Lime pretreated phosphogypsum(PG) was calcined at 500 ℃ to produce anhydrate gypsum cement. Due to the slow hydration of anhydrate gypsum, additives, K2SO4 and hemihydrate gypsum were selected to accelerate the hyd...Lime pretreated phosphogypsum(PG) was calcined at 500 ℃ to produce anhydrate gypsum cement. Due to the slow hydration of anhydrate gypsum, additives, K2SO4 and hemihydrate gypsum were selected to accelerate the hydration of anhydrate. The hydration characteristics, the resistance to hydrodynamic water, and the mineralogical studies were investigated. The experimental results suggest that activated by K2SO4 and hemihydrate, anhydrate PG hydrates much more rapidly than that in the presence of only K2SO4 or in the absence of additives. The binder has proper setting time, good strength development, and relatively better resistance to water. The hardened binder has hydrated products of rod or stick like shaped dihydrate gypsum crystals.展开更多
Phosphogypsum(PG) calcined at 500 ℃ was activated by K2SO4 and salt lime with loose structure as seed crystal. To determine the effect of activation, hydration of the anhydrate PG activated was investigated by exam...Phosphogypsum(PG) calcined at 500 ℃ was activated by K2SO4 and salt lime with loose structure as seed crystal. To determine the effect of activation, hydration of the anhydrate PG activated was investigated by examination of the setting time, the proportion of hydrated anhydrate PG, the microstructure of the hardenite and the resistance to water. Results show that activated anhydrate PG hydrates much more rapidly than that in the absence of activators. The activated anhydrate PG has proper setting time and hydrated proportion. The resistance to water was greatly improved. SEM photos show that the set activated PG has hydrated products of rod-like and closely connected crystals. The different addition of activator leads to different compact structure.展开更多
In this work,phosphogypsum(PG) with a small amount of lime was thermally pretreated at 450 ℃ to produce anhydrate gypsum for the purpose of searching new ways for utilization of waste PG. Additives,K2SO4 and one sele...In this work,phosphogypsum(PG) with a small amount of lime was thermally pretreated at 450 ℃ to produce anhydrate gypsum for the purpose of searching new ways for utilization of waste PG. Additives,K2SO4 and one selected seed crystal(SC),were used as activator for anhydrate PG. The hydration characteristics of the anhydrate PG binders were investigated by determination of the setting time,the ratio of hydrated anhydrate PG,the compressive strength development,and the microstructure of the hardenite. The resistance to water was studied by measuring mass loss of binders exposed to hydrodynamic water. Results suggest that activated by K2SO4 and SC,anhydrate PG hydrates much more rapidly than that without additives. The anhydrate PG binder with K2SO4 and SC has proper setting time and good strength developments. SEM photos show that the set binders have hydrated products of rodlike and regularly shaped crystals. Those crystals connected closely,and the hardenite has a compact structure,which is beneficial to the obtainment of good properties.展开更多
Given the increased circulation time after fishing,a series of changes take place in live clams,leading to a deterioration in quality even after death.Thus,in this study,we aimed to explore the optimal mode of transpo...Given the increased circulation time after fishing,a series of changes take place in live clams,leading to a deterioration in quality even after death.Thus,in this study,we aimed to explore the optimal mode of transportation of clams.The container for holding clams was reformed,and a water circulation temperature control system was established.The physiological responses of clams during anhydrous and watery transportation at two temperatures(4 and 15℃)were investigated based on the aforementioned system.When comparing the transportation patterns after 3 d of transport,a higher survival rate was observed at 4℃(97%)than at 15℃(63%)in the anhydrous transportation groups and a lower survival rate was observed at 4℃(93%)than at 15℃(99%)in the watery transportation groups.In addition,the glycogen content,condition index(CI),and adenylate energy charge(A.E.C)value were higher at4℃((40.87±0.99)mg g^(-1),13.71%±0.50%and 57.45%±1.60%)than at 15℃((30.54±0.81)mg g^(-1),9.09%±0.30%and 43.12%±1.65%)in the anhydrous transportation groups.In the watery transportation groups,a lower glycogen content,CI,and A.E.C.value were observed at 4℃((33.78±0.84)mg g^(-1),9.78%±0.50%and 64.65%±1.25%)than at 15℃((41.53±0.93)mg g^(-1),12.72%±0.83%and 71.58%±1.27%).Results from this study show that anhydrous transportation(4℃)is the optimal transport condition for clams to maintain a high quality and good physiological conditions.Thus,this study will be particularly useful for establishing shellfish transportation systems.展开更多
Preferably 20 ppm anhydrous ammonia (NH<sub>3</sub>) is proposed to be added to hydrogen fuel (H) made from renewable energy sources (green hydrogen), so that H leaks may be easily detectable by smell, but...Preferably 20 ppm anhydrous ammonia (NH<sub>3</sub>) is proposed to be added to hydrogen fuel (H) made from renewable energy sources (green hydrogen), so that H leaks may be easily detectable by smell, but not dangerously toxic. Including this odor agent, would allow H to be distributed safely in pipes, as required by law, and it would allow H to be safely stored, transported, and exported for sale, and widely commercialized. Further research is suggested to identify optimum pressure, temperature, and automated technique for injecting NH<sub>3</sub> into H, and to chart the minimum concentration needed, as a function of temperature and humidity. An application to make hypersonic H burning aircraft safer for ground maintenance crews is proposed. An ability to make, store and distribute H, made from local sources of renewable energy, would reduce a need for fossil fuels, especially in poor, remote communities, where it could improve their economy by creating an export product for sale, while reducing pollution.展开更多
Carbide slag was used as an activator to improve the activity of anhydrous phosphogypsum.Carbide slag could greatly improve the mechanical strength of anhydrous phosphogypsum than K_(2)SO_(4).The compressive strength ...Carbide slag was used as an activator to improve the activity of anhydrous phosphogypsum.Carbide slag could greatly improve the mechanical strength of anhydrous phosphogypsum than K_(2)SO_(4).The compressive strength of 11 wt%carbide slag and 1 wt%K_(2)SO_(4)activated anhydrous phosphogypsum increased greatly to 8.6 MPa at 3 d,and 11.9 MPa at 7 d,and 16.0 MPa at 28 d,respectively.The rate of hydration heat was accelerated and the total hydration heat was increased,and more calcium sulfate dihydrate was formed and cross-linked with other parts which improved the compressive strength of anhydrous phosphogypsum under the effects of different activators.It was indicated that carbide slag was a highly effective and cost-efficient activator.The result provides a highly effective and low-cost method which results in a novel and high value-added method for the utilization of phosphogypsum in the future.展开更多
A series of coesite,coexisting with or without a liquid phase,was synthesized in the nominal system SiO2-H2O at800-1450℃and 5 GPa.Micro-Raman spectroscopy was used to identity the crystalline phase,electron microprob...A series of coesite,coexisting with or without a liquid phase,was synthesized in the nominal system SiO2-H2O at800-1450℃and 5 GPa.Micro-Raman spectroscopy was used to identity the crystalline phase,electron microprobe and LA-ICP-MS were employed to quantity some major and trace elements,and unpolarized FTIR spectroscopy was applied to probe the different types of hydrogen defects,explore water-incorporation mechanisms and quantify water contents.Trace amounts of A1 and B were detected in the coesite.Combining our results with the results in the literatures,we have found no positive correlation between the Al contents and the"Al"-based hydrogen concentrations,suggesting that previously proposed hydrogen-incorporation mechanism H^++Al^3+■Si^4+does not function in coesite.In contrast,we have confirmed the positive correlation between the B contents and the B-based hydrogen concentrations.The hydrogen-incorporation mechanism H^++B3^+■Si^4+readily takes place in coesite at different P-T conditions,and significantly increases the water content at both liquid-saturated and liquid-undersaturated conditions.For the SiO2-H2O system,we have found that type-Ⅰhydrogarnet substitution plays a dictating role in incorporating water into coesite at liquid-saturated condition,type-II hydrogarnet substitution contributes significantly at nearly dry condition,and both operate at conditions in between.The water solubility of coesite,as dictated by the type-Ⅰhydrogarnet substitution,positively correlates with both P and T,cH2O=-105(30)+5.2(32)×P+0.112(26)×T,with cH2O in wt ppm,P in GPa and T in℃.Due to its low water solubility and small fraction in subducted slabs,coesite may contribute insignificantly to the vertical water transport in subduction zones.Furthermore,the water solubility of any coesite in exhuming ultra-high pressure metamorphic rocks should be virtually zero as coesite becomes metastable.With an adequately fast waterdiffusion rate,this metastable coesite should be completely dry,which may have been the key factor to the partial preservation of most natural Coe.As a byproduct,a new IR experimental protocol for accurate water determination in optically anisotropic nominally anhydrous minerals has been found.Aided with the empirical method of Paterson(1982)it employs multiple unpolarized IR spectra,collected from randomly-orientated mineral grains,to approximate both total integrated absorbance and total integrated molar absorption coefficient.Its success relies on a high-level orientation randomness in the IR analyses.展开更多
High-purity anhydrous magnesium chloride was prepared from magnesia and ammonium chloride.The chlorination process was analyzed and then the critical stages affecting the purity of anhydrous magnesium chloride were pi...High-purity anhydrous magnesium chloride was prepared from magnesia and ammonium chloride.The chlorination process was analyzed and then the critical stages affecting the purity of anhydrous magnesium chloride were pinpointed.The effect of sample dimension on the above critical stages was investigated respectively.The purity guarantee mechanism of anhydrous magnesium chloride was proposed.After that,magnesium metal was obtained via electrolyzing the anhydrous magnesium chloride-containing molten salt.The new process for the continuous production of magnesium metal from magnesia was proposed and discussed.The incomplete chlorination reaction and the hydrolysis of anhydrous magnesium chloride are the two critical stages affecting the purity of the anhydrous magnesium chloride.The dimension of the sample can influence reaction process and reaction mechanism,and thus the problems of incomplete chlorination reaction and hydrolysis can be solved together.The magnesia content in anhydrous magnesium chloride was below 0.1 wt.%when the ratio of height to diameter of the sample was over 2.43.The content of impurities in the magnesium metal obtained met the specifications of the product Mg9980.The current efficiency was(94.7±1.8)%and the electricity consumption was(9107±97)kW h/t.展开更多
Anhydrous lanthanide chlorides LnCl 3 (Ln=Sc, Y, La to Lu except for Pm), which are difficult to prepare in other ways, were prepared by chemical vapor transport (CVT) process. Rare earth oxide reacted with Al 2Cl ...Anhydrous lanthanide chlorides LnCl 3 (Ln=Sc, Y, La to Lu except for Pm), which are difficult to prepare in other ways, were prepared by chemical vapor transport (CVT) process. Rare earth oxide reacted with Al 2Cl 6 at 300℃ to produce LnCl 3, which was then separated from other solids by means of CVT at a temperature gradient from 400 to 180℃. Residual Al 2Cl 6 (g) was removed by carrier of dry N 2 gas at 200℃. The yielding rates were >90%, and the purity of products was >99.5%.展开更多
A simultaneous differential scanning calorimetryeFourier transform infrared(DSCeFTIR)microspectroscopy was used to quickly investigate the co-crystal formulation between anhydrous theophylline(TP)and anhydrous citric ...A simultaneous differential scanning calorimetryeFourier transform infrared(DSCeFTIR)microspectroscopy was used to quickly investigate the co-crystal formulation between anhydrous theophylline(TP)and anhydrous citric acid(CA)in a one-step procedure.The raw materials of TP andCA,aswell as the intactTPeCA co-crystal prepared by slow solvent evaporation were also respectively examined by this approach.The result indicates that the TPeCA cocrystal formulation was easily induced using this DSCeFTIR technique.The thermaldependent changes in three-dimensional FTIR spectral contour profiles were started from 165C to induce the co-crystal formation of TPeCA,which was prior to the endothermic peak at 173C found in the conventional DSC curve.Beyond 165C,several new IR absorption peaks at 3515,3124,1730,1710,1677,1648,1552 and 1265 cm1 corresponding to unique IR spectral peaks of intact TPeCA co-crystal were observed.The DSCeFTIR microspectroscopic results also evidenced the dimeremonomer transition of CA,but there were no markedly changes for TP or intact TPeCA co-crystal before its fusion.This strongly implies that the DSCeFTIR technique giving spectroscopic and thermodynamic information could simultaneously induce and identify the TPeCA co-crystal formation and phase transition of samples.Different storage conditions affecting the stability of both physical mixture and ground mixture of TPeCA were also determined.The physicalmixture of TPeCA after storing at 55C/75%RH condition for one day was fast transformed to TPeCA co-crystal,indicating that TPeCA co-crystal was easily induced under accelerated storage condition.While the co-crystal formed from TPeCA ground mixture was stable in both 25C/75%RH and 55C/75%RH conditions.展开更多
A static method was employed to study the reaction kinetics of anhydrous lithium hydroxide (LiOH) and CO2. The reaction generated water was absorbed with the composite silica gel of lanthanum chloride to make the expe...A static method was employed to study the reaction kinetics of anhydrous lithium hydroxide (LiOH) and CO2. The reaction generated water was absorbed with the composite silica gel of lanthanum chloride to make the experiment repeatable. At the reaction temperature of 15~60 ℃ and initial CO2 pressures of 25~100 kPa, the reaction rate of anhydrous LiOH and CO2 decreased slightly with the reduction of initial CO2 pressure and the rise of reaction temperature, indicating that the reaction activation energy of LiOH and CO2 was negative and close to zero. During the middle period (1~5 min) of the isothermal reaction, the ratio of reaction efficiency was approximately the power of 0.4 to that of initial CO2 pressures. As anhydrous LiOH reacted to CO2, the solid product Li2CO3 covered on the surface of LiOH was not compact, so it did not hinder the subsequent reaction of absorbing the CO2 gas. The reaction kinetics of anhydrous LiOH and CO2 obeyed the Erofeev′s model.展开更多
The anhydrous NdCl_a-LiNp (LiNp=Lithium uaphthalide) system has been fouud to cause a novel cyclodimerization of α, β-unsaturated ketoues to give cycio- -pentauol derivatives (1 and 2). A possible reaction mechanism...The anhydrous NdCl_a-LiNp (LiNp=Lithium uaphthalide) system has been fouud to cause a novel cyclodimerization of α, β-unsaturated ketoues to give cycio- -pentauol derivatives (1 and 2). A possible reaction mechanism was proposed.展开更多
The application state of anhydrous taphole clay in China and overseas was introduced. The characters and requirements of starting materials of anhydrous taphole clay. for blast furnace, and the formulation and propert...The application state of anhydrous taphole clay in China and overseas was introduced. The characters and requirements of starting materials of anhydrous taphole clay. for blast furnace, and the formulation and properties of anhydrous taphole clay in some plants were mentioned. The environment problems of anhydrous taphole clay were discussed and the developing trend was pointed out.展开更多
Highly active anhydrous potassium fluoride has many uses. Its good performance is demonstrated in high activity, high recovery, low consumption and the low emission of accessory substances during the process of organi...Highly active anhydrous potassium fluoride has many uses. Its good performance is demonstrated in high activity, high recovery, low consumption and the low emission of accessory substances during the process of organic fluorination. Moreover. there is no need to use an expensive intertransferable catalyst in the process of fluorination. Under the same conditions and within the same time limit, the fluorination rate of the product is 97% while that of ordinary anhydrous potassium fluoride is 58%. The product, developed recently by the Shenyang Chemical Research Institute, can remain in a state of superfine powder for a long time in air展开更多
This standard specifies the term, definition, brand, label, technical requirements, test methods, quality appraisal procedures, packing, marking, transportation, storage, and quality certificate of anhydrous taphole m...This standard specifies the term, definition, brand, label, technical requirements, test methods, quality appraisal procedures, packing, marking, transportation, storage, and quality certificate of anhydrous taphole mix for blast furnace.展开更多
In this study, the effect of substituting boron compounds with glycol-based grinding aids to the compressive strength performances of cement was investigated. Monoethylene glycol (MEG) and diethylene glycol (DEG) were...In this study, the effect of substituting boron compounds with glycol-based grinding aids to the compressive strength performances of cement was investigated. Monoethylene glycol (MEG) and diethylene glycol (DEG) were used as glycol-based grinding aids, and anhydrous borax and boric acid were used as boron compounds in the tests. CEM I type cement production was carried out with the addition of grinding aid mixtures to Portland clinker and some gypsum in the experiments. All produced cement samples were tested for Blaine fineness, xrf elemental analysis and 2, 7 and 28 days compressive strength tests. Test results of grinding aids of MEG and boron compounds mixture showed no increase in any age of compressive strengths performances related to MEG used itself. However, with the addition of boron compounds to DEG increased grinding aid performance at all ages (2, 7 and 28 days). Possible reasons for this increase could be borate esters formed with DEG and boric acid in a basic medium.展开更多
An easy preparation of tetrahydropyranyl (THP) ethers of alcohols and phenols with 3,4-dihydro-2H-pyran (DHP) in refluxing dichloromethane has been carried out in good to excellent yields under catalysis of anhydrous ...An easy preparation of tetrahydropyranyl (THP) ethers of alcohols and phenols with 3,4-dihydro-2H-pyran (DHP) in refluxing dichloromethane has been carried out in good to excellent yields under catalysis of anhydrous ferrous sulfate.展开更多
It is of great significance to develop high-temperature anhydrous proton conducting materials.Herein,we report a new strategy to significantly enhance the proton conductivity of covalent organic frameworks(COFs)throug...It is of great significance to develop high-temperature anhydrous proton conducting materials.Herein,we report a new strategy to significantly enhance the proton conductivity of covalent organic frameworks(COFs)through expanding the dimensionality of proton conduction.Three COF-based composites,COF-1@PA,COF-2@PA,and COF-3@PA(PA:phosphoric acid),are prepared by PA doping of three COFs with similar pore sizes but different amounts of hydrophilic groups.With the increase of hydrophilic groups,COFs can load more PA because of the enhanced hydrogen–bonding interactions between PA and the frameworks.powder X-ray diffraction(PXRD),scanning electron microscopy(SEM),and two-dimensional(2D)solid-state nuclear magnetic resonance(NMR)analyses show that PA can not only enter the channels of COF-3,but also insert into its 2D interlayers.This expands the proton conduction pathways from one-dimensional(1D)to three-dimensional(3D),which greatly improves the proton conductivity of COF-3.Meanwhile,the confinement effect of 1D channels and 2D layers of COF-3 also makes the hydrogen-bonded networks more orderly in COF-3@PA-30(30μL of PA loaded on COF-3).At 150℃,COF-3@PA-30 exhibits an ultrahigh anhydrous proton conductivity of 1.4 S·cm−1,which is a record of anhydrous proton conductivity reported to date.This work develops a new strategy for increasing the proton conductivity of 2D COF materials.展开更多
Background Alcohol has been used for treating simple renal cysts since 1981. Since then, various observational studies have examined the technique, but they differ significantly in the details of the procedures and ef...Background Alcohol has been used for treating simple renal cysts since 1981. Since then, various observational studies have examined the technique, but they differ significantly in the details of the procedures and efficacy measures used. This has made it difficult to assess the safety and efficacy of this technique. We carried out a randomized controlled trial to evaluate the efficacy and safety of ultrasound-guided alcohol sclerotherapy involving single-session multiple injections to treat simple renal cysts. Methods A total of 144 patients with simple renal cysts were randomly allocated to either the treatment group (ultrasound-guided percutaneous drainage and alcohol sclerotherapy with single-session multiple injections) or control group (ultrasound-guided simple percutaneous drainage). Follow-up CT scans of ablated cysts were collected 3 and 6 months after the procedure. The outcome was considered successful if cyst volume between baseline and 6 months decreased by at least 87.5%. Results Intention-to-treat analysis revealed an average volume reduction of 94.2% in the treatment group and 50.8% in the control group (P 〈0.0001). The percentage of patients achieving successful outcomes was 88.9% (95% CI 77.0%-100.0%) in the treatment group and 22.2% (95% CI 6.54%-37.9%) in the control group (P 〈0.0001). The corresponding results in the per-protocol analysis were an average volume reduction of 96.4% in the treatment group and 50.8% in the control group (P 〈0.0001). The percentage of patients achieving a successful outcome was 94,3% (95% CI 85.6%-100.0%) in the treatment group and 22.2% (95% CI 6.54%-37.9%) in the control group (P 〈0.0001 ). Conclusion Alcohol sclerotherapy involving single-session multiple injections is safe and efficacious in the treatment of renal cysts.展开更多
基金Funded by the National Natural Science Foundation of China (No. 50802019)
文摘Lime pretreated phosphogypsum(PG) was calcined at 500 ℃ to produce anhydrate gypsum cement. Due to the slow hydration of anhydrate gypsum, additives, K2SO4 and hemihydrate gypsum were selected to accelerate the hydration of anhydrate. The hydration characteristics, the resistance to hydrodynamic water, and the mineralogical studies were investigated. The experimental results suggest that activated by K2SO4 and hemihydrate, anhydrate PG hydrates much more rapidly than that in the presence of only K2SO4 or in the absence of additives. The binder has proper setting time, good strength development, and relatively better resistance to water. The hardened binder has hydrated products of rod or stick like shaped dihydrate gypsum crystals.
基金Funded by the National Natural Science Foundation of China(No.50802019)
文摘Phosphogypsum(PG) calcined at 500 ℃ was activated by K2SO4 and salt lime with loose structure as seed crystal. To determine the effect of activation, hydration of the anhydrate PG activated was investigated by examination of the setting time, the proportion of hydrated anhydrate PG, the microstructure of the hardenite and the resistance to water. Results show that activated anhydrate PG hydrates much more rapidly than that in the absence of activators. The activated anhydrate PG has proper setting time and hydrated proportion. The resistance to water was greatly improved. SEM photos show that the set activated PG has hydrated products of rod-like and closely connected crystals. The different addition of activator leads to different compact structure.
基金support provided by the National Natural Science Foundation of China (Project NO.50802019)the Introduction of Research Personnel Foundation of Guizhou University(Project No.2008019)
文摘In this work,phosphogypsum(PG) with a small amount of lime was thermally pretreated at 450 ℃ to produce anhydrate gypsum for the purpose of searching new ways for utilization of waste PG. Additives,K2SO4 and one selected seed crystal(SC),were used as activator for anhydrate PG. The hydration characteristics of the anhydrate PG binders were investigated by determination of the setting time,the ratio of hydrated anhydrate PG,the compressive strength development,and the microstructure of the hardenite. The resistance to water was studied by measuring mass loss of binders exposed to hydrodynamic water. Results suggest that activated by K2SO4 and SC,anhydrate PG hydrates much more rapidly than that without additives. The anhydrate PG binder with K2SO4 and SC has proper setting time and good strength developments. SEM photos show that the set binders have hydrated products of rodlike and regularly shaped crystals. Those crystals connected closely,and the hardenite has a compact structure,which is beneficial to the obtainment of good properties.
基金This study is supported by the National Key R&D Program of China(No.2018YFD0901004)the Innovation Team Project of Hebei Province Modern Agricultural Industry Technology System(No.HBCT2018170207)+1 种基金the Innovation Center of Hebei Agricultural Products Processing Technology(No.199676183H)the Modern Agricultural Industry Technology System(No.CARS-49).
文摘Given the increased circulation time after fishing,a series of changes take place in live clams,leading to a deterioration in quality even after death.Thus,in this study,we aimed to explore the optimal mode of transportation of clams.The container for holding clams was reformed,and a water circulation temperature control system was established.The physiological responses of clams during anhydrous and watery transportation at two temperatures(4 and 15℃)were investigated based on the aforementioned system.When comparing the transportation patterns after 3 d of transport,a higher survival rate was observed at 4℃(97%)than at 15℃(63%)in the anhydrous transportation groups and a lower survival rate was observed at 4℃(93%)than at 15℃(99%)in the watery transportation groups.In addition,the glycogen content,condition index(CI),and adenylate energy charge(A.E.C)value were higher at4℃((40.87±0.99)mg g^(-1),13.71%±0.50%and 57.45%±1.60%)than at 15℃((30.54±0.81)mg g^(-1),9.09%±0.30%and 43.12%±1.65%)in the anhydrous transportation groups.In the watery transportation groups,a lower glycogen content,CI,and A.E.C.value were observed at 4℃((33.78±0.84)mg g^(-1),9.78%±0.50%and 64.65%±1.25%)than at 15℃((41.53±0.93)mg g^(-1),12.72%±0.83%and 71.58%±1.27%).Results from this study show that anhydrous transportation(4℃)is the optimal transport condition for clams to maintain a high quality and good physiological conditions.Thus,this study will be particularly useful for establishing shellfish transportation systems.
文摘Preferably 20 ppm anhydrous ammonia (NH<sub>3</sub>) is proposed to be added to hydrogen fuel (H) made from renewable energy sources (green hydrogen), so that H leaks may be easily detectable by smell, but not dangerously toxic. Including this odor agent, would allow H to be distributed safely in pipes, as required by law, and it would allow H to be safely stored, transported, and exported for sale, and widely commercialized. Further research is suggested to identify optimum pressure, temperature, and automated technique for injecting NH<sub>3</sub> into H, and to chart the minimum concentration needed, as a function of temperature and humidity. An application to make hypersonic H burning aircraft safer for ground maintenance crews is proposed. An ability to make, store and distribute H, made from local sources of renewable energy, would reduce a need for fossil fuels, especially in poor, remote communities, where it could improve their economy by creating an export product for sale, while reducing pollution.
基金Funded by Innovation Group Fund Project of Hubei Province(No.2020CFA039)the Key Research and Development Program of Hubei Province(No.2020BCA077)。
文摘Carbide slag was used as an activator to improve the activity of anhydrous phosphogypsum.Carbide slag could greatly improve the mechanical strength of anhydrous phosphogypsum than K_(2)SO_(4).The compressive strength of 11 wt%carbide slag and 1 wt%K_(2)SO_(4)activated anhydrous phosphogypsum increased greatly to 8.6 MPa at 3 d,and 11.9 MPa at 7 d,and 16.0 MPa at 28 d,respectively.The rate of hydration heat was accelerated and the total hydration heat was increased,and more calcium sulfate dihydrate was formed and cross-linked with other parts which improved the compressive strength of anhydrous phosphogypsum under the effects of different activators.It was indicated that carbide slag was a highly effective and cost-efficient activator.The result provides a highly effective and low-cost method which results in a novel and high value-added method for the utilization of phosphogypsum in the future.
基金financially supported by the DREAM project of MOST,China(Grant No.2016YFC0600408)the Strategic Priority Research Program(B)of Chinese Academy of Sciences(Grant No.XDB18000000)the Program of the National Mineral Rock and Fossil Specimens Resource Center from MOST,China。
文摘A series of coesite,coexisting with or without a liquid phase,was synthesized in the nominal system SiO2-H2O at800-1450℃and 5 GPa.Micro-Raman spectroscopy was used to identity the crystalline phase,electron microprobe and LA-ICP-MS were employed to quantity some major and trace elements,and unpolarized FTIR spectroscopy was applied to probe the different types of hydrogen defects,explore water-incorporation mechanisms and quantify water contents.Trace amounts of A1 and B were detected in the coesite.Combining our results with the results in the literatures,we have found no positive correlation between the Al contents and the"Al"-based hydrogen concentrations,suggesting that previously proposed hydrogen-incorporation mechanism H^++Al^3+■Si^4+does not function in coesite.In contrast,we have confirmed the positive correlation between the B contents and the B-based hydrogen concentrations.The hydrogen-incorporation mechanism H^++B3^+■Si^4+readily takes place in coesite at different P-T conditions,and significantly increases the water content at both liquid-saturated and liquid-undersaturated conditions.For the SiO2-H2O system,we have found that type-Ⅰhydrogarnet substitution plays a dictating role in incorporating water into coesite at liquid-saturated condition,type-II hydrogarnet substitution contributes significantly at nearly dry condition,and both operate at conditions in between.The water solubility of coesite,as dictated by the type-Ⅰhydrogarnet substitution,positively correlates with both P and T,cH2O=-105(30)+5.2(32)×P+0.112(26)×T,with cH2O in wt ppm,P in GPa and T in℃.Due to its low water solubility and small fraction in subducted slabs,coesite may contribute insignificantly to the vertical water transport in subduction zones.Furthermore,the water solubility of any coesite in exhuming ultra-high pressure metamorphic rocks should be virtually zero as coesite becomes metastable.With an adequately fast waterdiffusion rate,this metastable coesite should be completely dry,which may have been the key factor to the partial preservation of most natural Coe.As a byproduct,a new IR experimental protocol for accurate water determination in optically anisotropic nominally anhydrous minerals has been found.Aided with the empirical method of Paterson(1982)it employs multiple unpolarized IR spectra,collected from randomly-orientated mineral grains,to approximate both total integrated absorbance and total integrated molar absorption coefficient.Its success relies on a high-level orientation randomness in the IR analyses.
基金supported by the National Natural Science Foundation of China(51501178)Autonomous Research Fund of State Key Laboratory of Multiphase Complex Systems(MPCS-2019-A-10)。
文摘High-purity anhydrous magnesium chloride was prepared from magnesia and ammonium chloride.The chlorination process was analyzed and then the critical stages affecting the purity of anhydrous magnesium chloride were pinpointed.The effect of sample dimension on the above critical stages was investigated respectively.The purity guarantee mechanism of anhydrous magnesium chloride was proposed.After that,magnesium metal was obtained via electrolyzing the anhydrous magnesium chloride-containing molten salt.The new process for the continuous production of magnesium metal from magnesia was proposed and discussed.The incomplete chlorination reaction and the hydrolysis of anhydrous magnesium chloride are the two critical stages affecting the purity of the anhydrous magnesium chloride.The dimension of the sample can influence reaction process and reaction mechanism,and thus the problems of incomplete chlorination reaction and hydrolysis can be solved together.The magnesia content in anhydrous magnesium chloride was below 0.1 wt.%when the ratio of height to diameter of the sample was over 2.43.The content of impurities in the magnesium metal obtained met the specifications of the product Mg9980.The current efficiency was(94.7±1.8)%and the electricity consumption was(9107±97)kW h/t.
文摘Anhydrous lanthanide chlorides LnCl 3 (Ln=Sc, Y, La to Lu except for Pm), which are difficult to prepare in other ways, were prepared by chemical vapor transport (CVT) process. Rare earth oxide reacted with Al 2Cl 6 at 300℃ to produce LnCl 3, which was then separated from other solids by means of CVT at a temperature gradient from 400 to 180℃. Residual Al 2Cl 6 (g) was removed by carrier of dry N 2 gas at 200℃. The yielding rates were >90%, and the purity of products was >99.5%.
基金This work was supported by National Science Council,Taipei,Taiwan(NSC 100-2320-B-264-001-MY3).
文摘A simultaneous differential scanning calorimetryeFourier transform infrared(DSCeFTIR)microspectroscopy was used to quickly investigate the co-crystal formulation between anhydrous theophylline(TP)and anhydrous citric acid(CA)in a one-step procedure.The raw materials of TP andCA,aswell as the intactTPeCA co-crystal prepared by slow solvent evaporation were also respectively examined by this approach.The result indicates that the TPeCA cocrystal formulation was easily induced using this DSCeFTIR technique.The thermaldependent changes in three-dimensional FTIR spectral contour profiles were started from 165C to induce the co-crystal formation of TPeCA,which was prior to the endothermic peak at 173C found in the conventional DSC curve.Beyond 165C,several new IR absorption peaks at 3515,3124,1730,1710,1677,1648,1552 and 1265 cm1 corresponding to unique IR spectral peaks of intact TPeCA co-crystal were observed.The DSCeFTIR microspectroscopic results also evidenced the dimeremonomer transition of CA,but there were no markedly changes for TP or intact TPeCA co-crystal before its fusion.This strongly implies that the DSCeFTIR technique giving spectroscopic and thermodynamic information could simultaneously induce and identify the TPeCA co-crystal formation and phase transition of samples.Different storage conditions affecting the stability of both physical mixture and ground mixture of TPeCA were also determined.The physicalmixture of TPeCA after storing at 55C/75%RH condition for one day was fast transformed to TPeCA co-crystal,indicating that TPeCA co-crystal was easily induced under accelerated storage condition.While the co-crystal formed from TPeCA ground mixture was stable in both 25C/75%RH and 55C/75%RH conditions.
基金Project supported bythe Beijing Education Committee Scientific Plan Fund (KM200711417006)
文摘A static method was employed to study the reaction kinetics of anhydrous lithium hydroxide (LiOH) and CO2. The reaction generated water was absorbed with the composite silica gel of lanthanum chloride to make the experiment repeatable. At the reaction temperature of 15~60 ℃ and initial CO2 pressures of 25~100 kPa, the reaction rate of anhydrous LiOH and CO2 decreased slightly with the reduction of initial CO2 pressure and the rise of reaction temperature, indicating that the reaction activation energy of LiOH and CO2 was negative and close to zero. During the middle period (1~5 min) of the isothermal reaction, the ratio of reaction efficiency was approximately the power of 0.4 to that of initial CO2 pressures. As anhydrous LiOH reacted to CO2, the solid product Li2CO3 covered on the surface of LiOH was not compact, so it did not hinder the subsequent reaction of absorbing the CO2 gas. The reaction kinetics of anhydrous LiOH and CO2 obeyed the Erofeev′s model.
基金Project supported by the National Science Foundation of China
文摘The anhydrous NdCl_a-LiNp (LiNp=Lithium uaphthalide) system has been fouud to cause a novel cyclodimerization of α, β-unsaturated ketoues to give cycio- -pentauol derivatives (1 and 2). A possible reaction mechanism was proposed.
文摘The application state of anhydrous taphole clay in China and overseas was introduced. The characters and requirements of starting materials of anhydrous taphole clay. for blast furnace, and the formulation and properties of anhydrous taphole clay in some plants were mentioned. The environment problems of anhydrous taphole clay were discussed and the developing trend was pointed out.
文摘Highly active anhydrous potassium fluoride has many uses. Its good performance is demonstrated in high activity, high recovery, low consumption and the low emission of accessory substances during the process of organic fluorination. Moreover. there is no need to use an expensive intertransferable catalyst in the process of fluorination. Under the same conditions and within the same time limit, the fluorination rate of the product is 97% while that of ordinary anhydrous potassium fluoride is 58%. The product, developed recently by the Shenyang Chemical Research Institute, can remain in a state of superfine powder for a long time in air
文摘This standard specifies the term, definition, brand, label, technical requirements, test methods, quality appraisal procedures, packing, marking, transportation, storage, and quality certificate of anhydrous taphole mix for blast furnace.
基金Funds by Murat Calli (Ph.D. Student in the Department of Chemical Engineeringin Selcuk University and Quality Manager in SYCS Construction and CementCompany)
文摘In this study, the effect of substituting boron compounds with glycol-based grinding aids to the compressive strength performances of cement was investigated. Monoethylene glycol (MEG) and diethylene glycol (DEG) were used as glycol-based grinding aids, and anhydrous borax and boric acid were used as boron compounds in the tests. CEM I type cement production was carried out with the addition of grinding aid mixtures to Portland clinker and some gypsum in the experiments. All produced cement samples were tested for Blaine fineness, xrf elemental analysis and 2, 7 and 28 days compressive strength tests. Test results of grinding aids of MEG and boron compounds mixture showed no increase in any age of compressive strengths performances related to MEG used itself. However, with the addition of boron compounds to DEG increased grinding aid performance at all ages (2, 7 and 28 days). Possible reasons for this increase could be borate esters formed with DEG and boric acid in a basic medium.
文摘An easy preparation of tetrahydropyranyl (THP) ethers of alcohols and phenols with 3,4-dihydro-2H-pyran (DHP) in refluxing dichloromethane has been carried out in good to excellent yields under catalysis of anhydrous ferrous sulfate.
基金We are grateful for financial support from the National Natural Science Foundation of China(Nos.21771193 and 22275210)Key Research and Development Projects of Shandong Province(No.2019JZZY010331).
文摘It is of great significance to develop high-temperature anhydrous proton conducting materials.Herein,we report a new strategy to significantly enhance the proton conductivity of covalent organic frameworks(COFs)through expanding the dimensionality of proton conduction.Three COF-based composites,COF-1@PA,COF-2@PA,and COF-3@PA(PA:phosphoric acid),are prepared by PA doping of three COFs with similar pore sizes but different amounts of hydrophilic groups.With the increase of hydrophilic groups,COFs can load more PA because of the enhanced hydrogen–bonding interactions between PA and the frameworks.powder X-ray diffraction(PXRD),scanning electron microscopy(SEM),and two-dimensional(2D)solid-state nuclear magnetic resonance(NMR)analyses show that PA can not only enter the channels of COF-3,but also insert into its 2D interlayers.This expands the proton conduction pathways from one-dimensional(1D)to three-dimensional(3D),which greatly improves the proton conductivity of COF-3.Meanwhile,the confinement effect of 1D channels and 2D layers of COF-3 also makes the hydrogen-bonded networks more orderly in COF-3@PA-30(30μL of PA loaded on COF-3).At 150℃,COF-3@PA-30 exhibits an ultrahigh anhydrous proton conductivity of 1.4 S·cm−1,which is a record of anhydrous proton conductivity reported to date.This work develops a new strategy for increasing the proton conductivity of 2D COF materials.
文摘Background Alcohol has been used for treating simple renal cysts since 1981. Since then, various observational studies have examined the technique, but they differ significantly in the details of the procedures and efficacy measures used. This has made it difficult to assess the safety and efficacy of this technique. We carried out a randomized controlled trial to evaluate the efficacy and safety of ultrasound-guided alcohol sclerotherapy involving single-session multiple injections to treat simple renal cysts. Methods A total of 144 patients with simple renal cysts were randomly allocated to either the treatment group (ultrasound-guided percutaneous drainage and alcohol sclerotherapy with single-session multiple injections) or control group (ultrasound-guided simple percutaneous drainage). Follow-up CT scans of ablated cysts were collected 3 and 6 months after the procedure. The outcome was considered successful if cyst volume between baseline and 6 months decreased by at least 87.5%. Results Intention-to-treat analysis revealed an average volume reduction of 94.2% in the treatment group and 50.8% in the control group (P 〈0.0001). The percentage of patients achieving successful outcomes was 88.9% (95% CI 77.0%-100.0%) in the treatment group and 22.2% (95% CI 6.54%-37.9%) in the control group (P 〈0.0001). The corresponding results in the per-protocol analysis were an average volume reduction of 96.4% in the treatment group and 50.8% in the control group (P 〈0.0001). The percentage of patients achieving a successful outcome was 94,3% (95% CI 85.6%-100.0%) in the treatment group and 22.2% (95% CI 6.54%-37.9%) in the control group (P 〈0.0001 ). Conclusion Alcohol sclerotherapy involving single-session multiple injections is safe and efficacious in the treatment of renal cysts.