Background Although 15 mA transcranial alternating current stimulation(tACS)has a therapeutic effect on depression,the activations of brain structures in humans accounting for this tACS configuration remain largely un...Background Although 15 mA transcranial alternating current stimulation(tACS)has a therapeutic effect on depression,the activations of brain structures in humans accounting for this tACS configuration remain largely unknown.Aims To investigate which intracranial brain structures are engaged in the tACS at 77.5 Hz and 15 mA,delivered via the forehead and the mastoid electrodes in the human brain.Methods Actual human head models were built using the magnetic resonance imagings of eight outpatient volunteers with drug-naïve,first-episode major depressive disorder and then used to perform the electric field distributions with SimNIBS software.Results The electric field distributions of the sagittal,coronal and axial planes showed that the bilateral frontal lobes,bilateral temporal lobes,hippocampus,cingulate,hypothalamus,thalamus,amygdala,cerebellum and brainstem were visibly stimulated by the 15 mA tACS procedure.Conclusions Brain-wide activation,including the cortex,subcortical structures,cerebellum and brainstem,is involved in the 15 mA tACS intervention for first-episode major depressive disorder.Our results indicate that the simultaneous involvement of multiple brain regions is a possible mechanism for its effectiveness in reducing depressive symptoms.展开更多
Totheeditor:Major depressive disorder(MDD)is a principal cause of disability worldwide and is often associated with high morbidity and mortality rates.Although there are several therapies available for the treatment o...Totheeditor:Major depressive disorder(MDD)is a principal cause of disability worldwide and is often associated with high morbidity and mortality rates.Although there are several therapies available for the treatment of depression,about one-third of patients with MMD will not respond to two or more antidepressant drugs with different mechanisms;the patients are then referred to as having treatment-resistant depression(TRD).Patients with TRD have a poorer quality of life,greater economic burden and increased suicidal behaviours.Therefore,new antidepressant treatments that are effective,safe,long-lasting and tolerable are needed.Ketamine infusion,intranasal esketamine and transcranial magnetic stimulation(TMS)have been used to treat early stage TRD.’A recent review suggests that electroconvulsive therapy(ECT)may be superior to ketamine for reducing depression severity in the acute treatment of TRD.展开更多
The transesterification of palm oil and methanol catalyzed by Br?nsted acidic ionic liquids was investigated. Four eco-friendly Br?nsted acidic ionic liquids were prepared and their structures were characterized by NM...The transesterification of palm oil and methanol catalyzed by Br?nsted acidic ionic liquids was investigated. Four eco-friendly Br?nsted acidic ionic liquids were prepared and their structures were characterized by NMR, FT-IR and TG–DTG. The results demonstrated that [CyN_(1,1)PrSO_3H][p-TSA] was more efficient than the other ionic liquids and chosen as catalyst for further research. The influences of various reaction parameters on the conversion of palm oil to biodiesel were performed, and the orthogonal test was investigated to seek the optimum reaction conditions, which were illustrated as follows: methanol to oil mole ratio of 24:1, catalyst dosage of 3.0 wt% of oil, reaction temperature of 120 °C, reaction time of 150 min, and the biodiesel yield achieved 98.4%. In addition, kinetic study was established for the conversion process, with activation energy and preexponential factor of 122.93 k J·mol^(-1) and 1.83 × 10^(15), respectively. Meanwhile, seven-time recycling runs of ionic liquid were completed with ignorable loss of its catalyst activity. The refined biodiesel met the biodiesel standard EN 14214.展开更多
Objective:As a member of the peptidyl arginine deiminase(PAD)family,PADI3 is weakly expressed in colon cancer tissues and highly expressed in adjacent colon cancer tissues.However,the role of PADI3 in colon cancer is ...Objective:As a member of the peptidyl arginine deiminase(PAD)family,PADI3 is weakly expressed in colon cancer tissues and highly expressed in adjacent colon cancer tissues.However,the role of PADI3 in colon cancer is unclear.In this study,we investigated the function and molecular mechanism of PADI3 in colon cancer tumorigenesis.Methods:Western blot and real-time PCR were used to detect the expression levels of several genes.CCK-8,flow cytometry(FCM)and colony formation assays were used to examine cell proliferation,the cell cycle and colony formation ability.RNAsequencing analysis was used to study the molecular mechanism of PADI3 in tumorigenesis.A truncation mutation experiment was performed to determine the key functional domain of PADI3.Results:PADI3 overexpression inhibited cell proliferation and colony formation and led to G1 phase arrest in both HCT116(originating from primary colon cancer)and LoVo(originating from metastatic tumor nodules of colon cancer)cells.PADI3-expressing HCT116 cells had a lower tumor formation rate and produced smaller tumors than control cells.PADI3 significantly decreased Sirtuin2(Sirt2)and Snail expression and AKT phosphorylation and increased p21 expression,and Sirt2 overexpression partly reversed the effects induced by PADI3 overexpression.Immunocytochemistry showed that PADI3 is mainly localized in the cytoplasm.Truncation mutation experiments showed that the C-domain is the key domain involved in the antitumor activity of PADI3.Conclusions:PADI3 suppresses Snail expression and AKT phosphorylation and promotes p21 expression by downregulating Sirt2 expression in the cytoplasm,and the C-domain is the key domain for its antitumor activity.展开更多
Converting polyethylene terephthalate(PET)wastes to its monomer and valuable chemicals via ecofriendly chemical method is still a challenge task.Previously,phase transfer catalysts used for alkaline hydrolysis were so...Converting polyethylene terephthalate(PET)wastes to its monomer and valuable chemicals via ecofriendly chemical method is still a challenge task.Previously,phase transfer catalysts used for alkaline hydrolysis were soluble in reaction media and hardly separated after reaction.Here,we reported several pH-responsive catalysts combined alkyl quaternary ammonium units with heteropolyacid anion for achieving stepwise product/catalyst separation and catalyst recycling.The properties of homogeneous/heterogeneous transfer behavior allow catalyst to be easily separated from reaction media by adjusting of pH value.Among them,[C_(16)H_(33)N(CH_(3))_(3)]_(3)PW_(12)O_(40)(abbreviated as[CTA]_(3)PW)exhibits the highest activity and the most suitable pH responsive values.Such a pH triggered switchable catalytic system not only shows good performance for depolymerization of pure PET,but also some real PET wastes such as coloured trays and PE/PET complex films could be completely degraded into terephthalic acid.Additionally,the reaction kinetics and activation energy of PET alkaline hydrolysis also studied with and without pH-responsive[CTA]_(3)PW.展开更多
Producing 2-ethyl-1-hexyl thioglycolate(ETE)via esterification reaction with thioglycolic acid(TGA)aqueous solution as raw material by reactive-separation coupling technology is a promising process intensification met...Producing 2-ethyl-1-hexyl thioglycolate(ETE)via esterification reaction with thioglycolic acid(TGA)aqueous solution as raw material by reactive-separation coupling technology is a promising process intensification method.To choose suitable reactive-separation coupling strategy,the kinetic studies of the esterification of TGA with 2-ethyl-1-hexanol(EHL)were carried out in a batch system.The commercial ion exchange resin was employed as an eco-friendly catalyst.The effects of temperature,catalyst concentration and molar ratio were determined.It was interesting to observe that the equilibrium conversion of TGA increased with the increase of catalyst mass fraction due to the adsorption of product water onto resin surface.The activity-based pseudo-homogeneous(PH),Eley-Rideal(ER)and Langmuir-Hinshelwood-Ho ugen-Watson(LHHW)models were used to fit the kinetics data of the resin-catalyzed reaction.The models of ER and LHHW performed better than the PH model.The kinetics of the TGA-self-catalyzed reaction was also determined.An activity-based homogeneous kinetics model could well describe this self-catalyzed reaction.These results would be meaningful to the selection and design of an appropriate reactionseparation strategy for the production of ETE,to realize the process intensification.展开更多
For separating some specific four component mixtures into four products, the four-product dividing wall column(FPDWC) with two partition walls can provide the same utility consumption with the extended Petlyuk configu...For separating some specific four component mixtures into four products, the four-product dividing wall column(FPDWC) with two partition walls can provide the same utility consumption with the extended Petlyuk configuration, although with structure simplicity. However, the reluctance to implement this kind of four product dividing wall column industrially also consists in the two uncontrollable vapor splits associated with it. The vapor split ratios are set at the design stage and might not be the optimal value for changed feed composition, thus minimum energy consumption could not be ensured. In the present work, a sequential iterative optimization approach was initially employed to determine the parameters of cost-effective FPDWC. Then the effect of maintaining the vapor split ratios at their nominal value on the energy penalty was investigated for the FPDWC with two partition walls, in case of feed composition disturbance. The result shows that no more than + 2% above the optimal energy requirements could be ensured for 20% feed composition disturbances, which is encouraging for industrial implementation.展开更多
In this work,we investigate the influence of defect concentration of the diamond substrates on the performance of hydrogen-terminated diamond field-effect transistors by Raman spectra,pulsed I–V characteristics analy...In this work,we investigate the influence of defect concentration of the diamond substrates on the performance of hydrogen-terminated diamond field-effect transistors by Raman spectra,pulsed I–V characteristics analysis,and radio frequency performances measurements.It is found that a sample with higher defect concentration shows larger drain-lag effect and lower large-signal output power density.Defects in the diamond act as traps in the carrier transport and have a considerable influence on the large-signal output power density of diamond field-effect transistors.This work should be helpful for further performance improvement of the microwave power diamond devices.展开更多
[Objectives] The aim was to elucidate the pro-apoptosis mechanism of naphthoquinone derivative 2-octyl sulfoxide-1,4-naphthoquinone(OSNQ) on human colon cancer SW480 cells.[Methods]The cytotoxic effect of OSNQ on colo...[Objectives] The aim was to elucidate the pro-apoptosis mechanism of naphthoquinone derivative 2-octyl sulfoxide-1,4-naphthoquinone(OSNQ) on human colon cancer SW480 cells.[Methods]The cytotoxic effect of OSNQ on colon cancer SW480 cells was detected by MTT colorimetry.The pro-apoptotic effect of OSNQ on human colon cancer SW480 cells was detected by Annexin V-FITC/PI double staining.The changes in expression of apoptosis-related proteins were detected by Western blot.[Results]The results of MTT assay showed that OSNQ had a significant cytotoxic effect on colon cancer SW480 cells.The results of Western blot showed that OSNQ induced the apoptosis in colon cancer SW480 cells through promoting the expression of pro-apoptotic caspase-3 and inhibiting the expression of apoptosis-inhibiting protein Bcl-2.[Conclusions] OSNQ has a significant cytotoxic effect on colon cancer SW480 cells,and it induces the apoptosis of colon cancer SW480 cells by AKT signaling pathway.展开更多
Cytisine(Cyt) is a kind of quinolizidine alkaloids mainly existing in seeds of plants from Laburnum of Leguminosae sp. In recent years, various biological activities of Cyt have been explored gradually, and it has the...Cytisine(Cyt) is a kind of quinolizidine alkaloids mainly existing in seeds of plants from Laburnum of Leguminosae sp. In recent years, various biological activities of Cyt have been explored gradually, and it has the effects of quitting smoking, promoting breathing, analgesia, and anti-cancer. At anti-cancer aspect, Cyt could induce apoptosis of cancer cells, and has been widely applied to inhibit proliferation of multiple tumor cells. At quitting smoking aspect, Cyt could be taken as selective local agonist to decline smokers' dependence on nicotine, and it is expected to be widely used in quitting smoking. At analgesia aspect, Cyt could regulate reflective exciting breathing and has been widely used in anesthesia of patients in clinical operation. In this paper, through consulting and verifying a large number of documents, biological activities of Cyt and its related action mechanisms are summarized, to provide theoretic basis for the development and utilization of Cyt.展开更多
A three-dimensional thermal analysis of GaN HEMTs on diamond substrate is investigated using the finite element method. The diamond substrate thickness, area and shape, transition layer thickness and thermal conductiv...A three-dimensional thermal analysis of GaN HEMTs on diamond substrate is investigated using the finite element method. The diamond substrate thickness, area and shape, transition layer thickness and thermal conductivity of the transition layer are considered and treated appropriately in the numerical simulation. The temperature distribution and heat spreading paths are investigated under different conditions and the results indicate that the existence of the transition layer causes an increase in the channel temperature and the thickness, area and shape of the diamond substrate have certain impacts on the channel temperature too. Channel temperature reduces with increasing diamond substrate thickness and area but with a decreasing trend, which can be explained by the saturation effects of the diamond substrate. The shape of diamond substrate also affects the temperature performance of GaN HEMTs, therefore, to achieve a favorable heat dissipation effect with the settled diamond substrate area, the shape should contain as many isothermal curves as possible when the isothermal gradient is constant. The study of the thermal properties of GaN on diamond substrate is useful for the prediction of heating of high power GaN HEMTs devices and optimal designs of an efficient heat spreader for GaN HEMTs.展开更多
Three-dimensional CuS hierarchical crystals with high catalytic activity had been successfully fabricated using a facile solvothermal process, The CuS microparticles showed different flower-like morphology and good di...Three-dimensional CuS hierarchical crystals with high catalytic activity had been successfully fabricated using a facile solvothermal process, The CuS microparticles showed different flower-like morphology and good dispersion by optimizing reaction conditions. It was found that using N,N-dimethylformamide (DMF) as the solvent reagent in the proper temperature conditions was favorable for the growth of hierarchically structured CuS. The hexagonal flower-like CuS synthesized at 170℃ for 60 min displayed broad-spectrum photocatalytic properties under ultraviolet (UV) and visible irradiation. The as-prepared CuS crystals exhibited good performance to decolorize methylene blue (MB) solution under visible light irradiation. The total organic carbon (TOC) removal of rhodamine B (RhB) solution was nearly 60% after 5 h of the natural sunlight irradiation, and the property was stable after testing over four recycles, demonstrating a potential application in waster water treatment.展开更多
In this paper,we use the Lowner partial order and the star partial order to introduce a new partial order(denoted by"L^(*)")on the set of group matrices,and get some characteristics and properties of the new...In this paper,we use the Lowner partial order and the star partial order to introduce a new partial order(denoted by"L^(*)")on the set of group matrices,and get some characteristics and properties of the new partial order.In particular,we prove that the L*partial order is a special kind of the core partial order and it is equivalent to the star partial order under some conditions.We also illustrate its difference from other partial orders with examples and find out under what conditions it is equivalent to other partial orders.展开更多
Kumquat(Fortunella spp.)is a fruit and ornamental crop worldwide due to the palatable taste and high ornamental value of its fruit.Although Fortunella is classified into the economically important true citrus fruit tr...Kumquat(Fortunella spp.)is a fruit and ornamental crop worldwide due to the palatable taste and high ornamental value of its fruit.Although Fortunella is classified into the economically important true citrus fruit tree group together with Citrus and Poncirus,few studies have been focused on its evolutionary scenario.In this study,analysis of five chloroplast loci and 47 nuclear microsatellites(nSSR)loci from 38 kumquat and 10 citrus accessions revealed the independent phylogeny of Fortunella among citrus taxa,and that Fortunella mainly comprises two populations:CUL,cultivated Fortunella spp.(F.margarita,F.crassifolia and F.japonica);and HK,wild Hong Kong kumquat(Fortunella hindsii).Genomic analysis based on whole-genome SNPs indicated that the allele frequency of both pupations deviated from the neutral selection model,suggesting directional selection was a force driving their evolutions.CUL exhibited lower genomic diversity and higher linkage strength than HK,suggesting artificial selection involved in its origin.A high level of genetic differentiation(Fst=0.364)was detected and obviously asynchronous demographic changes were observed between CUL and HK.Based on these results,a new hypothesis for the speciation of Fortunella is proposed.展开更多
Conventional periodic structures usually have nontunable refractive indices and thus lead to immutable photonic bandgaps. A periodic structure created in an ultracold atoms ensemble by externally controlled light can ...Conventional periodic structures usually have nontunable refractive indices and thus lead to immutable photonic bandgaps. A periodic structure created in an ultracold atoms ensemble by externally controlled light can overcome this disadvantage and enable lots of promising applications. Here, two novel types of optically induced square lattices, i.e., the amplitude and phase lattices, are proposed in an ultracold atoms ensemble by interfering four ordinary plane waves under different parameter conditions. We demonstrate that in the far-field regime, the atomic amplitude lattice with high transmissivity behaves similarly to an ideal pure sinusoidal amplitude lattice, whereas the atomic phase lattices capable of producing phase excursion across a weak probe beam along with high transmissivity remains equally ideal. Moreover, we identify that the quality of Talbot imaging about a phase lattice is greatly improved when compared with an amplitude lattice. Such an atomic lattice could find applications in alloptical switching at the few photons level and paves the way for imaging ultracold atoms or molecules both in the near-field and in the far-field with a nondestructive and lensless approach.展开更多
基金The study was partly funded by the National Natural Science Foundation of China(82371490)the National Key R&D Program of China(2022YFC2503900,2022YFC2503901)+1 种基金Beijing Hundred,Thousand and Ten Thousand Talents Project(2017-CXYF-09)Beijing Health System Leading Talent Grant(2022-02-10).
文摘Background Although 15 mA transcranial alternating current stimulation(tACS)has a therapeutic effect on depression,the activations of brain structures in humans accounting for this tACS configuration remain largely unknown.Aims To investigate which intracranial brain structures are engaged in the tACS at 77.5 Hz and 15 mA,delivered via the forehead and the mastoid electrodes in the human brain.Methods Actual human head models were built using the magnetic resonance imagings of eight outpatient volunteers with drug-naïve,first-episode major depressive disorder and then used to perform the electric field distributions with SimNIBS software.Results The electric field distributions of the sagittal,coronal and axial planes showed that the bilateral frontal lobes,bilateral temporal lobes,hippocampus,cingulate,hypothalamus,thalamus,amygdala,cerebellum and brainstem were visibly stimulated by the 15 mA tACS procedure.Conclusions Brain-wide activation,including the cortex,subcortical structures,cerebellum and brainstem,is involved in the 15 mA tACS intervention for first-episode major depressive disorder.Our results indicate that the simultaneous involvement of multiple brain regions is a possible mechanism for its effectiveness in reducing depressive symptoms.
基金supported by the National Natural Science Foundation of China(82371490)the National Key R&D Program of China(2022YFC2503901,2022YFC2503900)+1 种基金the Beijing Hundred,Thousand,and Ten Thousand Talents Project(2017-CXYF-09)Beijing Health System Leading Talent Grant(2022-02-10).
文摘Totheeditor:Major depressive disorder(MDD)is a principal cause of disability worldwide and is often associated with high morbidity and mortality rates.Although there are several therapies available for the treatment of depression,about one-third of patients with MMD will not respond to two or more antidepressant drugs with different mechanisms;the patients are then referred to as having treatment-resistant depression(TRD).Patients with TRD have a poorer quality of life,greater economic burden and increased suicidal behaviours.Therefore,new antidepressant treatments that are effective,safe,long-lasting and tolerable are needed.Ketamine infusion,intranasal esketamine and transcranial magnetic stimulation(TMS)have been used to treat early stage TRD.’A recent review suggests that electroconvulsive therapy(ECT)may be superior to ketamine for reducing depression severity in the acute treatment of TRD.
基金Supported by the National Natural Science Foundation of China(21576053)the Natural Science Foundation of Fujian Province(2016J01689)the Young Teacher Education Research Foundation of Fujian Province(JAT160056)
文摘The transesterification of palm oil and methanol catalyzed by Br?nsted acidic ionic liquids was investigated. Four eco-friendly Br?nsted acidic ionic liquids were prepared and their structures were characterized by NMR, FT-IR and TG–DTG. The results demonstrated that [CyN_(1,1)PrSO_3H][p-TSA] was more efficient than the other ionic liquids and chosen as catalyst for further research. The influences of various reaction parameters on the conversion of palm oil to biodiesel were performed, and the orthogonal test was investigated to seek the optimum reaction conditions, which were illustrated as follows: methanol to oil mole ratio of 24:1, catalyst dosage of 3.0 wt% of oil, reaction temperature of 120 °C, reaction time of 150 min, and the biodiesel yield achieved 98.4%. In addition, kinetic study was established for the conversion process, with activation energy and preexponential factor of 122.93 k J·mol^(-1) and 1.83 × 10^(15), respectively. Meanwhile, seven-time recycling runs of ionic liquid were completed with ignorable loss of its catalyst activity. The refined biodiesel met the biodiesel standard EN 14214.
基金supported by the National Natural Science Foundation for the Youth of China (Grant No. 81802422 and 81702440)the Shandong Provincial Key R & D Program (Nos. 2019GSF108115, 2017GSF218102)+2 种基金Jinan Science and Technology Development Program (Nos. 201907116)Shandong Science and Technology Development Plan (Grant No. 2017GFS18195)Shandong Traditional Chinese Medicine Science and Technology Development Programs (Grant No. 2017-173)
文摘Objective:As a member of the peptidyl arginine deiminase(PAD)family,PADI3 is weakly expressed in colon cancer tissues and highly expressed in adjacent colon cancer tissues.However,the role of PADI3 in colon cancer is unclear.In this study,we investigated the function and molecular mechanism of PADI3 in colon cancer tumorigenesis.Methods:Western blot and real-time PCR were used to detect the expression levels of several genes.CCK-8,flow cytometry(FCM)and colony formation assays were used to examine cell proliferation,the cell cycle and colony formation ability.RNAsequencing analysis was used to study the molecular mechanism of PADI3 in tumorigenesis.A truncation mutation experiment was performed to determine the key functional domain of PADI3.Results:PADI3 overexpression inhibited cell proliferation and colony formation and led to G1 phase arrest in both HCT116(originating from primary colon cancer)and LoVo(originating from metastatic tumor nodules of colon cancer)cells.PADI3-expressing HCT116 cells had a lower tumor formation rate and produced smaller tumors than control cells.PADI3 significantly decreased Sirtuin2(Sirt2)and Snail expression and AKT phosphorylation and increased p21 expression,and Sirt2 overexpression partly reversed the effects induced by PADI3 overexpression.Immunocytochemistry showed that PADI3 is mainly localized in the cytoplasm.Truncation mutation experiments showed that the C-domain is the key domain involved in the antitumor activity of PADI3.Conclusions:PADI3 suppresses Snail expression and AKT phosphorylation and promotes p21 expression by downregulating Sirt2 expression in the cytoplasm,and the C-domain is the key domain for its antitumor activity.
基金the support of the National Natural Science Foundation of China(22005276)。
文摘Converting polyethylene terephthalate(PET)wastes to its monomer and valuable chemicals via ecofriendly chemical method is still a challenge task.Previously,phase transfer catalysts used for alkaline hydrolysis were soluble in reaction media and hardly separated after reaction.Here,we reported several pH-responsive catalysts combined alkyl quaternary ammonium units with heteropolyacid anion for achieving stepwise product/catalyst separation and catalyst recycling.The properties of homogeneous/heterogeneous transfer behavior allow catalyst to be easily separated from reaction media by adjusting of pH value.Among them,[C_(16)H_(33)N(CH_(3))_(3)]_(3)PW_(12)O_(40)(abbreviated as[CTA]_(3)PW)exhibits the highest activity and the most suitable pH responsive values.Such a pH triggered switchable catalytic system not only shows good performance for depolymerization of pure PET,but also some real PET wastes such as coloured trays and PE/PET complex films could be completely degraded into terephthalic acid.Additionally,the reaction kinetics and activation energy of PET alkaline hydrolysis also studied with and without pH-responsive[CTA]_(3)PW.
基金the financial support for this work from the National Natural Science Foundation of China(No.21706034)the Guiding Project of Fujian Province(No.2018H0016)+1 种基金the Open Foundation of State Key Laboratory of Chemical Engineering(No.SKL-ChE-18B02)the Integration of Industry,Education and Research of Fujian Province(No.2018Y4008).
文摘Producing 2-ethyl-1-hexyl thioglycolate(ETE)via esterification reaction with thioglycolic acid(TGA)aqueous solution as raw material by reactive-separation coupling technology is a promising process intensification method.To choose suitable reactive-separation coupling strategy,the kinetic studies of the esterification of TGA with 2-ethyl-1-hexanol(EHL)were carried out in a batch system.The commercial ion exchange resin was employed as an eco-friendly catalyst.The effects of temperature,catalyst concentration and molar ratio were determined.It was interesting to observe that the equilibrium conversion of TGA increased with the increase of catalyst mass fraction due to the adsorption of product water onto resin surface.The activity-based pseudo-homogeneous(PH),Eley-Rideal(ER)and Langmuir-Hinshelwood-Ho ugen-Watson(LHHW)models were used to fit the kinetics data of the resin-catalyzed reaction.The models of ER and LHHW performed better than the PH model.The kinetics of the TGA-self-catalyzed reaction was also determined.An activity-based homogeneous kinetics model could well describe this self-catalyzed reaction.These results would be meaningful to the selection and design of an appropriate reactionseparation strategy for the production of ETE,to realize the process intensification.
基金Supported by Open Research Project of State Key Laboratory of Chemical Engineering(SKL-ChE-16B06)Yangtze Scholars and Innovative Research Team in Chinese University(IRT-17R81)
文摘For separating some specific four component mixtures into four products, the four-product dividing wall column(FPDWC) with two partition walls can provide the same utility consumption with the extended Petlyuk configuration, although with structure simplicity. However, the reluctance to implement this kind of four product dividing wall column industrially also consists in the two uncontrollable vapor splits associated with it. The vapor split ratios are set at the design stage and might not be the optimal value for changed feed composition, thus minimum energy consumption could not be ensured. In the present work, a sequential iterative optimization approach was initially employed to determine the parameters of cost-effective FPDWC. Then the effect of maintaining the vapor split ratios at their nominal value on the energy penalty was investigated for the FPDWC with two partition walls, in case of feed composition disturbance. The result shows that no more than + 2% above the optimal energy requirements could be ensured for 20% feed composition disturbances, which is encouraging for industrial implementation.
基金This work was supported by the National Natural Science Foundation of China(Grant No.51702296)Excellent Youth Foundation of Hebei Scientific Committee(Grant No.F2019516002).
文摘In this work,we investigate the influence of defect concentration of the diamond substrates on the performance of hydrogen-terminated diamond field-effect transistors by Raman spectra,pulsed I–V characteristics analysis,and radio frequency performances measurements.It is found that a sample with higher defect concentration shows larger drain-lag effect and lower large-signal output power density.Defects in the diamond act as traps in the carrier transport and have a considerable influence on the large-signal output power density of diamond field-effect transistors.This work should be helpful for further performance improvement of the microwave power diamond devices.
基金Supported by the Multigrain Production and Processing Characteristic Discipline Construction ProjectPostdoctoral Scientific Research Foundation of Heilongjiang Province of China(LBH-Q13132)
文摘[Objectives] The aim was to elucidate the pro-apoptosis mechanism of naphthoquinone derivative 2-octyl sulfoxide-1,4-naphthoquinone(OSNQ) on human colon cancer SW480 cells.[Methods]The cytotoxic effect of OSNQ on colon cancer SW480 cells was detected by MTT colorimetry.The pro-apoptotic effect of OSNQ on human colon cancer SW480 cells was detected by Annexin V-FITC/PI double staining.The changes in expression of apoptosis-related proteins were detected by Western blot.[Results]The results of MTT assay showed that OSNQ had a significant cytotoxic effect on colon cancer SW480 cells.The results of Western blot showed that OSNQ induced the apoptosis in colon cancer SW480 cells through promoting the expression of pro-apoptotic caspase-3 and inhibiting the expression of apoptosis-inhibiting protein Bcl-2.[Conclusions] OSNQ has a significant cytotoxic effect on colon cancer SW480 cells,and it induces the apoptosis of colon cancer SW480 cells by AKT signaling pathway.
基金Supported by the Multigrain Production and Processing Characteristic Discipline Construction Projectthe Postdoctoral Scientific Research Foundation of Heilongjiang Province of China(LBH-Q13132)the National Key Research and Development Plan(2017YFD0401203)
文摘Cytisine(Cyt) is a kind of quinolizidine alkaloids mainly existing in seeds of plants from Laburnum of Leguminosae sp. In recent years, various biological activities of Cyt have been explored gradually, and it has the effects of quitting smoking, promoting breathing, analgesia, and anti-cancer. At anti-cancer aspect, Cyt could induce apoptosis of cancer cells, and has been widely applied to inhibit proliferation of multiple tumor cells. At quitting smoking aspect, Cyt could be taken as selective local agonist to decline smokers' dependence on nicotine, and it is expected to be widely used in quitting smoking. At analgesia aspect, Cyt could regulate reflective exciting breathing and has been widely used in anesthesia of patients in clinical operation. In this paper, through consulting and verifying a large number of documents, biological activities of Cyt and its related action mechanisms are summarized, to provide theoretic basis for the development and utilization of Cyt.
基金Project supported by the National Natural Science Foundation of China(Nos.60876042,61176018,61627812)
文摘A three-dimensional thermal analysis of GaN HEMTs on diamond substrate is investigated using the finite element method. The diamond substrate thickness, area and shape, transition layer thickness and thermal conductivity of the transition layer are considered and treated appropriately in the numerical simulation. The temperature distribution and heat spreading paths are investigated under different conditions and the results indicate that the existence of the transition layer causes an increase in the channel temperature and the thickness, area and shape of the diamond substrate have certain impacts on the channel temperature too. Channel temperature reduces with increasing diamond substrate thickness and area but with a decreasing trend, which can be explained by the saturation effects of the diamond substrate. The shape of diamond substrate also affects the temperature performance of GaN HEMTs, therefore, to achieve a favorable heat dissipation effect with the settled diamond substrate area, the shape should contain as many isothermal curves as possible when the isothermal gradient is constant. The study of the thermal properties of GaN on diamond substrate is useful for the prediction of heating of high power GaN HEMTs devices and optimal designs of an efficient heat spreader for GaN HEMTs.
基金We are grateful for the financial support from the National Natural Science Foundation of China (Grant No. 51202156).
文摘Three-dimensional CuS hierarchical crystals with high catalytic activity had been successfully fabricated using a facile solvothermal process, The CuS microparticles showed different flower-like morphology and good dispersion by optimizing reaction conditions. It was found that using N,N-dimethylformamide (DMF) as the solvent reagent in the proper temperature conditions was favorable for the growth of hierarchically structured CuS. The hexagonal flower-like CuS synthesized at 170℃ for 60 min displayed broad-spectrum photocatalytic properties under ultraviolet (UV) and visible irradiation. The as-prepared CuS crystals exhibited good performance to decolorize methylene blue (MB) solution under visible light irradiation. The total organic carbon (TOC) removal of rhodamine B (RhB) solution was nearly 60% after 5 h of the natural sunlight irradiation, and the property was stable after testing over four recycles, demonstrating a potential application in waster water treatment.
基金The work was supported by the Research Fund Project of Guangxi University for Nationalities(No.2019KJQD03)Guangxi Natural Science Foundation(No.2018GXNSFDA281023)+2 种基金the National Natural Science Foundation of China(No.12061015)the Special Fund for Bagui Scholars of Guangxi(No.2016A17)the Education Innovation Program for 2019 Graduate Students(No.gxun-chxzs 2019026).
文摘In this paper,we use the Lowner partial order and the star partial order to introduce a new partial order(denoted by"L^(*)")on the set of group matrices,and get some characteristics and properties of the new partial order.In particular,we prove that the L*partial order is a special kind of the core partial order and it is equivalent to the star partial order under some conditions.We also illustrate its difference from other partial orders with examples and find out under what conditions it is equivalent to other partial orders.
基金funded by the National Key Research and Development Program of China(2018YFD1000106)the National Natural Science Foundation of China(31630065)Special Project for External Science and Technology Cooperation of Science and Technology Department of Yunnan Province(202003AD150014)。
文摘Kumquat(Fortunella spp.)is a fruit and ornamental crop worldwide due to the palatable taste and high ornamental value of its fruit.Although Fortunella is classified into the economically important true citrus fruit tree group together with Citrus and Poncirus,few studies have been focused on its evolutionary scenario.In this study,analysis of five chloroplast loci and 47 nuclear microsatellites(nSSR)loci from 38 kumquat and 10 citrus accessions revealed the independent phylogeny of Fortunella among citrus taxa,and that Fortunella mainly comprises two populations:CUL,cultivated Fortunella spp.(F.margarita,F.crassifolia and F.japonica);and HK,wild Hong Kong kumquat(Fortunella hindsii).Genomic analysis based on whole-genome SNPs indicated that the allele frequency of both pupations deviated from the neutral selection model,suggesting directional selection was a force driving their evolutions.CUL exhibited lower genomic diversity and higher linkage strength than HK,suggesting artificial selection involved in its origin.A high level of genetic differentiation(Fst=0.364)was detected and obviously asynchronous demographic changes were observed between CUL and HK.Based on these results,a new hypothesis for the speciation of Fortunella is proposed.
基金National Natural Science Foundation of China(NSFC)(61605155,61627812)Fundamental Research Funds for the Central Universities
文摘Conventional periodic structures usually have nontunable refractive indices and thus lead to immutable photonic bandgaps. A periodic structure created in an ultracold atoms ensemble by externally controlled light can overcome this disadvantage and enable lots of promising applications. Here, two novel types of optically induced square lattices, i.e., the amplitude and phase lattices, are proposed in an ultracold atoms ensemble by interfering four ordinary plane waves under different parameter conditions. We demonstrate that in the far-field regime, the atomic amplitude lattice with high transmissivity behaves similarly to an ideal pure sinusoidal amplitude lattice, whereas the atomic phase lattices capable of producing phase excursion across a weak probe beam along with high transmissivity remains equally ideal. Moreover, we identify that the quality of Talbot imaging about a phase lattice is greatly improved when compared with an amplitude lattice. Such an atomic lattice could find applications in alloptical switching at the few photons level and paves the way for imaging ultracold atoms or molecules both in the near-field and in the far-field with a nondestructive and lensless approach.