will reduce the effciency of mechanical sorting,consequently unfavorable for beneficial utilization.In this study,a combined hydrolytic-aerobic biodrying technology ...The high water content of municipal solid waste(MSW)will reduce the effciency of mechanical sorting,consequently unfavorable for beneficial utilization.In this study,a combined hydrolytic-aerobic biodrying technology was introduced to remove water from MSW.The total water removals were proved to depend on the ventilation frequency and the temporal span in the hydrolytic stage. The ventilation frequency of 6 times/d was preferable in the hydrolytic stage.The hydrolytic span should not be prolonged more than ...展开更多
An experimental investigation is carried out to machine SiC ceramic material through the method of high speed plane lapping with solid(fixed) abrasives after the critical condition of brittle-ductile transition is the...An experimental investigation is carried out to machine SiC ceramic material through the method of high speed plane lapping with solid(fixed) abrasives after the critical condition of brittle-ductile transition is theoretically analyzed. The results show that the material removal mechanism and the surface roughness are chiefly related to the granularity of abrasives for brittle materials such as SiC ceramic. It is easily realized to machine SiC ceramic in the ductile mode using W3.5 grit and a high efficiency, low cost and smooth surface with a surface roughness of R_a 2.4?nm can be achieved.展开更多
文摘The microemulsion copolymerizations of acrylic acid (AA),acrylamide (AM),N-methylol acrylamide (NMA),methylmethacrylate (MMA),butyl acrylate (BA) and acrylonitrile (AN) initiated by the redox initiator ammonium persulfate (APS) and N,N,N′,N′-tetramethylethylenediamine (TMEDA) at ambient temperature were investigated.With this process high solids-content (44.0 wt%) and small (less than 50 nm) particle diameter copolymer latexes were attained.The effects of surfactants,the mechanical stabilities and application properties as an environmentally friendly self-crosslinking pigment printing binder with multifunctional groups were studied.
文摘The dissolution kinetics of calcined ulexite in ammonium chloride solutions at high solid-to-liquid ratios were investigated. In the experiments, calcination temperature, solution concentration, reaction temperature, and pre-hydration were chosen as parameters. It was observed that the dissolution rate increased with increasing calcination temperature, solution concentration, and reaction temperature, whereas it was not affected by pre-hydration. Employing graphical and statistic methods, the dissolution rate, based on homogeneous reaction model, can be given as: (1-X(B2O3))-1-1= k(c(NH4Cl))1.982t. The activation energy for the dissolution of the ulexite sample calcined at 160 ℃ was found to be 84.04 kJ·mol-1.
文摘The combustion (ballistic) properties of a high solid loading composite solid propellant family (Butalites) was studied experimentally by using propellant formulations based on hydroxy-terminated polybutadiene pre-polymer (HTPB) as a fuel binder main backbone, bimodal system ammonium perchlorate oxidizer (AP) and aluminum powder (AI) as metallic fuel. Burning rates were doubled at various pressures, when solids loading (AP and 17% A1) were increased from 80 to 88% and the measured characteristic velocity values were increased by about 100m/sec. The pressure exponent (n) values were lower with 80-85% solids loading. The burning rates were increased by about 2-5% when comparing the data obtained by static firing with those obtained by the strand burner method.
基金Wengfu Phosphate Fertilizer Plant(WPFP),WengFu(Group) Co.,Ltd,Guizhou,China for financial supportgrants from National Science and Technology Support Program(No.2012BAA08B00)Science and Technology Integrated Innovation Project of Shaanxi Province(No.2012KTZB03-04)
文摘Ammonium sulfate residue is a particulate solid and is produced during the manufacture of ammonium sulfate fertilizer. The residue used in this study contained a large portion of calcium carbonate, from which active lime (CaO) was recovered via thermal decomposition. We used a purpose-built device to decom- pose the residue in a semi-suspension state. We found that CaO had the highest activity when residue was decomposed at 850-900 ~C. Our experiments indicated that ammonium sulfate residue should be decom- posed in a suspension state to produce active CaO. Based on our laboratory test findings, an industrial-scale production line with a high solid/gas ratio in a suspension state was devised. The optimal operating con- ditions for the decomposition of the ammonium sulfate residue to produce high quality CaO were also investigated.We found that the CaCO3 decomposition rate was high and the CaO product was highly active, averaging 170 s by the citric acid method. Morphology measurements showed that the CaO product had a porous structure and a large specific surface ensuring high activity.
基金the National Key Research and Development Program of China(Grant Nos.2017YFB-0404302 and 2017YFB0404300).
文摘In this work,we developed a continuous preparation strategy for the production of high-solidscontent waterborne polyurethane(WPU)emulsions via high-gravity-assisted emulsification in a rotating packed bed(RPB)reactor.By adjusting the experimental parameters and formula,WPU emulsions with a high solids content of 55%and alow viscosity were prepared.Preliminary applications of the high-solids-content WPU as a thermally insulating material were demonstrated.RPB emulsification is an economical and environmentally friendly production strategy because of the low energy consumption,short emulsification time,and effective devolatilization.This study demonstrated an effective method for preparation of high-solids-content WPU,moving toward commercialization and industrialization.
基金973 Program,the National Natural Science Foundation of China,the Research Fund for the Doctoral Program of Higher Education of China,the Project of Jilin Province
文摘A novel organic fluorophor with high solid state luminescent efficiency based on 1,4-bis(2,2-di(pyridin-2-yl)- vinyl)benzene (BDP2VB) was designed and synthesized. It emits faintly in solution, but becomes a strong emitter in the aggregate state, demonstrating its aggregation induced emission (AIE) property. According to the crystal struc- ture analysis, J-type aggregation was formed in the packing mode of the molecule, which was demonstrated to be beneficial to gain high fluorescent quantum efficiency in solid state. Additionally, the emission color of BDP2VB can change dramatically in solid state as well as in solution by the protonation stimuli.
基金financially supported by the National Natural Science Foundation of China(No.32071686)。
文摘High solid content CO_(2)-based cationic waterborne polyurethanes(CWPUs)were prepared using CO_(2)-polyols as soft segment and Nmethyl diethanolamine(MDEA)as hydrophilic group.The resulting stable aqueous dispersion displayed a high solid content of 52%with a low MDEA loading of 3.52 wt%.This novel structural CWPU can provide excellent adhesive strength,whose T-peel strength could reach 173.48N/5cm,20%higher than that of ester-based cationic waterborne polyurethane(87.55 N/5cm).The CO_(2)-based CWPU film showed only 2 wt%swelling percentage after 240 min immersion in water,and no change was observed during its immersion in 5 wt%sodium hydroxide solution.The tensile strength of CO_(2)-WPUs dropped slowly to 91.2%after 480 min immersion in a 5 wt%sodium hydroxide solution,whereas that of esterbased CWPUs dropped quickly to 32%after 240 min and their mechanical properties were lost after 360 min immersion.Meanwhile,the retention of the tensile strength of the CO_(2)-CWPUs was 81.5%even after 720 min immersion in 10 wt%H_(2)O_(2) solution,while it was only ca.38%for the ester-based CWPUs.These results indicated that the cationic CO_(2)-based CWPU may be promising waterborne adhesive with outstanding ageing resistance due to its synergistic effect from carbonate and ether groups of CO_(2)-polyol structure.
基金Supported by the Natural Science Foundation of Heilongjiang Province(QC2014C031)Returned Overseas Foundation of Heilongjiang Province(LC2013C07)+2 种基金Outstanding Academic Leaders Foundation of Harbin City(2013RFXYJ015)Young Reserve Talent Foundation of Harbin City(2014RFQYJ141)Outstanding Young Foundation of Heilongjiang Academy of Agricultural Sciences(2013JCQN003)
文摘Anaerobic co-digestion of food waste(FW) and rice straw(RS) in continuously stirred tank reactor(CSTR) at high organic loading rate(OLR) was investigated. Co-digestion studies of FW and RS with six different mixing ratios were conducted at an initial volatile solid(VS) concentration of more than 3 g VS · L-1. The biogas production, methane contents, degradation efficiency of VS, chemical oxygen demand(COD) and volatile fatty acids(VFAs) were determined to evaluate the stability and performance of the system. The results showed that the co-digestion process had higher system stability and higher volumetric biogas production than mono-digestions. Increase in FW content in the feedstock could increase the methane yield and shorten retention time. The efficiency of co-digestion systems mainly relied on the mixing ratios of FW and RS to some extent. The highest methane yield was 60.55 m L· g V· S-1 · d-1 at a mass ratio(FW/RS) of 3 : 1, which was 178% and 70% higher than that of mono-digestions of FW and RS, respectively. Consequently, the anaerobic co-digestion of FW and RS could have superior stability and better performance than monodigestions in higher organic loading system.
基金Funded by Ministry of Education (No.2006-KL-008),and Qingxin Hanerchem Chemical Technology Co,Ltd.
文摘Stable high-solids-content acrylate emulsion were obtained with a nonionic polymerizable emulsifier allyloxy nonylphenoxy poly (ethyleneoxy) (10) ether (ANPEO10), and a conventional emulsifier OP-10 as a reference sample. 1H NMR proves that the polymerizable emulsifier ANPEO10 has been incorporated into the resulted acrylate polymers. TEM demonstrates that there are some differences in the particle morphologies. AFM proves that the polymerizable emulsifier ANPEO10 migrating to the surface of the emulsion film was much less than the conventional emulsifier OP-10. The polymerizable emulsifier ANPEO10 can enhance the adhesion with glass plate compared to the conventional emulsifier. Furthermore, with increasing amount of emulsifier, the surface free energy of the films first decreased and then increased, and the adhesion with glass plate is initially enhanced and then attenuated. The water-resistance and solvent-resistance of the films prepared by the polymerizable emulsifier ANPEO10 are superior to those prepared by the conventional emulsifier OP-10.
基金supported by the National Natural Science Foundation of China(Nos.11575010 and 21201013)
文摘Radioiodine-131 is one of the pernicious radionuclides released during nuclear accidents, as its radioactivity can potentially affect public health and safety.To prevent radioiodine-131 from being released into the environment, the use of adsorbents that are highly efficient at high temperatures is significantly important. The radioactive gas from the nuclear core in an accident, such as the Fukushima nuclear accident, is usually released occurs under high-temperature conditions. Therefore, in this study, a 10 wt% silver phosphate-loaded alumina(Ag_3 PO_4/Al_2 O_3) adsorbent was prepared. Further, its performance toward radioiodine adsorption was tested at high temperatures up to 750 0 C, using Al_2 O_3 and traditional 10 wt% Ag/Al_2 O_3 adsorbent as controls. The results of the iodine adsorption test indicated that the 10 wt% Ag_3 PO_4/Al_2 O_3 adsorbent showed a higher decontamination factor than did the 10 wt% Ag/Al_2 O_3 adsorbent by two orders of magnitude at 650 and 750℃. Results of the iodine desorption test revealed that the new adsorbent could be effectively used at 750 ℃. The characteristic powder X-ray diffraction, nitrogen adsorption-desorption isotherm,X-ray photoelectron spectroscopy, and thermogravimetric analysis-differential scanning calorimetry data indicated that the enhanced adsorption ability at high temperatures was attributed to the formation of a solid solution between silver iodide and Ag_3 PO_4.
文摘The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at various heating and cooling rates. Then, the effects of high-pressure heat treatments on the solid-state phase transformation and the microstructures of Cu61.13Zn33.94A14.93 alloys were investigated. The results show that high-pressure heat treatments can refine the grains and can change the preferred orientation from (111) to (200) of α phase. Compared with the as-cast alloy, the sample with high-pressure heat treatment has finer grains, lower β'→β and/β→β' transformation temperature and activation energy. Furthermore, we found that high cooling rate favours the formation of fine needle-like α phase in the range of 5-20℃/min.
基金supported by the National Natural Science Foundation of China(No.59995440)
文摘The nondendritic semi-solid slurry preparation of high chromium cast iron Cr20Mo2 has been studied in this paper. The experiments show that the proeutectic austenitic particles are more spherical under a larger stirring power condition, even if the stirring time is shorter, while the proeutectic austenitic particles are not very much spherical under a smaller stirring power condition and some proeutectic austenitic dendrites also exist, even if the stirring time is very long. The experiments also show that when stirred for 5-6 minutes under the test condition, the semi-solid slurry with 40vol.%-50vol.% solid fraction and spherical proeutectic austenite in the size of 50-80μm can be obtained.
文摘A rheometer for semi-solid high-melting point alloys was developed based on the principle of a double-bucket rheometer, with which the solidifying of semi-solid high-melting point alloy melt could be effectively controlled by the control of temperature and the outer force-field; and different microstructures have also been obtained. This rheometer can be used to investigate the rheological behavior under different conditions by changing the Theological parameters. By way of full-duplex communication between the computer and each sensor, automatic control of the test equipment and real- time measurement of rheological parameters were realized. Finally, the influencing factors on torque are also quantitatively analyzed .
基金This work was financially supported by the National Natural Science Foundation of China and Baosteel (No.50174003).
文摘The semi-solid high carbon steel T12 was rolled in a closed box groove under a certain condition by the rheo-rolling equipment, and the microstructural morphology of the semi-solid T12 before and after deformation was investigated by optical mi- croscope to analyze and summarize the microstructure evolution law of T12 deformed in semi-solid state. The experiment results show that the grain shape before deformation of the semi-solid T12 steel displays globule or ellipse by the electromagnetic stirring, the distribution of solid and liquid phases is homogeneous. But the microstructure of semi-solid product after rheo-rolling exhibits macrosegregation that the distribution of liquid and solid phases changes, the liquid phases divorce from the solid phases. In the transverse section, most of the solid phases get together in the center of the specimen, the liquid phases flow to the surface or the edge of the specimen, and the grains occur plastic deformation while reduction increased. In longitudinal section, the middle micro- structure of the specimen is more homogeneous than that at the head or tail, the head microstructure is similar to the tail and the size of the grains is not homogeneous.
基金supported by the National Basic Research Program of China(2013CB834702)the National Natural Science Foundation of China(21074045,21204027,21221063)+1 种基金the Research Fund for the Doctoral Program of Higher Education of Chinathe Project of Jilin Province(20100704)
文摘Two 9,10-distyrylanthracene (DSA) derivatives CNDSA and t-BUDSA were designed and synthesized, and their photophysical properties and crystal structures were investigated. Compared to DSA, the maximum emission peaks of the two compounds showed red-shift not only in THF solution, but also in crystals, because the introduction of electron-withdrawing substituents to DSA leads to more dispersion of the electrons in the molecules. The two crystals of CNDSA and t-BUDSA show strong fluores- cence with the efficiency F of 45% and 33%, respectively, which may be resulted from no obvious-interactions between molecules inside the crystal due to the large distance between the two adjacent molecules and nearly no overlap between the central anthracene planes. The analysis of crystal structures of the two compounds indicated that the molecules are arranged in the same conformation and orientation in their crystals, i.e. uniaxially oriented packing crystal, because of the supramolecular interac- tion of CH/ in the two crystals and additional C-H···N interactions in CNDSA.
基金Funded by the Science Foundation of Beijing Jiaotong University (No.230-12)
文摘Semi-solid casting of M2 high speed steel ingots was investigated by inclined slope pre-crystallization method. Effects of casting temperature and slope length on the microstructure of M2 HSS ingots were investigated. M2 cast ingots of non-dendritic primary austenite and fine eutectic ledeburite network carbide structure were obtained, with the casting temperature, slope length and angle of 1480 ℃, 500 mm and 60° respectively. Meanwhile, the microstructure of cast samples was quantitatively assessed by Image tool software. Results show that optimum mean equivalent diameter of primary austenite crystal grain is 50.8 μm, shape factor is 0.83, and mean thickness of network carbide is 5.21 μm.
基金This work was supported by the National Natural Science Foundation of China
文摘The seeded semicontinuous emulsion multi-copolymerization of butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), methyl methacrylate (MMA), 2-hydroxyl propyl acrylate (HOPA) and acrylic acid (AA) was used to prepare the acrylic latexes with high-solid content. The effects of monomer emulsion feed rates (R(a)) and (R/E)(E) values, the ratio of emulsifier amount between the initial charge (R) and the addition monomer emulsion (E), on the polymerization reaction features, the viscosities, surface tensions,particle sizes and particle sizes distributions of latexes, T-g and the insoluble fractions of films, the 180 degrees peel strength, tack and holding power of pressure-sensitive adhesive (PSA) tapes, prepared from the latexes, were studied. Experimental study shows that the grafting and crosslinking fraction in the PSA tapes must be controlled within a suitable range to keep the balance of the 180 degrees peel strength, tack and holding power.
基金supported by the National Key Technolo-gy R&D Program(No.2006BAC06B04,2006BAC02A03)the Key Grant Project of Shanghai Committee of Science and Technology(No.06dz12308).
文摘The high water content of municipal solid waste(MSW)will reduce the effciency of mechanical sorting,consequently unfavorable for beneficial utilization.In this study,a combined hydrolytic-aerobic biodrying technology was introduced to remove water from MSW.The total water removals were proved to depend on the ventilation frequency and the temporal span in the hydrolytic stage. The ventilation frequency of 6 times/d was preferable in the hydrolytic stage.The hydrolytic span should not be prolonged more than ...
文摘An experimental investigation is carried out to machine SiC ceramic material through the method of high speed plane lapping with solid(fixed) abrasives after the critical condition of brittle-ductile transition is theoretically analyzed. The results show that the material removal mechanism and the surface roughness are chiefly related to the granularity of abrasives for brittle materials such as SiC ceramic. It is easily realized to machine SiC ceramic in the ductile mode using W3.5 grit and a high efficiency, low cost and smooth surface with a surface roughness of R_a 2.4?nm can be achieved.