N, O-carboxymethyl chitosan （NOCC） composite nanofiltration （NF） membranes were prepared by coating and cross-linking. The fermentation effluent from a wine factory was treated with the resulting NOCC/polysulfone ...N, O-carboxymethyl chitosan （NOCC） composite nanofiltration （NF） membranes were prepared by coating and cross-linking. The fermentation effluent from a wine factory was treated with the resulting NOCC/polysulfone （PSF） composite NF membranes. The permeate flux and the removal efficiencies of the resulting NF membranes for the color, chemical oxygen demand （CODcr）, total organic carbon （TOC）, and conductivity of the fermentation effluent were investigated in relation to the driving pressure, the feed flow, and the operation time. The permeate flux and the removal efficiencies were found to increase with the increase of the driving pressure or the feed flow. At 0.40 MPa and ambient temperature the removal efficiencies were 95.5%, 70.7%, 72.6%, and 31.6% for color, CODcr, TOC, and conductivity, respectively. The membrane was found to be stable over a 10-h ooeration for the fermentation effluent treatment.展开更多
Irritable bowel syndrome (IBS) is a functional gut disorder with high prevalence.Because of various factors involved in its pathophysiology and disappointing results from conventional IBS medications,the treatment of ...Irritable bowel syndrome (IBS) is a functional gut disorder with high prevalence.Because of various factors involved in its pathophysiology and disappointing results from conventional IBS medications,the treatment of IBS is challenging and use of complementary and alternative medicines especially herbal therapies is increasing.In this paper,electronic databases including PubMed,Scopus,and Cochrane library were searched to obtain any in vitro,in vivo or human studies evaluating single or compound herbal preparations in the management of IBS.One in vitro,3 in vivo and 23 human studies were included and systematically reviewed.The majority of studies are about essential oil of Menta piperita as a single preparation and STW 5 as a compound preparation.Some evaluated herbs such as Curcuma xanthorriza and Fumaria officinalis did not demonstrate any benefits in IBS.However,it seems there are many other herbal preparations such as those proposed in traditional medicine of different countries that could be studied and investigated for their efficacy in management of IBS.展开更多
In recent years, the researches on the theory and application of public articles and mechanism design at home and abroad has attracted more and more attentions. The paper uses the idea of mechanism design and simulati...In recent years, the researches on the theory and application of public articles and mechanism design at home and abroad has attracted more and more attentions. The paper uses the idea of mechanism design and simulation to analyze and solve environmental pollution improvement. By establishing a simple environmental pollution improvement model, the paper transforms pollution control into binary decision established by a sewage treatment plant and different decisions by the fisherman on the establishment of sewage treatment plants. The paper observes the results of applying different mechanisms and proposes the suggestions of implementin~ various pollution control methods.展开更多
In many developing countries, there are regions where the electrical grid is weak or nonexistent. However, in these areas, large amounts of distributed energy sources, such as hydro, are often available and could be s...In many developing countries, there are regions where the electrical grid is weak or nonexistent. However, in these areas, large amounts of distributed energy sources, such as hydro, are often available and could be suitably exploited. To this aim, the low head hydro power plants can play a significant role. In fact, recent technological advances in mini-hydro turbines and decreasing costs of static electricity conversion devices enable to realize suitable power plants for an efficient and profitable exploitation of these sites. One of the major challenges is the integration of the above-mentioned power plants into autonomous electrical systems, islanded and/or disconnectable from the main distribution network. In this paper, an innovative control strategy for a low head hydro power plant supplying users in small clusters of villages is proposed.展开更多
Most of the MHP （micro hydro power） plants use ELC （electronic load controller） for speed control. Various types of ELC have been developed so far. A dummy ballast load is connected across each phase of generator ...Most of the MHP （micro hydro power） plants use ELC （electronic load controller） for speed control. Various types of ELC have been developed so far. A dummy ballast load is connected across each phase of generator terminals and ELC controls the power consumed by the ballast load to result in constant speed operation. The ELC developed so far uses thyristor switches in each phase to control ballast load power. The ELC senses the system frequency and comparing it with reference frequency, it generates a common value of firing angle for all three thyristor pairs of each phase. The performance of such ELC is not perfect for unbalanced consumers load connected in each phase, which overloads the generator. This paper presents an advanced type of ELC which senses frequency as well as consumer＇s load current of each phase and fires the thyristor pairs with different value of firing angles for different phases. This solves the problem of overloading of the generator with unbalanced consumer＇s load. Simutink model is developed to perform transient analysis of the proposed scheme and the prototype of hardware is also fabricated. The simulation results and experimental results are presented.展开更多
基金the Special Funds for Major State Basic Research Program of China(2003CB615706)
文摘N, O-carboxymethyl chitosan （NOCC） composite nanofiltration （NF） membranes were prepared by coating and cross-linking. The fermentation effluent from a wine factory was treated with the resulting NOCC/polysulfone （PSF） composite NF membranes. The permeate flux and the removal efficiencies of the resulting NF membranes for the color, chemical oxygen demand （CODcr）, total organic carbon （TOC）, and conductivity of the fermentation effluent were investigated in relation to the driving pressure, the feed flow, and the operation time. The permeate flux and the removal efficiencies were found to increase with the increase of the driving pressure or the feed flow. At 0.40 MPa and ambient temperature the removal efficiencies were 95.5%, 70.7%, 72.6%, and 31.6% for color, CODcr, TOC, and conductivity, respectively. The membrane was found to be stable over a 10-h ooeration for the fermentation effluent treatment.
文摘Irritable bowel syndrome (IBS) is a functional gut disorder with high prevalence.Because of various factors involved in its pathophysiology and disappointing results from conventional IBS medications,the treatment of IBS is challenging and use of complementary and alternative medicines especially herbal therapies is increasing.In this paper,electronic databases including PubMed,Scopus,and Cochrane library were searched to obtain any in vitro,in vivo or human studies evaluating single or compound herbal preparations in the management of IBS.One in vitro,3 in vivo and 23 human studies were included and systematically reviewed.The majority of studies are about essential oil of Menta piperita as a single preparation and STW 5 as a compound preparation.Some evaluated herbs such as Curcuma xanthorriza and Fumaria officinalis did not demonstrate any benefits in IBS.However,it seems there are many other herbal preparations such as those proposed in traditional medicine of different countries that could be studied and investigated for their efficacy in management of IBS.
文摘In recent years, the researches on the theory and application of public articles and mechanism design at home and abroad has attracted more and more attentions. The paper uses the idea of mechanism design and simulation to analyze and solve environmental pollution improvement. By establishing a simple environmental pollution improvement model, the paper transforms pollution control into binary decision established by a sewage treatment plant and different decisions by the fisherman on the establishment of sewage treatment plants. The paper observes the results of applying different mechanisms and proposes the suggestions of implementin~ various pollution control methods.
文摘In many developing countries, there are regions where the electrical grid is weak or nonexistent. However, in these areas, large amounts of distributed energy sources, such as hydro, are often available and could be suitably exploited. To this aim, the low head hydro power plants can play a significant role. In fact, recent technological advances in mini-hydro turbines and decreasing costs of static electricity conversion devices enable to realize suitable power plants for an efficient and profitable exploitation of these sites. One of the major challenges is the integration of the above-mentioned power plants into autonomous electrical systems, islanded and/or disconnectable from the main distribution network. In this paper, an innovative control strategy for a low head hydro power plant supplying users in small clusters of villages is proposed.
文摘Most of the MHP （micro hydro power） plants use ELC （electronic load controller） for speed control. Various types of ELC have been developed so far. A dummy ballast load is connected across each phase of generator terminals and ELC controls the power consumed by the ballast load to result in constant speed operation. The ELC developed so far uses thyristor switches in each phase to control ballast load power. The ELC senses the system frequency and comparing it with reference frequency, it generates a common value of firing angle for all three thyristor pairs of each phase. The performance of such ELC is not perfect for unbalanced consumers load connected in each phase, which overloads the generator. This paper presents an advanced type of ELC which senses frequency as well as consumer＇s load current of each phase and fires the thyristor pairs with different value of firing angles for different phases. This solves the problem of overloading of the generator with unbalanced consumer＇s load. Simutink model is developed to perform transient analysis of the proposed scheme and the prototype of hardware is also fabricated. The simulation results and experimental results are presented.
