This paper systematically categorizes the primary composition of star anise(Illicium verum),including volatile oils,flavonoids,phenolic acids,and sesquiterpene lactones,and further analyzes the pharmacological activit...This paper systematically categorizes the primary composition of star anise(Illicium verum),including volatile oils,flavonoids,phenolic acids,and sesquiterpene lactones,and further analyzes the pharmacological activities,such as antibacterial,analgesic,anti-inflammatory,and antioxidant effects.Additionally,it summarizes key aspects of extraction techniques,analytical methods,and fresh material processing technologies.The objective is to provide a robust foundation for enhancing research methods and technological standards related to star anise,thereby improving resource utilization efficiency and facilitating its industrial applications.展开更多
Immiscible alloys have attracted growing interest for their valuable physical and mechanical properties. However, their production is difficult because of metallurgical problems in which there is a serious tendency fo...Immiscible alloys have attracted growing interest for their valuable physical and mechanical properties. However, their production is difficult because of metallurgical problems in which there is a serious tendency for gravity separation in the region of the miscibility gap. So far the study on the liquid separation mechanism is still one of the important projects in the spatial materials science and the spatial fluid science. The studied results about the liquid phase separating mechanism of immiscible alloys are presented, at the same time the preparation techniques of homogeneous immiscible alloys are summarized, and the existing problems and the related researching areas in the future are also pointed out.展开更多
A novel process which can purify the organic solvents from their azeotropes with water is proposed. In this process,water can be drained off both from bottom and overhead of tower at the same time,and the organic solv...A novel process which can purify the organic solvents from their azeotropes with water is proposed. In this process,water can be drained off both from bottom and overhead of tower at the same time,and the organic solvent is concentrated in the tower and accumulated in the middle vessel at last. So the progress is time-shortened and energy-saving. The product purity is 99. 8% and the product yield is more than 99.5%. Simulation of liquid-liquid equilibrium (LLE) and the equipment operation data agree well with the experiment.展开更多
This paper reviews the development course of separating rare earths with acid phosphorus extractants,including extraction chemistry(thermodynamics and kinetics), separation process and industrial application, the loss...This paper reviews the development course of separating rare earths with acid phosphorus extractants,including extraction chemistry(thermodynamics and kinetics), separation process and industrial application, the loss/degradation of extractants, etc.展开更多
For an AB/BC countercurrent extraction separation using organic feed, the conditions to have minimum amount of ex- tracting solvent （Smin） and minimum amount of scrubbing agent solution （Wmin） were discussed, and ...For an AB/BC countercurrent extraction separation using organic feed, the conditions to have minimum amount of ex- tracting solvent （Smin） and minimum amount of scrubbing agent solution （Wmin） were discussed, and the formulae of both Sroin and Wmin were deduced. It was shown that only when the ratio of flowrate of central component B leaving aqueous outlet to that leaving organic outlet took a certain optimal value, the AB/BC separation could have Smin as well as Wmin, and this optimal ratio was decided by the separation factors between the three components but independent of feed composition. Smin was only relative to the separation factor of A/C pair but regardless of the separation factors of other pairs as well as feed composition, whereas Wmin was determined by the separation factors between the components together with feed composition. Meanwhile it was also found that the organic stream out of feed stage was same composition as the initial organic feed when the separation system was given by the two minimum amounts and its steady state was achieved. Finally the results above were used to design a LuYb/YbTm separation case and the stage-wise compositions of each component in both the organic and the aqueous phase at steady state were given by computer simulation.展开更多
Aim: To evaluate the comparative effectiveness of real-time sperm separation technique (Wang's tube method) andother two conventional methods in isolating high-quality sperm preparation, and to compare the spouse ...Aim: To evaluate the comparative effectiveness of real-time sperm separation technique (Wang's tube method) andother two conventional methods in isolating high-quality sperm preparation, and to compare the spouse pregnancy ratein intrauterine insemination (IUI) with sperm preparations isolated by these methods. Methods: The effectivenessof the real-time sperm separation technique, the conventional swim-up and the Percoll discontinuous density gradientmethods in isolating sperm preparations from 60 infertile patients (20 with apparently normal semen and 40, abnormalsemen contaminated with microorganisms and other impurities) was evaluated and compared. The microorganisms to beremoved included bacteria, vires, Chlamydia trachomaticum, Ureaplsama urealyticum, etc. The spouse pregnancyrates in IUI with sperm preparations isolated by these three techniques from 80 oligoasthenoteratospermic patients werealso compared. Results: The quality (including the percentages of normal form, normal-chromatin and motilesperm, and the grade of motility) of sperm obtained by the real-time sperm separation technique was much higher ( P< 0.01) as compared with those by the other two methods. The Wang's tube method was also more effective in remov-ing microorganisms and other impurities. The method provided a higher IUI pregnancy rate than the other two spermseparation techniques ( P < 0.05). Conclusion: The real-time sperm separation technique is the most effectivemethod so far available in isolating high-quality sperm samples to be used in assisted reproduction.展开更多
Four techniques, Soxhlet extraction (SOX), ultrasonic extraction (USE), fluidized-bed extraction (FBE) and acce-lerated solvent extraction (ASE) with different solvents (methanol, hexane/acetone and acetonitrile) were...Four techniques, Soxhlet extraction (SOX), ultrasonic extraction (USE), fluidized-bed extraction (FBE) and acce-lerated solvent extraction (ASE) with different solvents (methanol, hexane/acetone and acetonitrile) were used for theextraction of DDT analogues in sediments. Results revealed that the four extraction techniques had high recoveries (>86.0%) with low standard deviations (< 12.0%) for most of DDT analogues, meaning that they could all successfully extractDDT analogues in sediments. Accelerated solvent extraction using methanol and hexane/acetone (1:1), fluidized-bedextraction using hexane/acetone (1:1) and the ultrasonic extraction using hexane/acetone (1:1) were comparable or betterthan Soxhlet extraction using hexane/acetone (1:1). Considering solvent- and time-consumption, level of automation,and environmental risk, accelerated solvent extraction with hexane/acetone (1:1) was better than the other extractiontechniques.展开更多
Hollow-fiber liquid-phase microextraction(HF-LPME)and electromembrane extraction(EME)are miniaturized extraction techniques,and have been coupled with various analytical instruments for trace analysis of heavy metals,...Hollow-fiber liquid-phase microextraction(HF-LPME)and electromembrane extraction(EME)are miniaturized extraction techniques,and have been coupled with various analytical instruments for trace analysis of heavy metals,drugs and other organic compounds,in recent years.HF-LPME and EME provide high selectivity,efficient sample cleanup and enrichment,and reduce the consumption of organic sol-vents to a few micro-liters per sample.HF-LPME and EME are compatible with different analytical in-struments for chromatography,electrophoresis,atomic spectroscopy,mass spectrometry,and electrochemical detection.HF-LPME and EME have gained significant popularity during the recent years.This review focuses on hollow fiber based techniques(especially HF-LPME and EME)of heavy metals and pharmaceuticals(published 2017 to May 2019),and their combinations with atomic spectroscopy,UV-VIS spectrophotometry,high performance liquid chromatography,gas chromatography,capillary elec-trophoresis,and voltammetry.展开更多
Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techni...Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techniques are an efficient and energy saving technology. Vapor permeation can be applied to recovery of organic solvents from exhaust streams. Membrane contactor could be used for removing or recovering VOCs from air or wastewater. Pervaporation and vapor permeation are viable methods for removing VOCs from wastewater to yield a VOC concentrate which could either be destroyed by conventional means, or be recycled for reuse.展开更多
A significant development in the theory of countercurrent extraction will be presented in this article. New expressions of the term in countercurrent extraction process analysis, “Adjacent Stage Impurity Ratio” (ASI...A significant development in the theory of countercurrent extraction will be presented in this article. New expressions of the term in countercurrent extraction process analysis, “Adjacent Stage Impurity Ratio” (ASIR), are deduced. Furthermore, based on the term together with mass balance and extraction equilibrium, the conditions where a given countercurrent extraction separation operation can have minimum amounts of both extracting solvent and scrubbing agent solution can be estimated, and the equations of the two minimum amounts can be deduced. It was found that the equations for a two-component separation using a single aqueous or organic feed are exactly the same as they appeared in the theory initially established in 1970s. Unlike its earlier version, the present derivation does not involve feed-stage-composition hypothesis, and also has the advantage of dealing with a double-feed system where both aqueous and organic feeds are simultaneously employed whereas the earlier theory can only analyze a separation using a single aqueous or organic feed.展开更多
In recent years, photosynthetic microalgae regained attention for biodiesel production. For efficient utilization of microalgae, a number of criteria including a strain with high biomass and lipid productivities and e...In recent years, photosynthetic microalgae regained attention for biodiesel production. For efficient utilization of microalgae, a number of criteria including a strain with high biomass and lipid productivities and employment of effective and reliable methods for oil extraction from the obtained biomass should be met. Recently, we have isolated and identified three thermo-resistant green microalgae strains, namely;Scenedesmus sp. ME02, Hindakia tetrachotoma ME03 and Mic-ractinium sp. ME05. In this study, we compared percent lipid content of thermos-tolerant mic-roalgal strains using the following solvent extraction methods: Soxhlet, Bligh and Dyer and Folch methods with or without assisted cell disruption techniques including lyophilization, homogenization, ultrasonication, bead and microwave-assisted. The highest increase in lipid yield was obtained with a combination of lyophilization and ultrasonication techniques together with Soxhlet method: 27% of total dry weight for Micractinium sp. ME05. We conclude that lyophilization and ultrasonication are effective assistance methods for lipid extraction from thermo-resistant microalgae.展开更多
A series of changes occur in the remaining alveolar process after whole tooth extraction.The basic question is,why do the bony walls(especially the labial/buccal)get resorbed immediately after the tooth is removed?Thi...A series of changes occur in the remaining alveolar process after whole tooth extraction.The basic question is,why do the bony walls(especially the labial/buccal)get resorbed immediately after the tooth is removed?This could be because,with cementum of the concerned tooth and its periodontal ligament,the supporting bundle bone is dependent on the presence of the tooth.This loss can be compensated using numerous techniques,such as socket grafting using various biomaterials to preserve the alveolar bone and buccal grafting with guided tissue regeneration to increase the thickness of buccal bone or placement of implant immediately.However,none of these techniques prevent the modelling of the alveolar bone post-extraction.Few studies have demonstrated that preservation of the roots in the alveolar process maintains the bone volume and facilitates vertical bone growth.A histological study in animals and humans has shown that the retained root shell does not pose any interference in the osseointegration of the implant(if placed simultaneously).Although various names have been proposed to describe the concept of retaining full or part of the root to prevent the resorption of the ridge,socket-shield and pontic-shield are the two most commonly used terms worldwide.The extraction of the whole tooth might be the choice of therapy when socket-shield or pontic-shield is not possible due to anatomical variations,infections,or lack of clinical expertise.Irrespective of the size,when a whole root or a root fragment(is left in situ),it is the dentist’s ethical duty to advise/inform the patient and ensure repeated clinical and radiographic follow-up.The present study aimed to highlight the current status of these techniques,their benefits,and possible complications and address whether the paradigm of the teeth extraction methods should be altered.展开更多
Enlarging the steric hindrance to the molecular structures of extractants is a common way to improve their selectivity.To improve the separation factor of thorium(Ⅳ)and cerium(Ⅳ),cyclic groups having large steric hi...Enlarging the steric hindrance to the molecular structures of extractants is a common way to improve their selectivity.To improve the separation factor of thorium(Ⅳ)and cerium(Ⅳ),cyclic groups having large steric hindrance such as phenyl,cyclohexyl,and benzyl were introduced into theα-aminophosphonate extractant molecules.Bis(2-ethylhexyl)((phenylamino)methyl)phosphonate(PAMP),bis(2-ethylhexyl)((cyclohexylamino)methyl)phosphonate(CAMP),and bis(2-ethylhexyl)((benzylamine)methyl)phosphate(BAMP)were synthesized and applied in the separation and recovery of thorium(Ⅳ)and cerium(Ⅳ)from sulfuric acid solution.The separation ability between cerium(Ⅳ)and thorium(Ⅳ)descends in the order of CAMP>BAMP≈Cextrant230>DEHAMP>>PAMP,which is consistent with the decreasing order of steric hindrance.Nearly non-extraction of both cerium(Ⅳ)and thorium(Ⅳ)and the lowest separation ability for PAMP will be due to the conjugation of the lone pair of the amino N atom and benzene ring in PAMP.Furthermore,the extraction of REs(Ⅲ)by CAMP is lower than that of thorium(Ⅳ).Thermodynamic parameters(ΔG^(0),ΔH^(0),ΔS^(0))and extraction equilibrium constants were determined.An extraction process was developed to separate and retrieve thorium(Ⅳ)and cerium(Ⅳ)from a bastnaesite leaching solution.The final product purity of CeO2and ThO2is 99%and 98.4%,respectively,and the yields are 90.2%and 97.6%,respectively.展开更多
AIM:To evaluate the effect of femtosecond laser small incision lenticule extraction(SMILE)on the binocular visual function in myopic patients with glasses-free threedimensional(3D)technique.METHODS:Totally 50 myopic p...AIM:To evaluate the effect of femtosecond laser small incision lenticule extraction(SMILE)on the binocular visual function in myopic patients with glasses-free threedimensional(3D)technique.METHODS:Totally 50 myopic patients(39 females and 11 males)with SMILE were enrolled in this prospective study.The glasses-free 3D technique was used to evaluate the binocular visual function in these subjects including static stereopsis,dynamic stereopsis,foveal suppression,and binocular balance point of signal to noise ratio(s/n ratio).All subjects received measurements in 1d before operation,and 1d,1wk,and 1mo postoperatively.RESULTS:Both static and dynamic stereopsis showed no significant difference after SMILE.The foveal suppression improved significantly 1wk and 1mo after SMILE(P=0.005 and P=0.007 respectively).The binocular balance point of signal to noise ratio showed a significant improvement 1d,1wk and 1mo after SMILE for both eyes(P<0.001 for each eye respectively).CONCLUSION:Glasses-free 3D technique can be used to evaluate the effect of SMILE on the binocular visual function in myopic patients perceptively,and SMILE can improve both foveal suppression and binocular imbalance in these patients.展开更多
Since the early days of assisted reproductive technology(ART),the importance of sperm processing,employed to separate the motile,morphologically normal sperm from the semen,has been shown to be beneficial.The aim of t...Since the early days of assisted reproductive technology(ART),the importance of sperm processing,employed to separate the motile,morphologically normal sperm from the semen,has been shown to be beneficial.The aim of the semen processing technique has been to remove seminal plasma and facilitate capacitation.Additionally,the presence of leukocytes,bacteria,and dead spermatozoa has been shown to be detrimental as it may cause oxidative stress that has an adverse effect on oocyte fertilization and embryo development.Hence,removal of leukocytes,bacteria,and dead spermatozoa is an important step of sperm processing for assisted reproduction.Currently,several sperm processing techniques have been evolved and optimized in the field of assisted reproduction.The requirements for in vitro fertilization(IVF),intracytoplasmic sperm injection(ICSI),and testicular sperm extraction(TESE)are different than those of intrauterine insemination(IUI).The yield of as many motile,morphologically normal sperm as possible is a prerequisite for the success of IVF insemination procedure.In ICSI,where injection of a single spermatozoon into the oocyte is performed by the embryologist,sperm selection techniques play a crucial role in the ICSI procedure.Finally,sperm retrieval in TESE samples with very low number of sperm may be challenging and requires extra care during sample processing.Additionally,sperm cryopreservation is necessary in TESE cases in order to avoid multiple biopsies.展开更多
In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by io...In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by ion morphology pretreatme nt and solvent extraction.An acidic V(Ⅴ)/W(Ⅵ)solution was obtained using the me mbrane electrolysis method without adding any other chemical reagents.In addition,Na was recovered in the form of NaOH by product,avoiding the generation of Na containing wastewater.The electrolysis parameters were investigated,the lowest power consumption of 3063 kW·h·t^(-1)NaOH was obtained at a current density of 125 A·m^(-2)and an initial NaOH concentration of 2 mol·L^(-1).After electrolysis,oxalic acid was added to the acidic V/W containing solution,converting V(Ⅴ)negative ion to V(Ⅳ)positive ion.Since W(Ⅵ)ion state remained in negative form,the generation of heteropolyacid ions(W_(x)V_(y)O_(z)^(n-))was prevented.It was found that under the condition of oxalic acid addition/theoretical consumption 1.2 and reaction temperature 75℃,100%V(Ⅴ)was co nverted to V(Ⅳ4).Using 10%N263+10%noctanol+80%sulfonated kerosene as extractant,the highest W(Ⅵ)/V(Ⅳ)separation coefficient of 7559.76was obtained at pH=1.8,O:A ratio=1:1 and extraction time 15 min.With 2 mol·L^(-1)NaOH as stripping reagent,the W stripping efficiency reached 98.50%at O:A ratio=2:1 after 4-stages of stripping.The enrichment of V remained in the solution was realized using P204 as extractant and 20%(mass)H_(2)SO_(4)as stripping reagent.The parameters of extraction/stripping process were investigated,using 10%P204+10%TBP+80%sulfonated kerosene as extractant,the V extraction efficiency reached 97.50%at O:A ratio=1:2after 4 stages of extraction.Using 20%H_(2)SO_(4)as the stripping reagent,the V stripping efficiency was 98.30%at an O:A ratio of 4:1 after five stage s of stripping.After the entire process,a high-purity VOSO_(4)and Na_(2)WO_(4)product solutions were obtained with V/W recovery efficiency 95.84%/98.50%,separately.This study examined a more effective and cleaner method for separating V/W/Na in Na_(2)WO_(4)/NaVO_(3)solution,which may serve as a reference for the separation and recovery of V/W/Na in waste SCR catalysts.展开更多
This review paper was prepared at Department of Zoology, University of Gujrat, Pakistan during 2014-2015. The data for the two decades, DNA Extraction from Insects by Using Different Techniques was compiled through a ...This review paper was prepared at Department of Zoology, University of Gujrat, Pakistan during 2014-2015. The data for the two decades, DNA Extraction from Insects by Using Different Techniques was compiled through a thorough review of many research articles published in various journals of international repute. Insects are very important economically and ecologically for human due to their various roles, as pests, decomposer in nutrition cycle, vector for the transmission of certain diseases and a source of medically and economically important products. To identify insect, and for research on their role, different molecular techniques are used. For each molecular technique, high quality DNA is required, which is extracted from the insects by different techniques. The selection of DNA extraction technique is depended upon specimen under study, time required for extraction, economical stander of technique due to reagents and equipment used for extraction and most importantly extracted DNA quality. In this paper, most frequently used techniques for DNA extraction from insect with different size and condition are outlined. This paper is only a guide for these techniques and we describe them briefly.展开更多
In recent years,with the rapid developme nt of the econo my and society,pollution of valuable metal ions in wastewater has become a major challenge to environmental sustainability.In order to solve the pollution cause...In recent years,with the rapid developme nt of the econo my and society,pollution of valuable metal ions in wastewater has become a major challenge to environmental sustainability.In order to solve the pollution caused by metal ions,researchers have conducted continuous re searches and explored various re mediation methods.Crown ether has attracted great attention because of its ionic radius and cavity size matching well with metal ions,which makes it have the ability to selectively complex metal ions.This unique property enables the directed removal and recovery of metal ions and makes crown ethers increasingly popular in extraction and separation processes.In this paper,the research progress of crown ethers in the extraction and separation of valuable metal ions was reviewed,with emphasis on the principles,extraction systems and the key factors affecting the extraction process.This study can provide some technical support for the application of separation and extraction of valuable metal ions by crown ether.展开更多
[Objectives]This study was conducted to investigate the extraction technology of celastrol from Celastrus orbiculatus Thunb.[Methods]Solvent ultrasonic extraction was selected,and with the content of celastrol as the ...[Objectives]This study was conducted to investigate the extraction technology of celastrol from Celastrus orbiculatus Thunb.[Methods]Solvent ultrasonic extraction was selected,and with the content of celastrol as the evaluation index,the effects of different solvents,extraction time,temperatures and material-to-liquid ratios on the extraction rate of celastrol were investigated by single factor and orthogonal experiments.[Results]The optimal extraction conditions were as follows:a solvent ratio of petroleum ether to ethyl acetate at 1∶1,a ratio of solvent to material at 10∶1(v/w),extraction time of 30 min,and an extraction temperature at 30℃.[Conclusions]This method has high extraction rate,and is simple and feasible.展开更多
Hydrograph separation is a fundamental catchment descriptor,revealing information about sources of water in runoff generation processes. The water isotopes are ideal tracers in studying hydrological processes since th...Hydrograph separation is a fundamental catchment descriptor,revealing information about sources of water in runoff generation processes. The water isotopes are ideal tracers in studying hydrological processes since the isotope fractionation produces a natural labeling effect within the hydrologic cycle. The water isotope technique has become one of effective means for investigating complex hydrologic system on a catchment scale. This paper reviews the progress on the use of stable water isotope techniques in catchment hydrograph separation in last decades. Also,the isotope mixing model for hydrograph separation and its uncertainties are explained in detail. In future research,there are three hot issues in the use of isotopic hydrograph separation（ IHS） ： integrating new approaches into IHS,calibration and verification of IHS model and IHS application in large river basins.展开更多
基金Supported by Project of Guangxi Zhuang Autonomous Region Administration of Traditional Chinese Medicine(GXZYA20230001)Research Fund Project of Guangxi Zhuang Autonomous Region Medicinal Botanical Garden(202304).
文摘This paper systematically categorizes the primary composition of star anise(Illicium verum),including volatile oils,flavonoids,phenolic acids,and sesquiterpene lactones,and further analyzes the pharmacological activities,such as antibacterial,analgesic,anti-inflammatory,and antioxidant effects.Additionally,it summarizes key aspects of extraction techniques,analytical methods,and fresh material processing technologies.The objective is to provide a robust foundation for enhancing research methods and technological standards related to star anise,thereby improving resource utilization efficiency and facilitating its industrial applications.
文摘Immiscible alloys have attracted growing interest for their valuable physical and mechanical properties. However, their production is difficult because of metallurgical problems in which there is a serious tendency for gravity separation in the region of the miscibility gap. So far the study on the liquid separation mechanism is still one of the important projects in the spatial materials science and the spatial fluid science. The studied results about the liquid phase separating mechanism of immiscible alloys are presented, at the same time the preparation techniques of homogeneous immiscible alloys are summarized, and the existing problems and the related researching areas in the future are also pointed out.
文摘A novel process which can purify the organic solvents from their azeotropes with water is proposed. In this process,water can be drained off both from bottom and overhead of tower at the same time,and the organic solvent is concentrated in the tower and accumulated in the middle vessel at last. So the progress is time-shortened and energy-saving. The product purity is 99. 8% and the product yield is more than 99.5%. Simulation of liquid-liquid equilibrium (LLE) and the equipment operation data agree well with the experiment.
基金Project supported by the National Basic Research Program of China(973 Program,2006CB403302)
文摘This paper reviews the development course of separating rare earths with acid phosphorus extractants,including extraction chemistry(thermodynamics and kinetics), separation process and industrial application, the loss/degradation of extractants, etc.
基金Project supported by the 973 Program-Major Project of Chinese National Programs for Fundamental Research and Development(2012CBA01200)
文摘For an AB/BC countercurrent extraction separation using organic feed, the conditions to have minimum amount of ex- tracting solvent （Smin） and minimum amount of scrubbing agent solution （Wmin） were discussed, and the formulae of both Sroin and Wmin were deduced. It was shown that only when the ratio of flowrate of central component B leaving aqueous outlet to that leaving organic outlet took a certain optimal value, the AB/BC separation could have Smin as well as Wmin, and this optimal ratio was decided by the separation factors between the three components but independent of feed composition. Smin was only relative to the separation factor of A/C pair but regardless of the separation factors of other pairs as well as feed composition, whereas Wmin was determined by the separation factors between the components together with feed composition. Meanwhile it was also found that the organic stream out of feed stage was same composition as the initial organic feed when the separation system was given by the two minimum amounts and its steady state was achieved. Finally the results above were used to design a LuYb/YbTm separation case and the stage-wise compositions of each component in both the organic and the aqueous phase at steady state were given by computer simulation.
基金Project suppocted by the Youth Science Research Foundation of the Department of Public Health,Guangdong Province(No.B199121)
文摘Aim: To evaluate the comparative effectiveness of real-time sperm separation technique (Wang's tube method) andother two conventional methods in isolating high-quality sperm preparation, and to compare the spouse pregnancy ratein intrauterine insemination (IUI) with sperm preparations isolated by these methods. Methods: The effectivenessof the real-time sperm separation technique, the conventional swim-up and the Percoll discontinuous density gradientmethods in isolating sperm preparations from 60 infertile patients (20 with apparently normal semen and 40, abnormalsemen contaminated with microorganisms and other impurities) was evaluated and compared. The microorganisms to beremoved included bacteria, vires, Chlamydia trachomaticum, Ureaplsama urealyticum, etc. The spouse pregnancyrates in IUI with sperm preparations isolated by these three techniques from 80 oligoasthenoteratospermic patients werealso compared. Results: The quality (including the percentages of normal form, normal-chromatin and motilesperm, and the grade of motility) of sperm obtained by the real-time sperm separation technique was much higher ( P< 0.01) as compared with those by the other two methods. The Wang's tube method was also more effective in remov-ing microorganisms and other impurities. The method provided a higher IUI pregnancy rate than the other two spermseparation techniques ( P < 0.05). Conclusion: The real-time sperm separation technique is the most effectivemethod so far available in isolating high-quality sperm samples to be used in assisted reproduction.
基金the Outstanding Youth Fund of the National Natural Science Foundation of China (No. 40325001),the National Key Basic Research and Development Program of China (No. 2002CB410805) and the Ocean University ofChina.
文摘Four techniques, Soxhlet extraction (SOX), ultrasonic extraction (USE), fluidized-bed extraction (FBE) and acce-lerated solvent extraction (ASE) with different solvents (methanol, hexane/acetone and acetonitrile) were used for theextraction of DDT analogues in sediments. Results revealed that the four extraction techniques had high recoveries (>86.0%) with low standard deviations (< 12.0%) for most of DDT analogues, meaning that they could all successfully extractDDT analogues in sediments. Accelerated solvent extraction using methanol and hexane/acetone (1:1), fluidized-bedextraction using hexane/acetone (1:1) and the ultrasonic extraction using hexane/acetone (1:1) were comparable or betterthan Soxhlet extraction using hexane/acetone (1:1). Considering solvent- and time-consumption, level of automation,and environmental risk, accelerated solvent extraction with hexane/acetone (1:1) was better than the other extractiontechniques.
基金supported by the Higher education commission of Pakistan(NRPU No.20-3925/R&D/NRPU/HEC/2014)PAK-US science and technology cooperation(Pak-US No6-4/PAK-US/HEC/2015/04)Pakistan science foundation joint research projects with MSRT,Iran(No.PSF-MSRT/Env/KP-AWKUM)。
文摘Hollow-fiber liquid-phase microextraction(HF-LPME)and electromembrane extraction(EME)are miniaturized extraction techniques,and have been coupled with various analytical instruments for trace analysis of heavy metals,drugs and other organic compounds,in recent years.HF-LPME and EME provide high selectivity,efficient sample cleanup and enrichment,and reduce the consumption of organic sol-vents to a few micro-liters per sample.HF-LPME and EME are compatible with different analytical in-struments for chromatography,electrophoresis,atomic spectroscopy,mass spectrometry,and electrochemical detection.HF-LPME and EME have gained significant popularity during the recent years.This review focuses on hollow fiber based techniques(especially HF-LPME and EME)of heavy metals and pharmaceuticals(published 2017 to May 2019),and their combinations with atomic spectroscopy,UV-VIS spectrophotometry,high performance liquid chromatography,gas chromatography,capillary elec-trophoresis,and voltammetry.
基金TheNationalNaturalScienceFoundationofChina (No .2 9836 16 0 )
文摘Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techniques are an efficient and energy saving technology. Vapor permeation can be applied to recovery of organic solvents from exhaust streams. Membrane contactor could be used for removing or recovering VOCs from air or wastewater. Pervaporation and vapor permeation are viable methods for removing VOCs from wastewater to yield a VOC concentrate which could either be destroyed by conventional means, or be recycled for reuse.
文摘A significant development in the theory of countercurrent extraction will be presented in this article. New expressions of the term in countercurrent extraction process analysis, “Adjacent Stage Impurity Ratio” (ASIR), are deduced. Furthermore, based on the term together with mass balance and extraction equilibrium, the conditions where a given countercurrent extraction separation operation can have minimum amounts of both extracting solvent and scrubbing agent solution can be estimated, and the equations of the two minimum amounts can be deduced. It was found that the equations for a two-component separation using a single aqueous or organic feed are exactly the same as they appeared in the theory initially established in 1970s. Unlike its earlier version, the present derivation does not involve feed-stage-composition hypothesis, and also has the advantage of dealing with a double-feed system where both aqueous and organic feeds are simultaneously employed whereas the earlier theory can only analyze a separation using a single aqueous or organic feed.
文摘In recent years, photosynthetic microalgae regained attention for biodiesel production. For efficient utilization of microalgae, a number of criteria including a strain with high biomass and lipid productivities and employment of effective and reliable methods for oil extraction from the obtained biomass should be met. Recently, we have isolated and identified three thermo-resistant green microalgae strains, namely;Scenedesmus sp. ME02, Hindakia tetrachotoma ME03 and Mic-ractinium sp. ME05. In this study, we compared percent lipid content of thermos-tolerant mic-roalgal strains using the following solvent extraction methods: Soxhlet, Bligh and Dyer and Folch methods with or without assisted cell disruption techniques including lyophilization, homogenization, ultrasonication, bead and microwave-assisted. The highest increase in lipid yield was obtained with a combination of lyophilization and ultrasonication techniques together with Soxhlet method: 27% of total dry weight for Micractinium sp. ME05. We conclude that lyophilization and ultrasonication are effective assistance methods for lipid extraction from thermo-resistant microalgae.
文摘A series of changes occur in the remaining alveolar process after whole tooth extraction.The basic question is,why do the bony walls(especially the labial/buccal)get resorbed immediately after the tooth is removed?This could be because,with cementum of the concerned tooth and its periodontal ligament,the supporting bundle bone is dependent on the presence of the tooth.This loss can be compensated using numerous techniques,such as socket grafting using various biomaterials to preserve the alveolar bone and buccal grafting with guided tissue regeneration to increase the thickness of buccal bone or placement of implant immediately.However,none of these techniques prevent the modelling of the alveolar bone post-extraction.Few studies have demonstrated that preservation of the roots in the alveolar process maintains the bone volume and facilitates vertical bone growth.A histological study in animals and humans has shown that the retained root shell does not pose any interference in the osseointegration of the implant(if placed simultaneously).Although various names have been proposed to describe the concept of retaining full or part of the root to prevent the resorption of the ridge,socket-shield and pontic-shield are the two most commonly used terms worldwide.The extraction of the whole tooth might be the choice of therapy when socket-shield or pontic-shield is not possible due to anatomical variations,infections,or lack of clinical expertise.Irrespective of the size,when a whole root or a root fragment(is left in situ),it is the dentist’s ethical duty to advise/inform the patient and ensure repeated clinical and radiographic follow-up.The present study aimed to highlight the current status of these techniques,their benefits,and possible complications and address whether the paradigm of the teeth extraction methods should be altered.
基金Project supported by the National Natural Science Foundation of China(92262301)。
文摘Enlarging the steric hindrance to the molecular structures of extractants is a common way to improve their selectivity.To improve the separation factor of thorium(Ⅳ)and cerium(Ⅳ),cyclic groups having large steric hindrance such as phenyl,cyclohexyl,and benzyl were introduced into theα-aminophosphonate extractant molecules.Bis(2-ethylhexyl)((phenylamino)methyl)phosphonate(PAMP),bis(2-ethylhexyl)((cyclohexylamino)methyl)phosphonate(CAMP),and bis(2-ethylhexyl)((benzylamine)methyl)phosphate(BAMP)were synthesized and applied in the separation and recovery of thorium(Ⅳ)and cerium(Ⅳ)from sulfuric acid solution.The separation ability between cerium(Ⅳ)and thorium(Ⅳ)descends in the order of CAMP>BAMP≈Cextrant230>DEHAMP>>PAMP,which is consistent with the decreasing order of steric hindrance.Nearly non-extraction of both cerium(Ⅳ)and thorium(Ⅳ)and the lowest separation ability for PAMP will be due to the conjugation of the lone pair of the amino N atom and benzene ring in PAMP.Furthermore,the extraction of REs(Ⅲ)by CAMP is lower than that of thorium(Ⅳ).Thermodynamic parameters(ΔG^(0),ΔH^(0),ΔS^(0))and extraction equilibrium constants were determined.An extraction process was developed to separate and retrieve thorium(Ⅳ)and cerium(Ⅳ)from a bastnaesite leaching solution.The final product purity of CeO2and ThO2is 99%and 98.4%,respectively,and the yields are 90.2%and 97.6%,respectively.
基金Supported by Sichuan Science and Technology Program(No.23NSFSC0856).
文摘AIM:To evaluate the effect of femtosecond laser small incision lenticule extraction(SMILE)on the binocular visual function in myopic patients with glasses-free threedimensional(3D)technique.METHODS:Totally 50 myopic patients(39 females and 11 males)with SMILE were enrolled in this prospective study.The glasses-free 3D technique was used to evaluate the binocular visual function in these subjects including static stereopsis,dynamic stereopsis,foveal suppression,and binocular balance point of signal to noise ratio(s/n ratio).All subjects received measurements in 1d before operation,and 1d,1wk,and 1mo postoperatively.RESULTS:Both static and dynamic stereopsis showed no significant difference after SMILE.The foveal suppression improved significantly 1wk and 1mo after SMILE(P=0.005 and P=0.007 respectively).The binocular balance point of signal to noise ratio showed a significant improvement 1d,1wk and 1mo after SMILE for both eyes(P<0.001 for each eye respectively).CONCLUSION:Glasses-free 3D technique can be used to evaluate the effect of SMILE on the binocular visual function in myopic patients perceptively,and SMILE can improve both foveal suppression and binocular imbalance in these patients.
文摘Since the early days of assisted reproductive technology(ART),the importance of sperm processing,employed to separate the motile,morphologically normal sperm from the semen,has been shown to be beneficial.The aim of the semen processing technique has been to remove seminal plasma and facilitate capacitation.Additionally,the presence of leukocytes,bacteria,and dead spermatozoa has been shown to be detrimental as it may cause oxidative stress that has an adverse effect on oocyte fertilization and embryo development.Hence,removal of leukocytes,bacteria,and dead spermatozoa is an important step of sperm processing for assisted reproduction.Currently,several sperm processing techniques have been evolved and optimized in the field of assisted reproduction.The requirements for in vitro fertilization(IVF),intracytoplasmic sperm injection(ICSI),and testicular sperm extraction(TESE)are different than those of intrauterine insemination(IUI).The yield of as many motile,morphologically normal sperm as possible is a prerequisite for the success of IVF insemination procedure.In ICSI,where injection of a single spermatozoon into the oocyte is performed by the embryologist,sperm selection techniques play a crucial role in the ICSI procedure.Finally,sperm retrieval in TESE samples with very low number of sperm may be challenging and requires extra care during sample processing.Additionally,sperm cryopreservation is necessary in TESE cases in order to avoid multiple biopsies.
基金the support the National Natural Science Foundation of China(5210440)S&T Program of Hebei(23311501D)Program of HBIS Group under HG2023222。
文摘In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by ion morphology pretreatme nt and solvent extraction.An acidic V(Ⅴ)/W(Ⅵ)solution was obtained using the me mbrane electrolysis method without adding any other chemical reagents.In addition,Na was recovered in the form of NaOH by product,avoiding the generation of Na containing wastewater.The electrolysis parameters were investigated,the lowest power consumption of 3063 kW·h·t^(-1)NaOH was obtained at a current density of 125 A·m^(-2)and an initial NaOH concentration of 2 mol·L^(-1).After electrolysis,oxalic acid was added to the acidic V/W containing solution,converting V(Ⅴ)negative ion to V(Ⅳ)positive ion.Since W(Ⅵ)ion state remained in negative form,the generation of heteropolyacid ions(W_(x)V_(y)O_(z)^(n-))was prevented.It was found that under the condition of oxalic acid addition/theoretical consumption 1.2 and reaction temperature 75℃,100%V(Ⅴ)was co nverted to V(Ⅳ4).Using 10%N263+10%noctanol+80%sulfonated kerosene as extractant,the highest W(Ⅵ)/V(Ⅳ)separation coefficient of 7559.76was obtained at pH=1.8,O:A ratio=1:1 and extraction time 15 min.With 2 mol·L^(-1)NaOH as stripping reagent,the W stripping efficiency reached 98.50%at O:A ratio=2:1 after 4-stages of stripping.The enrichment of V remained in the solution was realized using P204 as extractant and 20%(mass)H_(2)SO_(4)as stripping reagent.The parameters of extraction/stripping process were investigated,using 10%P204+10%TBP+80%sulfonated kerosene as extractant,the V extraction efficiency reached 97.50%at O:A ratio=1:2after 4 stages of extraction.Using 20%H_(2)SO_(4)as the stripping reagent,the V stripping efficiency was 98.30%at an O:A ratio of 4:1 after five stage s of stripping.After the entire process,a high-purity VOSO_(4)and Na_(2)WO_(4)product solutions were obtained with V/W recovery efficiency 95.84%/98.50%,separately.This study examined a more effective and cleaner method for separating V/W/Na in Na_(2)WO_(4)/NaVO_(3)solution,which may serve as a reference for the separation and recovery of V/W/Na in waste SCR catalysts.
文摘This review paper was prepared at Department of Zoology, University of Gujrat, Pakistan during 2014-2015. The data for the two decades, DNA Extraction from Insects by Using Different Techniques was compiled through a thorough review of many research articles published in various journals of international repute. Insects are very important economically and ecologically for human due to their various roles, as pests, decomposer in nutrition cycle, vector for the transmission of certain diseases and a source of medically and economically important products. To identify insect, and for research on their role, different molecular techniques are used. For each molecular technique, high quality DNA is required, which is extracted from the insects by different techniques. The selection of DNA extraction technique is depended upon specimen under study, time required for extraction, economical stander of technique due to reagents and equipment used for extraction and most importantly extracted DNA quality. In this paper, most frequently used techniques for DNA extraction from insect with different size and condition are outlined. This paper is only a guide for these techniques and we describe them briefly.
基金financially supported by the National Natural Science Foundation of China (52174336)the Natural Science Foundation of Shandong Province (ZR2021MB051)。
文摘In recent years,with the rapid developme nt of the econo my and society,pollution of valuable metal ions in wastewater has become a major challenge to environmental sustainability.In order to solve the pollution caused by metal ions,researchers have conducted continuous re searches and explored various re mediation methods.Crown ether has attracted great attention because of its ionic radius and cavity size matching well with metal ions,which makes it have the ability to selectively complex metal ions.This unique property enables the directed removal and recovery of metal ions and makes crown ethers increasingly popular in extraction and separation processes.In this paper,the research progress of crown ethers in the extraction and separation of valuable metal ions was reviewed,with emphasis on the principles,extraction systems and the key factors affecting the extraction process.This study can provide some technical support for the application of separation and extraction of valuable metal ions by crown ether.
文摘[Objectives]This study was conducted to investigate the extraction technology of celastrol from Celastrus orbiculatus Thunb.[Methods]Solvent ultrasonic extraction was selected,and with the content of celastrol as the evaluation index,the effects of different solvents,extraction time,temperatures and material-to-liquid ratios on the extraction rate of celastrol were investigated by single factor and orthogonal experiments.[Results]The optimal extraction conditions were as follows:a solvent ratio of petroleum ether to ethyl acetate at 1∶1,a ratio of solvent to material at 10∶1(v/w),extraction time of 30 min,and an extraction temperature at 30℃.[Conclusions]This method has high extraction rate,and is simple and feasible.
基金Supported by the National Natural Science Foundation of China(41101066)the China Postdoctoral Science Foundation Funded Project(2013M532094)
文摘Hydrograph separation is a fundamental catchment descriptor,revealing information about sources of water in runoff generation processes. The water isotopes are ideal tracers in studying hydrological processes since the isotope fractionation produces a natural labeling effect within the hydrologic cycle. The water isotope technique has become one of effective means for investigating complex hydrologic system on a catchment scale. This paper reviews the progress on the use of stable water isotope techniques in catchment hydrograph separation in last decades. Also,the isotope mixing model for hydrograph separation and its uncertainties are explained in detail. In future research,there are three hot issues in the use of isotopic hydrograph separation（ IHS） ： integrating new approaches into IHS,calibration and verification of IHS model and IHS application in large river basins.
