On the basis of the analysis of the process of treating low concentrations of sulfur dioxide （SO2） gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects...On the basis of the analysis of the process of treating low concentrations of sulfur dioxide （SO2） gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects of internal diffusion, cell concentration, and production yield of microorganisms but ignoring the effect of external diffusion. The results obtained from the model simulation show that this model can indicate the influence of the process factors, Cin, η μmax, Cx, A, h, Kin, and Q, on the removal of SO2 and that the prediction of the results by this model is also satisfactory. This kinetic model can also provide some very important indications regarding the preparation of immobilized microorganisms, selection and domestication of proper species of microorganisms, as well as the design of bioreactors.展开更多
BACKGROUND： Recent studies have demonstrated that astrocyte dysfunction plays a central role in inhibiting epileptic seizures and that regulation of astrocyte function may be a new target for treatment of epilepsy. O...BACKGROUND： Recent studies have demonstrated that astrocyte dysfunction plays a central role in inhibiting epileptic seizures and that regulation of astrocyte function may be a new target for treatment of epilepsy. OBJECTIVE： To observe the effects of Ganoderma lucidum spore powder （GLSP） on astrocyte morphology and glutamine synthetase （COS） activity in the hippocampal region of epileptic rats. DESIGN, TIME AND SETTING： A randomized, controlled animal experiment was performed at the Function Laboratory, College of Basic Medicine, Jiamusi University between October and December 2006. MATERIALS： A total of 30 Sprague Dawley （SD） rats were randomized to three groups （n = 10）： control, model, and GLSP. GLSP was sourced from Jiamusi Wild Ganoderma Lucidum Planting Base and prepared to 30 g/L with physiological saline before use. Pentylenetetrazol （PTZ） （10 g/L） was provided by Sigma Company, USA. METHODS： The control group received intraperitoneal （i.p.） and intragastric （i.g.） physiological saline. Following epilepsy induction by i.p. administration of PTZ （35 mg/kg）, rats from the mode/and GLSP groups were ig injected with physiological saline and GLSP （300 mg/kg）, respectively. Each compound was administered once per day, for a total of 28 successive days. Epileptic seizure convulsions were graded 0-5. A higher grade indicated more severe epilepsy. Only those rats showing stage 2 or higher convulsions at least 5 times successively were included in further experiments. MAIN OUTCOME MEASURES： Immediately alter injection, seizure activity was monitored for 30 minutes to determine the latent period and seizure duration; simultaneously, astrocyte numbers and GS activity in the hippocampal region of rats with epilepsy were detected by immunohistochemistry. RESULTS： All 30 rats were included in the final analysis. On day 28, following PTZ administration epileptic seizures were not found in the control group. In the GLSP group, rats exhibited rhythmic head nodding or facial spasms, and the latent period was significantly longer than that of the model group （P 〈 0.05）. In the model group, the majority of rats exhibited myoclonus or generalized convulsions, and epileptic seizure duration was slightly （but not significantly） longer than that in the GLSP group （P 〉 0.05）. Within 2-3 minutes of PTZ injection, the model group exhibited grade 4 or 5 epileptic seizures, and the GLSP group mostly showed grade 2 or 3, and occasionally grade 4 or 5, epileptic seizures. All rats recovered within 30 minutes. The model group exhibited significantly increased astrocytes （P 〈 0.05）, with thicker cellular processes and a higher number of cellular processes, and significantly decreased GS activity （P 〈 0.05） tban the control group. The astrocyte count was significantly decreased but GS activity was significantly increased in the GLSP group when compared with the model group （P 〈 0.05）; however, astrocyte appearance was similar in both groups （P 〈 0.05）. CONCLUSION： GLSP can effectively inhibit astrocyte numbers and elevate GS activity in the hippocampal region of rats with epilepsy, thereby reducing epileptic seizures.展开更多
C_(4)F_(7)N is considered to be the most potential alternative gas for SF_(6).However,harmful decomposition by-products generated by the discharge or overheating faults will pose threat to safe operation and service l...C_(4)F_(7)N is considered to be the most potential alternative gas for SF_(6).However,harmful decomposition by-products generated by the discharge or overheating faults will pose threat to safe operation and service life of gas insulated equipment(GIE).Herein,we investigated the adsorption performance ofγ-Al_(2)O_(3)on C_(4)F_(7)N and its decomposition products to evaluate the possibility of using it as by-products adsorbent or exhaust treatment material.It is found thatγ-Al_(2)O_(3)demonstrates superior adsorption capacity for CF_(4),C_(2)F_(6),C_(3)F_(8),C_(3)F_(6),C_(2)F_(4),and keeps stable after the interaction.The first-principles calculation infers thatγ-Al_(2)O_(3)has stronger interaction with C_(4)F_(7)N,C_(3)F_(6)and C_(3)F_(8)than that of C_(2)F_(4),C_(2)F_(6)and CF_(4).There exists obvious charge transfer between C_(4)F_(7)N andγ-Al_(2)O_(3),which belongs to chemisorption.The interaction between F 2p orbital and C=Cπorbital determines the gas-solid adsorption performance.The desorption properties were also explored and the recovery time was in order of CF_(4)<C_(2)F_(6)<C_(2)F_(4)<C_(3)F_(8)<C_(4)F_(7)N<C_(3)F_(6).Overall,theγ-Al_(2)O_(3)is inappropriate to be used as the adsorbent for decomposition by-products of C_(4)F_(7)N gas mixture-based GIE,while it can be used as exhaust treatment material for C_(4)F_(7)N wasted gas.展开更多
Let u={u(t,x);(t,x)∈R_(+)×R}be the solution to a linear stochastic heat equation driven by a Gaussian noise,which is a Brownian motion in time and a fractional Brownian motion in space with Hurst parameter H∈(0...Let u={u(t,x);(t,x)∈R_(+)×R}be the solution to a linear stochastic heat equation driven by a Gaussian noise,which is a Brownian motion in time and a fractional Brownian motion in space with Hurst parameter H∈(0,1).For any given x∈R(resp.,t∈R_(+)),we show a decomposition of the stochastic process t(→)u(t,x)(resp.,x(→)u(t,x))as the sum of a fractional Brownian motion with Hurst parameter H/2(resp.,H)and a stochastic process with C^(∞)-continuous trajectories.Some applications of those decompositions are discussed.展开更多
基金This project was supported by the National Natural Science Foundation of China (2003E0027M)
文摘On the basis of the analysis of the process of treating low concentrations of sulfur dioxide （SO2） gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects of internal diffusion, cell concentration, and production yield of microorganisms but ignoring the effect of external diffusion. The results obtained from the model simulation show that this model can indicate the influence of the process factors, Cin, η μmax, Cx, A, h, Kin, and Q, on the removal of SO2 and that the prediction of the results by this model is also satisfactory. This kinetic model can also provide some very important indications regarding the preparation of immobilized microorganisms, selection and domestication of proper species of microorganisms, as well as the design of bioreactors.
基金Innovation Scientific Research Foundation for Postgraduates in Heilongjiang Province, No. YJSCX2007-0082HLJScience and Technology Research Foundation of Heilongjiang Provincial Department of Education, No. 11521276Natural Science Foundation of Heilongjiang Province, No.D200803
文摘BACKGROUND： Recent studies have demonstrated that astrocyte dysfunction plays a central role in inhibiting epileptic seizures and that regulation of astrocyte function may be a new target for treatment of epilepsy. OBJECTIVE： To observe the effects of Ganoderma lucidum spore powder （GLSP） on astrocyte morphology and glutamine synthetase （COS） activity in the hippocampal region of epileptic rats. DESIGN, TIME AND SETTING： A randomized, controlled animal experiment was performed at the Function Laboratory, College of Basic Medicine, Jiamusi University between October and December 2006. MATERIALS： A total of 30 Sprague Dawley （SD） rats were randomized to three groups （n = 10）： control, model, and GLSP. GLSP was sourced from Jiamusi Wild Ganoderma Lucidum Planting Base and prepared to 30 g/L with physiological saline before use. Pentylenetetrazol （PTZ） （10 g/L） was provided by Sigma Company, USA. METHODS： The control group received intraperitoneal （i.p.） and intragastric （i.g.） physiological saline. Following epilepsy induction by i.p. administration of PTZ （35 mg/kg）, rats from the mode/and GLSP groups were ig injected with physiological saline and GLSP （300 mg/kg）, respectively. Each compound was administered once per day, for a total of 28 successive days. Epileptic seizure convulsions were graded 0-5. A higher grade indicated more severe epilepsy. Only those rats showing stage 2 or higher convulsions at least 5 times successively were included in further experiments. MAIN OUTCOME MEASURES： Immediately alter injection, seizure activity was monitored for 30 minutes to determine the latent period and seizure duration; simultaneously, astrocyte numbers and GS activity in the hippocampal region of rats with epilepsy were detected by immunohistochemistry. RESULTS： All 30 rats were included in the final analysis. On day 28, following PTZ administration epileptic seizures were not found in the control group. In the GLSP group, rats exhibited rhythmic head nodding or facial spasms, and the latent period was significantly longer than that of the model group （P 〈 0.05）. In the model group, the majority of rats exhibited myoclonus or generalized convulsions, and epileptic seizure duration was slightly （but not significantly） longer than that in the GLSP group （P 〉 0.05）. Within 2-3 minutes of PTZ injection, the model group exhibited grade 4 or 5 epileptic seizures, and the GLSP group mostly showed grade 2 or 3, and occasionally grade 4 or 5, epileptic seizures. All rats recovered within 30 minutes. The model group exhibited significantly increased astrocytes （P 〈 0.05）, with thicker cellular processes and a higher number of cellular processes, and significantly decreased GS activity （P 〈 0.05） tban the control group. The astrocyte count was significantly decreased but GS activity was significantly increased in the GLSP group when compared with the model group （P 〈 0.05）; however, astrocyte appearance was similar in both groups （P 〈 0.05）. CONCLUSION： GLSP can effectively inhibit astrocyte numbers and elevate GS activity in the hippocampal region of rats with epilepsy, thereby reducing epileptic seizures.
基金National Natural Science Foundation of China,Grant/Award Number:51977159The fellowship of China Postdoctoral Science Foundation,Grant/Award Number:2022M712446。
文摘C_(4)F_(7)N is considered to be the most potential alternative gas for SF_(6).However,harmful decomposition by-products generated by the discharge or overheating faults will pose threat to safe operation and service life of gas insulated equipment(GIE).Herein,we investigated the adsorption performance ofγ-Al_(2)O_(3)on C_(4)F_(7)N and its decomposition products to evaluate the possibility of using it as by-products adsorbent or exhaust treatment material.It is found thatγ-Al_(2)O_(3)demonstrates superior adsorption capacity for CF_(4),C_(2)F_(6),C_(3)F_(8),C_(3)F_(6),C_(2)F_(4),and keeps stable after the interaction.The first-principles calculation infers thatγ-Al_(2)O_(3)has stronger interaction with C_(4)F_(7)N,C_(3)F_(6)and C_(3)F_(8)than that of C_(2)F_(4),C_(2)F_(6)and CF_(4).There exists obvious charge transfer between C_(4)F_(7)N andγ-Al_(2)O_(3),which belongs to chemisorption.The interaction between F 2p orbital and C=Cπorbital determines the gas-solid adsorption performance.The desorption properties were also explored and the recovery time was in order of CF_(4)<C_(2)F_(6)<C_(2)F_(4)<C_(3)F_(8)<C_(4)F_(7)N<C_(3)F_(6).Overall,theγ-Al_(2)O_(3)is inappropriate to be used as the adsorbent for decomposition by-products of C_(4)F_(7)N gas mixture-based GIE,while it can be used as exhaust treatment material for C_(4)F_(7)N wasted gas.
基金the National Natural Science Foundation of China(Grant No.11871382)the Fundamental Research Funds for the Central Universities 2042020kf0031.
文摘Let u={u(t,x);(t,x)∈R_(+)×R}be the solution to a linear stochastic heat equation driven by a Gaussian noise,which is a Brownian motion in time and a fractional Brownian motion in space with Hurst parameter H∈(0,1).For any given x∈R(resp.,t∈R_(+)),we show a decomposition of the stochastic process t(→)u(t,x)(resp.,x(→)u(t,x))as the sum of a fractional Brownian motion with Hurst parameter H/2(resp.,H)and a stochastic process with C^(∞)-continuous trajectories.Some applications of those decompositions are discussed.
