Room temperature sputtered inorganic nickel oxide(NiO_(x))is one of the most promising hole transport layers(HTL)for perovskite-sillion 2-terminal tandem solar cells with the aid of ultrathin and compact organic layer...Room temperature sputtered inorganic nickel oxide(NiO_(x))is one of the most promising hole transport layers(HTL)for perovskite-sillion 2-terminal tandem solar cells with the aid of ultrathin and compact organic layers to passivate the surface defects.In this study,the aromatic solvent with different substituent groups was used to regulate the conformation of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)am ine](PTAA)layer.As a result,the single-junction perovskite solar cell(PSC)gained a power conversion efficiency(PCE)of 20.63%,contributing to a 27.21%efficiency for monolithic perovskite/silicon(double-side polished)2-terminal tandem solar cell,by applying the alkyl aromatic solvent to enhance theπ-πstacking of PTAA molecular chains.The tandem solar cell can maintain 95%initial efficiency after aging over 1000 h.This study provides a universal approach for improving the photovoltaic performance of NiO_(x)/polymer-based perovskite/silicon tandem solar cells and other single junction inverted PSCs.展开更多
This paper reports that the blend films of poly (2-methoxy-5-(2'-ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV) and N,N'-bis(1-ethylpropyl)-3,4: 9,10-perylene bis (tetracarboxyl diimide) (EP-PDI) with ...This paper reports that the blend films of poly (2-methoxy-5-(2'-ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV) and N,N'-bis(1-ethylpropyl)-3,4: 9,10-perylene bis (tetracarboxyl diimide) (EP-PDI) with the weight ratio of 1:2.5 have been prepared by spin-coating from chloroform (CF) and chlorobenzene (CB) solutions respectively. The absorption spectra and the morphology of the blend films show that large crystal-like EP-PDI aggregates are formed in film prepared from CB solution, which corresponds to a new absorption shoulder near 590 nm, while there is no shoulder around 590 nm in the UV-Vis absorption spectra of the blend film from CF solution. The electric-field dependence spectra of the photocurrent generation quantum yield of the film from CB solution shows that at weak electric field the EP-PDI aggregates act as more efficient sensitizers, but at strong electric field the quantum yields become almost invariable over the entire spectral range no matter what the state of EP-PDI, monomer or aggregate. At strong electric field, the photocurrent generation yields of both films from CF and CB solution saturate and their yield spectra become spectrally similar, mentioning that at strong electric field the photoexcitons dissociate efficiently and the free charges are collected by the electrodes almost completely.展开更多
The interaction of a relativistic electron beam (REB) with inhomogeneous, magneto-active, relativistic warm plasma is theoretically investigated. The nonlinear formation of waves at second and triple frequency at the ...The interaction of a relativistic electron beam (REB) with inhomogeneous, magneto-active, relativistic warm plasma is theoretically investigated. The nonlinear formation of waves at second and triple frequency at the inlet of the beam into the plasma is investigated. Effects of external static or oscillating magnetic field are considered. Nonlinear effects associated with the generation of second and triple harmonics, play an important role in the process of energy transfer from the beam to the plasma as compared with linear stage.展开更多
Microbial fuel cells(MFCs)employing Pseudomonas putida B6-2(ATCC BAA-2545)as an exoelectrogen have been developed to harness energy from various conventional substrates,such as acetate,lactate,glucose,and fructose.Owi...Microbial fuel cells(MFCs)employing Pseudomonas putida B6-2(ATCC BAA-2545)as an exoelectrogen have been developed to harness energy from various conventional substrates,such as acetate,lactate,glucose,and fructose.Owing to its metabolic versatility,P.putida B6-2 demonstrates adaptable growth rates on diverse,cost-effective carbon sources within MFCs,exhibiting distinct energy production characteristics.Notably,the anode chamber’s pH rises with carboxylates’(acetate and lactate)consumption and decreases with carbohydrates’(glucose and fructose)utilization.The MFC utilizing fructose as a substrate achieved the highest power density at 411 mW m^(−2).Initial analysis revealed that P.putida B6-2 forms biofilms covered with nanowires,contributing to bioelectricity generation.These microbial nanowires are likely key players in direct extracellular electron transport through physical contact.This study established a robust foundation for producing valuable compounds and bioenergy from common substrates in bioelectrochemical systems(BESs)utilizing P.putida as an exoelectrogen.展开更多
Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent,...Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent, volume ratio of water phase to organic phase, pH value of aqueous phase and reaction temperature on the initial reaction rate, maximum yield and enantiomeric excess (ee) of the product were systematically explored. All the above-mentioned factors had significant influence on the reaction. n-Hexane was found to be the best organic solvent for the reaction. The optimum shake speed, volume ratio of water phase to organic phase, pH value and reaction temperature were 150 r.min-1, 1/2, 8 and 30 ℃ respectively, under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%, which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase. To our best knowledge, this is the most satisfactory result obtained.展开更多
Extraction of copper and ammonia from Cu2+-NH3-Cl--H2O solution using laboratorialy synthesized sterically hindered β-diketone(4,4-dimethyl-1-(4-dodecylphenyl)-1,3-pentanedione) was studied.The effects of the copper ...Extraction of copper and ammonia from Cu2+-NH3-Cl--H2O solution using laboratorialy synthesized sterically hindered β-diketone(4,4-dimethyl-1-(4-dodecylphenyl)-1,3-pentanedione) was studied.The effects of the copper concentration,the total ammonia concentration,the initial pH in the aqueous phase,the phase ratio,and the temperature on copper extraction ratio and ammonia extraction in loaded organic phase were investigated using this sterically hindered β-diketone.Under the conditions of temperature 25℃,contact time of two phases 30 min,phase ratio 1-1,concentration of copper 3 g/L,concentration of total ammonia 3 mol/L,aqueous pH 8.43,and the concentration of β-diketone in organic phase 20%(volume fraction),ammonia in aqueous phase is much lower to be extracted by organic phase(just 14.5 mg/L),while the extraction rate of copper is 95.09%.展开更多
The poor dissolution characteristics of water-insoluble drugs are a major challenge for pharmaceutical scientists.Reduction of the particle size/increase in the surface area of the drug is a widely used and relatively...The poor dissolution characteristics of water-insoluble drugs are a major challenge for pharmaceutical scientists.Reduction of the particle size/increase in the surface area of the drug is a widely used and relatively simple method for increasing dissolution rates.The objective of this study was to improve solubility,release and comparability of dissolution of a poorly soluble drug using two different types of formulations(solid dispersions and microspheres).Hydrochlorothiazide was used as a model drug.The solid dispersions and microspheres were prepared by solvent evaporation method using ethyl cellulose,hydroxypropyl methylcellulose in different drug-to-carrier ratios(1:1,1:2 w:w).The prepared formulations were evaluated for interaction study by Fourier transform infrared spectroscopy,differential scanning calorimetry,percentage of practical yield,drug loading,surface morphology by scanning electron microscopy,optical microscopy and in-vitro release studies.The results showed no interaction between the drug and polymer,amorphous state of solid dispersions and microspheres,percentage yield of 42.53%to 78.10%,drug content of 99.60%to 99.64%,good spherical appearance in formulation VI and significant increase in the dissolution rate.展开更多
In this paper, fibrillation properties of solvent - spun cellulose fiber and some influencing factors are analyzed based on the experiment results. It is pointed out that special textile styles and aesthetic appearanc...In this paper, fibrillation properties of solvent - spun cellulose fiber and some influencing factors are analyzed based on the experiment results. It is pointed out that special textile styles and aesthetic appearance could be obtained by controlling the fibrillation.展开更多
This work investigated the separation of potassium from sodium in alkaline solution using substituted phenol-based extractants.Superior potassium extraction was achieved with 4-tert-butyl-2-(α-methylbenzyl)phenol(t-B...This work investigated the separation of potassium from sodium in alkaline solution using substituted phenol-based extractants.Superior potassium extraction was achieved with 4-tert-butyl-2-(α-methylbenzyl)phenol(t-BAMBP)than 4-sec-butyl-2-(α-methylbenzyl)phenol(BAMBP).The optimum conditions for the extraction were 1 mol/L t-BAMBP,3:1 volumetric phase ratio(O/A),and two extraction stages.After cross-current extraction,the extraction ratio of potassium reached 90.8%.After scrubbing with deionised water at phase ratio of 4:1 and scrubbing stage of 4,a sodium scrubbing efficiency of 88.2%was obtained.After stripping using 1 mol/L H_(2)SO_(4) at phase ratio of 3:1,the stripping efficiency of potassium reached 94.2%.The potassium/sodium(K/Na)concentration ratio increased 14.3 times from 0.15 in the feed solution to 2.3 in the stripping solution.The efficient separation of potassium from sodium in alkaline solution was achieved via solvent extraction with t-BAMBP.展开更多
The characteristics and research methods of terrigenous organic hydrocarbon-generated source rock in coal measures are studied in this thesis. After abundance of organic matters, pyrolysis parameter of rocks and hydro...The characteristics and research methods of terrigenous organic hydrocarbon-generated source rock in coal measures are studied in this thesis. After abundance of organic matters, pyrolysis parameter of rocks and hydrocarbon generated capacity of macerals are basically discussed in coal measures of the Cretaceous Muleng-Chengzihe formation in Suibin depression in Sanjang basin, the hydrocarbon generated grade in coal-genera^ted source rock is ascertained in this depression. At last, we think that it is a main attack prospect in coal-genera^ted hydrocarbons study in the future to research the macerals of coal measures organic source rock and to build a criterion to classify the coal-generated hydrocarbons in Northeast region.展开更多
Wax esters were synthesized in a solvent free system catalyzed by immobilized lipase from Candida sp. 99-125, with oleic acid and cetyl alcohol. The effects of substrate molar ratio, lipase dosage and water removal we...Wax esters were synthesized in a solvent free system catalyzed by immobilized lipase from Candida sp. 99-125, with oleic acid and cetyl alcohol. The effects of substrate molar ratio, lipase dosage and water removal were investigated in a 50 ml flask incubated in a thermostatic cultivation cabinet. The optimized conditions were: temperature 40 ℃, shaking at 170 r·min-1, acid/alcohol molar ratio 1:0.9, lipase dosage in 10% (by mass) of oleic acid, and open reaction for water removal. As a result, the conversion rate reached 98% for reaction of 8 h. The volume of reactor was scaled up to 1 L three-neck flask. The optimized parameters were: 200 r·min-1 agitation speed, 2.5% (by mass) lipase dosage, others were the same as the parameters described above. The conversion rate reached 95% for reaction of 24 h. The lipase retained 46% conversion rate after reuse for 6, 7 batches. The products were purified by removing remained cetyl alcohol and fatty acids with ethanol and saturated sodium carbonate so-lution, respectively. The purity of the wax ester, cetyl oleate, was 96%. The physical and chemical properties of cetyl oleate were tested and compared with those of jojoba oil. The results show that the product cetyl oleate has great potential to use as the substitute of natural jojoba oil.展开更多
Electronic structures and absorption spectra properties of complex 8-((trimethoxysilyl)methylthio)quinoline.SnCh in gas phase and MeCN media have been investigated by using DFT/TD-DFT method. The calculated lowest...Electronic structures and absorption spectra properties of complex 8-((trimethoxysilyl)methylthio)quinoline.SnCh in gas phase and MeCN media have been investigated by using DFT/TD-DFT method. The calculated lowest-energy absorption band shows different mechanisms under these two conditions, and it bears LMCT/LLCT/ILCT character in MeCN solution and LLCT/ILCT character in gas phase. The calculated absorption bands of the title complex in MeCN solvent are in good agreement with the experimental results, and calculation results indicate that the very weak experimentally observed lowest-energy absorption band of the title complex in MeCN solvent originates from the spin-forbidden singlet-triplet transitions.展开更多
The Bohai Bay Basin is a typical oil-prone basin, in which natural gas geological reserves have a small proportion. In this basin, the gas source rock is largely medium-deep lake mudstone with oil-prone type Ⅱ2-Ⅱ1 k...The Bohai Bay Basin is a typical oil-prone basin, in which natural gas geological reserves have a small proportion. In this basin, the gas source rock is largely medium-deep lake mudstone with oil-prone type Ⅱ2-Ⅱ1 kerogens, and natural gas preservation conditions are poor due to active late tectonic movements. The formation conditions of large natural gas fields in the Bohai Bay Basin have been elusive. Based on the exploration results of Bohai Bay Basin and comparison with large gas fields in China and abroad, the formation conditions of conventional large-scale natural gas reservoirs in the Bohai Bay Basin were examined from accumulation dynamics, structure and sedimentation. The results show that the formation conditions of conventional large natural gas reservoirs in Bohai Bay Basin mainly include one core element and two key elements. The core factor is the strong sealing of Paleogene "quilt-like" overpressure mudstone. The two key factors include the rapid maturation and high-intensity gas generation of source rock in the late stage and large scale reservoir. On this basis, large-scale nature gas accumulation models in the Bohai Bay Basin have been worked out, including regional overpressure mudstone enriching model, local overpressure mudstone depleting model, sand-rich sedimentary subsag depleting model and late strongly-developed fault depleting model. It is found that Bozhong sag, northern Liaozhong sag and Banqiao sag have favorable conditions for the formation of large-scale natural gas reservoirs, and are worth exploring. The study results have important guidance for exploration of large scale natural gas reservoirs in the Bohai Bay Basin.展开更多
In order to clarify the mechanism and the complex formed in the extraction of divalent Mn by alkylphosphonic acid monoester, the solid complex has been prepared by mono (2-ethylhexyl)-2-ethylhexyl phosphate, HEH(EH)P,...In order to clarify the mechanism and the complex formed in the extraction of divalent Mn by alkylphosphonic acid monoester, the solid complex has been prepared by mono (2-ethylhexyl)-2-ethylhexyl phosphate, HEH(EH)P, HA with divalent Mn. The elemental analysis, magnetic susceptibility and thermogravimetry have been determined for the solid complex of HEH(EH)P-Mn(II) and the infrared spectrum has been carried out in comparison to the extractant HEH(EH)P. The extracted compound has also been studied by electronic and electron spin resonance spectroscopy in octane solvent and solid state at room temperature. On the basis of the measurements, it is concluded that the structure of the solid polymeric species MnA_2 is in a tetrahedral arrangement.展开更多
ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these material...ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these materials have acquired renewed importance due to the new explored nanolayer properties of modern devices. In addition, as shown in this work they can be grown using uncomplicated synthesis techniques based on the deposition in vapour phase of the elemental precursors. This work presents the results obtained from the deposition of nanolayers of these materials using the precursor vapour on GaAs and GaSb (001) substrates. This growth technique, extensively known as atomic layer deposition (ALD), allows the layers growth with nanometric dimension. The main results presented in this work are the used growth parameters and the results of the structural characterization of the layers by the means of Raman spectroscopy measurements. Raman scattering shows the peak corresponding to longitudinal optical (LO)-ZnTe, which is weak and slightly redshift in comparison with that reported for the ZnTe bulk at 210 cm^-1. For the case of the CdTe nanolayer, Raman spectra presented the LO-CdTe peak, which is indicative of the successful growth of the layer. Its weak and slightly redshift in comparison with that reported for the CdTe bulk can be related with the nanometric characteristic of this layer. The performed high-resolution X-ray diffraction (HR-XRD) measurement allows to study some important characteristics such as the crystallinity of the grown layer. In addition, the HR-XRD measurement suggests that the crystalline quality has dependence on the growth temperature.展开更多
The growth of crystals of the high T c oxide superconductors has been hampe red by the complexities of the materials and their phase diagrams.The most common crys tal growth technique adopted for these oxides is the ...The growth of crystals of the high T c oxide superconductors has been hampe red by the complexities of the materials and their phase diagrams.The most common crys tal growth technique adopted for these oxides is the “flux”method,where the st arting materials are solved in a melt,which is usually formed by excess CuO and BaO or a KCl/NaCl mixture.The crystals are produced by slow cooling of the heate d solvent.This method,however,suffers from several disadvantages: (1) the crystals are contaminated with the crucible material, (2) the crystals are difficult to remove from the crucible, (3) the crystals contain flux inclusions.展开更多
Anri-idiotypic monoclonal antibody (Mab Ab2 ) by MAb COC166-9 against ovarian serous papillary adenocarcinoma was prepared. Hybridomas of Ab2 screened by sandwich ELISA and immunocompetitive inhibition tests were proc...Anri-idiotypic monoclonal antibody (Mab Ab2 ) by MAb COC166-9 against ovarian serous papillary adenocarcinoma was prepared. Hybridomas of Ab2 screened by sandwich ELISA and immunocompetitive inhibition tests were procured and named as 6B11 and 1H12. The number of their chromosomes were 93 and 91, and DNA analysis also proved the characteristics of hybridomas. These Ab2s could induce delayed type hypersensitivity (DTH), the cellular immune response. The results of the immune reaction of 6B11 with SKOV3 (ovarian carcinoma cell line) were similar to OC166-9 (Ag), the positive control, while 1H12 was weaker. Anti-and-idiotypic antibody (Ab3) was also raised by 6B11 and 1H12 respectively. They all showed positive immunohistochemical stainings with ovarian serous adenocarcinoma tissue sections and immunocytochemical stainings with SKOV3 cells as was shown by COC166-9. In the antibody dependent cell mediated cytotoxicity (ADCC) tests, they showed no differences against SKOV3 as compared with COC166-9. We anticipate that 6B11 and 1H12 may be used as vaccines against ovarian carcinoma and may provide a clue for its prevention and treatment.展开更多
基金supported by the National Key R&D Program of China(2018YFB1500103)the National Natural Science Foundation of China(62104082)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(2022A1515010746,2022A1515011228)the Science and Technology Program of Guangzhou(202201010458)。
文摘Room temperature sputtered inorganic nickel oxide(NiO_(x))is one of the most promising hole transport layers(HTL)for perovskite-sillion 2-terminal tandem solar cells with the aid of ultrathin and compact organic layers to passivate the surface defects.In this study,the aromatic solvent with different substituent groups was used to regulate the conformation of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)am ine](PTAA)layer.As a result,the single-junction perovskite solar cell(PSC)gained a power conversion efficiency(PCE)of 20.63%,contributing to a 27.21%efficiency for monolithic perovskite/silicon(double-side polished)2-terminal tandem solar cell,by applying the alkyl aromatic solvent to enhance theπ-πstacking of PTAA molecular chains.The tandem solar cell can maintain 95%initial efficiency after aging over 1000 h.This study provides a universal approach for improving the photovoltaic performance of NiO_(x)/polymer-based perovskite/silicon tandem solar cells and other single junction inverted PSCs.
基金Project supported by the State Key Development Program for Basic Research of China (Grant No 2002CB613401), the National Natural Science Foundation of China (Grant Nos 20474023 and 50673035), the Program for Changjiang Scholars and Innovative Research Team in University (Grant No IRT0422), the 111 Project (Grant No B06009) and the Research Project of Jilin Province, China (Grant Nos 20050504 and 20060702).
文摘This paper reports that the blend films of poly (2-methoxy-5-(2'-ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV) and N,N'-bis(1-ethylpropyl)-3,4: 9,10-perylene bis (tetracarboxyl diimide) (EP-PDI) with the weight ratio of 1:2.5 have been prepared by spin-coating from chloroform (CF) and chlorobenzene (CB) solutions respectively. The absorption spectra and the morphology of the blend films show that large crystal-like EP-PDI aggregates are formed in film prepared from CB solution, which corresponds to a new absorption shoulder near 590 nm, while there is no shoulder around 590 nm in the UV-Vis absorption spectra of the blend film from CF solution. The electric-field dependence spectra of the photocurrent generation quantum yield of the film from CB solution shows that at weak electric field the EP-PDI aggregates act as more efficient sensitizers, but at strong electric field the quantum yields become almost invariable over the entire spectral range no matter what the state of EP-PDI, monomer or aggregate. At strong electric field, the photocurrent generation yields of both films from CF and CB solution saturate and their yield spectra become spectrally similar, mentioning that at strong electric field the photoexcitons dissociate efficiently and the free charges are collected by the electrodes almost completely.
文摘The interaction of a relativistic electron beam (REB) with inhomogeneous, magneto-active, relativistic warm plasma is theoretically investigated. The nonlinear formation of waves at second and triple frequency at the inlet of the beam into the plasma is investigated. Effects of external static or oscillating magnetic field are considered. Nonlinear effects associated with the generation of second and triple harmonics, play an important role in the process of energy transfer from the beam to the plasma as compared with linear stage.
基金supported by grants from National Natural Science Foundation of China (32070097 and 91951202)National Key Research and Development Program of China (2019YFA0904800).
文摘Microbial fuel cells(MFCs)employing Pseudomonas putida B6-2(ATCC BAA-2545)as an exoelectrogen have been developed to harness energy from various conventional substrates,such as acetate,lactate,glucose,and fructose.Owing to its metabolic versatility,P.putida B6-2 demonstrates adaptable growth rates on diverse,cost-effective carbon sources within MFCs,exhibiting distinct energy production characteristics.Notably,the anode chamber’s pH rises with carboxylates’(acetate and lactate)consumption and decreases with carbohydrates’(glucose and fructose)utilization.The MFC utilizing fructose as a substrate achieved the highest power density at 411 mW m^(−2).Initial analysis revealed that P.putida B6-2 forms biofilms covered with nanowires,contributing to bioelectricity generation.These microbial nanowires are likely key players in direct extracellular electron transport through physical contact.This study established a robust foundation for producing valuable compounds and bioenergy from common substrates in bioelectrochemical systems(BESs)utilizing P.putida as an exoelectrogen.
基金Supported by the National Natural Science Foundation of China(No.20076019)the Natural Science Foundation of Guang-dong Province(No.000444).
文摘Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent, volume ratio of water phase to organic phase, pH value of aqueous phase and reaction temperature on the initial reaction rate, maximum yield and enantiomeric excess (ee) of the product were systematically explored. All the above-mentioned factors had significant influence on the reaction. n-Hexane was found to be the best organic solvent for the reaction. The optimum shake speed, volume ratio of water phase to organic phase, pH value and reaction temperature were 150 r.min-1, 1/2, 8 and 30 ℃ respectively, under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%, which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase. To our best knowledge, this is the most satisfactory result obtained.
基金Project(2007CB613601) supported by the National Basic Research Program of ChinaProject(NCET-08) supported by Program for New Century Excellent Talents in University, China
文摘Extraction of copper and ammonia from Cu2+-NH3-Cl--H2O solution using laboratorialy synthesized sterically hindered β-diketone(4,4-dimethyl-1-(4-dodecylphenyl)-1,3-pentanedione) was studied.The effects of the copper concentration,the total ammonia concentration,the initial pH in the aqueous phase,the phase ratio,and the temperature on copper extraction ratio and ammonia extraction in loaded organic phase were investigated using this sterically hindered β-diketone.Under the conditions of temperature 25℃,contact time of two phases 30 min,phase ratio 1-1,concentration of copper 3 g/L,concentration of total ammonia 3 mol/L,aqueous pH 8.43,and the concentration of β-diketone in organic phase 20%(volume fraction),ammonia in aqueous phase is much lower to be extracted by organic phase(just 14.5 mg/L),while the extraction rate of copper is 95.09%.
文摘The poor dissolution characteristics of water-insoluble drugs are a major challenge for pharmaceutical scientists.Reduction of the particle size/increase in the surface area of the drug is a widely used and relatively simple method for increasing dissolution rates.The objective of this study was to improve solubility,release and comparability of dissolution of a poorly soluble drug using two different types of formulations(solid dispersions and microspheres).Hydrochlorothiazide was used as a model drug.The solid dispersions and microspheres were prepared by solvent evaporation method using ethyl cellulose,hydroxypropyl methylcellulose in different drug-to-carrier ratios(1:1,1:2 w:w).The prepared formulations were evaluated for interaction study by Fourier transform infrared spectroscopy,differential scanning calorimetry,percentage of practical yield,drug loading,surface morphology by scanning electron microscopy,optical microscopy and in-vitro release studies.The results showed no interaction between the drug and polymer,amorphous state of solid dispersions and microspheres,percentage yield of 42.53%to 78.10%,drug content of 99.60%to 99.64%,good spherical appearance in formulation VI and significant increase in the dissolution rate.
文摘In this paper, fibrillation properties of solvent - spun cellulose fiber and some influencing factors are analyzed based on the experiment results. It is pointed out that special textile styles and aesthetic appearance could be obtained by controlling the fibrillation.
基金Projects(52034002,U1802253)supported by the National Natural Science Foundation of ChinaProject(2019YFC1908401)supported by the National Technology Support Project of China。
文摘This work investigated the separation of potassium from sodium in alkaline solution using substituted phenol-based extractants.Superior potassium extraction was achieved with 4-tert-butyl-2-(α-methylbenzyl)phenol(t-BAMBP)than 4-sec-butyl-2-(α-methylbenzyl)phenol(BAMBP).The optimum conditions for the extraction were 1 mol/L t-BAMBP,3:1 volumetric phase ratio(O/A),and two extraction stages.After cross-current extraction,the extraction ratio of potassium reached 90.8%.After scrubbing with deionised water at phase ratio of 4:1 and scrubbing stage of 4,a sodium scrubbing efficiency of 88.2%was obtained.After stripping using 1 mol/L H_(2)SO_(4) at phase ratio of 3:1,the stripping efficiency of potassium reached 94.2%.The potassium/sodium(K/Na)concentration ratio increased 14.3 times from 0.15 in the feed solution to 2.3 in the stripping solution.The efficient separation of potassium from sodium in alkaline solution was achieved via solvent extraction with t-BAMBP.
文摘The characteristics and research methods of terrigenous organic hydrocarbon-generated source rock in coal measures are studied in this thesis. After abundance of organic matters, pyrolysis parameter of rocks and hydrocarbon generated capacity of macerals are basically discussed in coal measures of the Cretaceous Muleng-Chengzihe formation in Suibin depression in Sanjang basin, the hydrocarbon generated grade in coal-genera^ted source rock is ascertained in this depression. At last, we think that it is a main attack prospect in coal-genera^ted hydrocarbons study in the future to research the macerals of coal measures organic source rock and to build a criterion to classify the coal-generated hydrocarbons in Northeast region.
基金Supported by the National'High Technology Research and Development Program of China (2009AA02Z207), the National Natural Science Foundation of China (20876012) and the Hi-Tech Research and Development Program of China (2009AA03Z232, 2010AA101601).
文摘Wax esters were synthesized in a solvent free system catalyzed by immobilized lipase from Candida sp. 99-125, with oleic acid and cetyl alcohol. The effects of substrate molar ratio, lipase dosage and water removal were investigated in a 50 ml flask incubated in a thermostatic cultivation cabinet. The optimized conditions were: temperature 40 ℃, shaking at 170 r·min-1, acid/alcohol molar ratio 1:0.9, lipase dosage in 10% (by mass) of oleic acid, and open reaction for water removal. As a result, the conversion rate reached 98% for reaction of 8 h. The volume of reactor was scaled up to 1 L three-neck flask. The optimized parameters were: 200 r·min-1 agitation speed, 2.5% (by mass) lipase dosage, others were the same as the parameters described above. The conversion rate reached 95% for reaction of 24 h. The lipase retained 46% conversion rate after reuse for 6, 7 batches. The products were purified by removing remained cetyl alcohol and fatty acids with ethanol and saturated sodium carbonate so-lution, respectively. The purity of the wax ester, cetyl oleate, was 96%. The physical and chemical properties of cetyl oleate were tested and compared with those of jojoba oil. The results show that the product cetyl oleate has great potential to use as the substitute of natural jojoba oil.
基金Supported by the National Natural Science Foundation of China (Nos. 20473055 and 20773089)the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (No. 20071108-18-15)
文摘Electronic structures and absorption spectra properties of complex 8-((trimethoxysilyl)methylthio)quinoline.SnCh in gas phase and MeCN media have been investigated by using DFT/TD-DFT method. The calculated lowest-energy absorption band shows different mechanisms under these two conditions, and it bears LMCT/LLCT/ILCT character in MeCN solution and LLCT/ILCT character in gas phase. The calculated absorption bands of the title complex in MeCN solvent are in good agreement with the experimental results, and calculation results indicate that the very weak experimentally observed lowest-energy absorption band of the title complex in MeCN solvent originates from the spin-forbidden singlet-triplet transitions.
基金Supported by the China National Science and Technology Major Project (2016ZX05024-003)
文摘The Bohai Bay Basin is a typical oil-prone basin, in which natural gas geological reserves have a small proportion. In this basin, the gas source rock is largely medium-deep lake mudstone with oil-prone type Ⅱ2-Ⅱ1 kerogens, and natural gas preservation conditions are poor due to active late tectonic movements. The formation conditions of large natural gas fields in the Bohai Bay Basin have been elusive. Based on the exploration results of Bohai Bay Basin and comparison with large gas fields in China and abroad, the formation conditions of conventional large-scale natural gas reservoirs in the Bohai Bay Basin were examined from accumulation dynamics, structure and sedimentation. The results show that the formation conditions of conventional large natural gas reservoirs in Bohai Bay Basin mainly include one core element and two key elements. The core factor is the strong sealing of Paleogene "quilt-like" overpressure mudstone. The two key factors include the rapid maturation and high-intensity gas generation of source rock in the late stage and large scale reservoir. On this basis, large-scale nature gas accumulation models in the Bohai Bay Basin have been worked out, including regional overpressure mudstone enriching model, local overpressure mudstone depleting model, sand-rich sedimentary subsag depleting model and late strongly-developed fault depleting model. It is found that Bozhong sag, northern Liaozhong sag and Banqiao sag have favorable conditions for the formation of large-scale natural gas reservoirs, and are worth exploring. The study results have important guidance for exploration of large scale natural gas reservoirs in the Bohai Bay Basin.
文摘In order to clarify the mechanism and the complex formed in the extraction of divalent Mn by alkylphosphonic acid monoester, the solid complex has been prepared by mono (2-ethylhexyl)-2-ethylhexyl phosphate, HEH(EH)P, HA with divalent Mn. The elemental analysis, magnetic susceptibility and thermogravimetry have been determined for the solid complex of HEH(EH)P-Mn(II) and the infrared spectrum has been carried out in comparison to the extractant HEH(EH)P. The extracted compound has also been studied by electronic and electron spin resonance spectroscopy in octane solvent and solid state at room temperature. On the basis of the measurements, it is concluded that the structure of the solid polymeric species MnA_2 is in a tetrahedral arrangement.
文摘ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these materials have acquired renewed importance due to the new explored nanolayer properties of modern devices. In addition, as shown in this work they can be grown using uncomplicated synthesis techniques based on the deposition in vapour phase of the elemental precursors. This work presents the results obtained from the deposition of nanolayers of these materials using the precursor vapour on GaAs and GaSb (001) substrates. This growth technique, extensively known as atomic layer deposition (ALD), allows the layers growth with nanometric dimension. The main results presented in this work are the used growth parameters and the results of the structural characterization of the layers by the means of Raman spectroscopy measurements. Raman scattering shows the peak corresponding to longitudinal optical (LO)-ZnTe, which is weak and slightly redshift in comparison with that reported for the ZnTe bulk at 210 cm^-1. For the case of the CdTe nanolayer, Raman spectra presented the LO-CdTe peak, which is indicative of the successful growth of the layer. Its weak and slightly redshift in comparison with that reported for the CdTe bulk can be related with the nanometric characteristic of this layer. The performed high-resolution X-ray diffraction (HR-XRD) measurement allows to study some important characteristics such as the crystallinity of the grown layer. In addition, the HR-XRD measurement suggests that the crystalline quality has dependence on the growth temperature.
文摘The growth of crystals of the high T c oxide superconductors has been hampe red by the complexities of the materials and their phase diagrams.The most common crys tal growth technique adopted for these oxides is the “flux”method,where the st arting materials are solved in a melt,which is usually formed by excess CuO and BaO or a KCl/NaCl mixture.The crystals are produced by slow cooling of the heate d solvent.This method,however,suffers from several disadvantages: (1) the crystals are contaminated with the crucible material, (2) the crystals are difficult to remove from the crucible, (3) the crystals contain flux inclusions.
文摘Anri-idiotypic monoclonal antibody (Mab Ab2 ) by MAb COC166-9 against ovarian serous papillary adenocarcinoma was prepared. Hybridomas of Ab2 screened by sandwich ELISA and immunocompetitive inhibition tests were procured and named as 6B11 and 1H12. The number of their chromosomes were 93 and 91, and DNA analysis also proved the characteristics of hybridomas. These Ab2s could induce delayed type hypersensitivity (DTH), the cellular immune response. The results of the immune reaction of 6B11 with SKOV3 (ovarian carcinoma cell line) were similar to OC166-9 (Ag), the positive control, while 1H12 was weaker. Anti-and-idiotypic antibody (Ab3) was also raised by 6B11 and 1H12 respectively. They all showed positive immunohistochemical stainings with ovarian serous adenocarcinoma tissue sections and immunocytochemical stainings with SKOV3 cells as was shown by COC166-9. In the antibody dependent cell mediated cytotoxicity (ADCC) tests, they showed no differences against SKOV3 as compared with COC166-9. We anticipate that 6B11 and 1H12 may be used as vaccines against ovarian carcinoma and may provide a clue for its prevention and treatment.