This study investigates how artificial intelligence(AI)algorithms enable mainstream media to achieve precise emotional matching and improve communication efficiency through reconstructed communication logic.As digital...This study investigates how artificial intelligence(AI)algorithms enable mainstream media to achieve precise emotional matching and improve communication efficiency through reconstructed communication logic.As digital intelligence technology rapidly evolves,mainstream media organizations are increasingly leveraging AI-driven empathy algorithms to enhance audience engagement and optimize content delivery.This research employs a mixed-methods approach,combining quantitative analysis of algorithmic performance metrics with qualitative examination of media communication patterns.Through systematic review of 150 academic papers and analysis of data from 12 major media platforms,this study reveals that algorithmic empathy systems can improve emotional resonance by 34.7%and increase audience engagement by 28.3%compared to traditional communication methods.The findings demonstrate that AI algorithms reconstruct media communication logic through three primary pathways:emotional pattern recognition,personalized content curation,and real-time sentiment adaptation.However,the study also identifies significant challenges including algorithmic bias,emotional authenticity concerns,and ethical implications of automated empathy.The research contributes to understanding how mainstream media can leverage AI technology to build high-quality empathetic communication while maintaining journalistic integrity and social responsibility.展开更多
The United Nations(UN)has always been a proactive promoter of mainstreaming human rights,while the Charter of the United Nations is the cornerstone and starting point for this endeavor.The mainstreaming of human right...The United Nations(UN)has always been a proactive promoter of mainstreaming human rights,while the Charter of the United Nations is the cornerstone and starting point for this endeavor.The mainstreaming of human rights is a principle and direction of UN reform,as the UN has promoted it through human rights institutions reform and institutional building.Reviewing the UN’s many years of practice in promoting the mainstreaming of human rights,it is evident that its various departments and agencies have formed a united front already,which is specifically manifested in the following ways:The UN Secretary-General puts forward reform plans to promote the mainstreaming of human rights and issues relevant initiatives and calls to action;the mechanism of mainstreaming of human rights provides institutional and financial support;the UN Development Group(later renamed the UN Sustainable Development Group)is the main platform for the UN to promote the mainstreaming of human rights;the Office of the High Commissioner for Human Rights and the Human Rights Council are the main implementing bodies for the UN to promote the mainstreaming of human rights;and other UN agencies actively respond to and implement the requirements of the mainstreaming of human rights in their respective areas of work.展开更多
Anammox is widely considered as the most cost-effective and sustainable process for nitrogen removal.However,how to achieve the enrichment of anammox biomass remains a challenge for its large-scale application,especia...Anammox is widely considered as the most cost-effective and sustainable process for nitrogen removal.However,how to achieve the enrichment of anammox biomass remains a challenge for its large-scale application,especially in mainstream wastewater treatment.In this study,the feasibility of enrichment of anammox biomass was explored through the realization of partial denitrification and the addition of bio-carriers.By using ordinary activated sludge,a sequencing batch reactor(SBR)followed by an up-fow anaerobic sludge bed(UASB)was operated at 25±2℃ for 214 days.The long-term operation was divided into five phases,in which SBR and UASB were started-up in Phases I and II,respectively.By eliminating oxygen and adjusting the infow ratios in Phases III-V,advanced nitrogen removal was achieved with the effuent total nitrogen being 4.7 mg/L and the nitrogen removal efficiency being 90.5%in Phase V.Both in-situ and ex-situ activity tests demonstrated the occurrence of partial denitrification and anammox.Moreover,16S rRNA high-throughput sequencing analysis revealed that Candidatus Brocadia was enriched from below the detection limit to in biofilms(0.4%in SBR,2.2%in UASB)and the foc sludge(0.2%in SBR,1.3%in UASB),while Thauera was mainly detected in the foc sludge(8.1%in SBR,8.8%in UASB),which might play a key role in partial denitrification.Overall,this study provides a novel strategy to enrich anammox biomass driven by rapid achievement of partial denitrification through the addition of bio-carriers,which will improve large-scale application of anammox processes in mainstream wastewater treatment.展开更多
According to the response relationship between landscape and water resource,the selection principle of important landscapes was determined from the perspectives of nature and history in this study,and determination me...According to the response relationship between landscape and water resource,the selection principle of important landscapes was determined from the perspectives of nature and history in this study,and determination methods or steps of important landscapes along the mainstream of Yellow River were also established to select important landscapes that should be protected.展开更多
The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the ...The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the mountainous watershed of the Heihe Mainstream River as a study area to simulate the hydrological processes of mountainous watersheds in inland river basins by using the soil and water assessment tool(SWAT)model.SWAT simulation results show that both the Nash–Sutcliffe efficiency and the determination coefficient values of the calibration period(January 1995 to December 2002)and validation period(January 2002 to December 2009)are higher than 0.90,and the percent bias is controlled within±5%,indicating that the simulation results are satisfactory.According to the SWAT performance,we discussed the yearly and monthly variation trends of the mountainous runoff and the runoff components.The results show that from 1996 to 2009,an indistinctive rising trend was observed for the yearly mountainous runoff,which is mainly recharged by lateral flow,and followed by shallow groundwater runoff and surface runoff.The monthly variation demonstrates that the mountainous runoff decreases slightly from May to July,contrary to other months.The mountainous runoff is mainly recharged by shallow groundwater runoff in January,February,and from October to December,by surface runoff in March and April,and by lateral flow from May to September.展开更多
Residual ammonium is a critical parameter affecting the stability of mainstream partial nitritation/anammox(PN/A), but the underlying mechanism remains unclear. In this study,mainstream PN/A was established and operat...Residual ammonium is a critical parameter affecting the stability of mainstream partial nitritation/anammox(PN/A), but the underlying mechanism remains unclear. In this study,mainstream PN/A was established and operated with progressively decreasing residual ammonium. PN/A deteriorated as the residual ammonium decreased to below 5 mg/L, and this was paralleled by a significant loss in anammox activity in situ and an increasing nitrite oxidation rate. Further analysis revealed that the low-ammonium condition directly decreased anammox activity in situ via two distinct mechanisms. First, anammox bacteria were located in the inner layer of the granular sludge, and thus were disadvantageous when competing for ammonium with ammonium-oxidizing bacteria(AOB) in the outer layer. Second, the complete ammonia oxidizer(comammox) was enriched at low residual ammonium concentrations because of its high ammonium affinity. Both AOB and comammox presented kinetic advantages over anammox bacteria. At high residual ammonium concentrations,nitrite-oxidizing bacteria(NOB) were effectively suppressed, even when their maximum activity was high due to competition for nitrite with anammox bacteria. At low residual ammonium concentrations, the decrease in anammox activity in situ led to an increase in nitrite availability for nitrite oxidation, facilitating the activation of NOB despite the dissolved oxygen limitation(0.15–0.35 mg/L) for NOB persisting throughout the operation. Therefore, the deterioration of mainstream PN/A at low residual ammonium was primarily triggered by a decline in anammox activity in situ. This study provides novel insights into the optimized design of mainstream PN/As in engineering applications.展开更多
This study investigated the removal of heavy metal ions from cigarette mainstream smoke using chitosan. Chitosan of various deacetylation degrees and molecular weights were manually added to cigarette filters in diffe...This study investigated the removal of heavy metal ions from cigarette mainstream smoke using chitosan. Chitosan of various deacetylation degrees and molecular weights were manually added to cigarette filters in different dosages. The mainstream smoke particulate matter was collected by a Cambridge filter pad, digested by a microwave digestor, and then analyzed for contents of heavy metal ions, including As(Ill/V), Pb(II), Cd(II), Cr(III/VI) and Ni(II), by graphite furnace atomic absorption spectrometry (GFAAS). The results showed that chitosan had a removal effect on Pb(II), Cd(II), Cr(III/VI) and Ni(II). Of these, the percent re- moval of Ni(II) was elevated with an increasing dosage of chitosan. Chitosan of a high deace tylation degree exhibited good binding performance toward Cd(II), Cr(III/VI) and Ni(II), though with poor efficiency for Pb(II). Except As(III/V), all the tested metal ions showed similar tendencies in the growing contents with an increasing chitosan molecular weight. Nonetheless, the percent removal of Cr(III/VI) peaked with a chitosan molecular weight of 200 kDa, followed by a dramatic decrease with an increasing chitosan mo- lecular weight. Generally, chitosan had different removal effects on four out of five tested metal ions, and the percent removal of Cd(II), Pb(II), Cr(III/VI) and Ni(II) was approximately 55%, 45%, 50%, and 16%, respectively. In a word, chitosan used in cigarette filter can remove toxic heavy metal ions in the mainstream smoke, improve cigarette safety, and reduce the harm to smokers.展开更多
Cigarette smoking is a particle-related exposure. Studying the characteristics of the particle size distribution of cigarette smoke can aid in providing knowledge of smoke aerosol attributes. We used an electrical low...Cigarette smoking is a particle-related exposure. Studying the characteristics of the particle size distribution of cigarette smoke can aid in providing knowledge of smoke aerosol attributes. We used an electrical low pressure impactor (ELPI) to measure the particle size distribution of mainstream cigarette smoke generated by a smoking machine and provided a continuum of particle sizes of cigarette smoke from a whole cigarette. The results showed that the aerodynamic diameters (D, geometric mean of a channel) of particles ranged from 0.021 to 1.956 ~m, and the number concentrations were on the order of 105-109 cm-3 for different sizes of particles. The particle number of the size category below 0.1 p,m approximated that of the category 0.1-2.0 Ixm, and the particles in the size category of 0.1-2.0 μm contributed extremely heavily to total particulate mass. In addition, the results with small samples indicated that the tar yields normalized per milligram of nicotine showed an approximately linear increase with increasing concentration of total particles.展开更多
An improved method was developed for the determination of the four major tobacco-specific nitrosamines(TSNAs) in mainstream cigarette smoke. The new method offers decreased sample preparation and analysis time as co...An improved method was developed for the determination of the four major tobacco-specific nitrosamines(TSNAs) in mainstream cigarette smoke. The new method offers decreased sample preparation and analysis time as compared to traditional methods. This method uses isotope dilution liquid chromatography coupled with a tandem mass spectrometer with electrospray ionization and is significantly more sensitive than traditional methods. It also shows no evidence of artifactual formation of TSNAs. Sample concentrations were determined for four TSNAs in mainstream smoke using two isotopically labeled TSNAs analogues as internal standards. Mainstream smoke was collected on an industry standard 44-ram Cambridge filter pad, extracted with 0.1 mol/L ammonium acetate, purified by solid-phase extraction, and analyzed without further sample cleanup. The analytical column is a 3.9 mm×150 mm Waters Symmertry Shield RP18 column and volume fraction of the mobile phase is 50% methanol, 50% water containing 0.1% acetic acid. The results show that the linear range is 0.5-100.0 mg/L except for N-nitrosoanabasine (NAB) from 0.25 to 50.0 mg/L. The limits of detection are 0.1 mg/L for N-nitrosonornicotine (NNN), 0.08 mg/L for 4-(methylnitrosamino)-1- (3-py-ridyl)-1-butanone (NNK), 0.05 mg/L for N-nitrosoanatabine (NAT) and 0.06 mg/L for NAB. The recoveries of the four TSNAs are from 90.2% to 105.7%.展开更多
To understand the retention mechanism of phenol in mainstream cigarette smoke by cellulose acetate(CA)filters,the phenol filtration efficiency,the phenol distribution in the gas phase and particulate phase during filt...To understand the retention mechanism of phenol in mainstream cigarette smoke by cellulose acetate(CA)filters,the phenol filtration efficiency,the phenol distribution in the gas phase and particulate phase during filtration and the retention characteristics of the filter for both the gas phase and particulate phenol species were investigated.The distribution of particulate bound phenol as a function of the particle size was examined.The ratio of phenol transferring from the particulate phase to the gas phase during smoke flowing through the CA filter were studied.Retention mechanisms for phenol in the gas phase as well as particulate phase phenol in the filter and the phase transition of phenol were proposed.Phenol filtration efficiency of the cigarette filter was calculated based on the proposed retention mechanisms and compared with available experimental data.The results showed that:1)Comparing with nicotine and the other particulate bound smoke constituents,CA filter exhibited a certain retention selectivity for phenol.2)Although phenol was mainly bound to the particulate phase of the cigarette mainstream smoke,about 35% of gas phase phenol was found at the tobacco end of the filter,whilst this dropped to approximately 0 at the mouth end of the filter,mostly by selective chemical adsorption.3)The weighted average smoke particle size and particulate phenol was 0.44 and 0.38 pm,respectively.The filtration efficiency of the filter to particulate phenol was near 40%.4)About 19% of particulate bound phenol transferred to gas phase when smoke passing the filter,and was selectively adsorbed.5)The overall filtration efficiency of the CA filter for phenol in mainstream cigarette smoke was 68.7%,with-7.7% variation compared with experimental data.The results demonstrated the phase transition of phenol during the filtration process and the selective retention with varying particle sizes.Our results showed that the application of CA filter in product designs reduces harmful constituents such as phenolic compounds in mainstream cigarette smoke.展开更多
A series of Ag,Cu and Co-doped manganese oxide octahedral molecular sieves(OMS-2) were synthesized and evaluated to remove nitrogen oxides(NOx) from cigarette mainstream smoke.The three kinds of catalysts were added t...A series of Ag,Cu and Co-doped manganese oxide octahedral molecular sieves(OMS-2) were synthesized and evaluated to remove nitrogen oxides(NOx) from cigarette mainstream smoke.The three kinds of catalysts were added to cigarettes for studying the capabilities of reducing NOx from cigarette mainstream smoke.The catalysis and reduction of NO in laboratory were studied.A mechanism for NOx catalytic reduction from burning cigarettes with the catalysts adding to cigarettes was described.The catalysts show excellent catalytic activity for NOx removal,especially the Ag-doped OMS-2 catalyst.0.5%(mass fraction) Ag-doped OMS-2 catalyst has the best ability to remove NOx from cigarette mainstream smoke.The use of Ag-doped OMS-2 as catalyst for removing carcinogenic compounds from cigarette smoke will be an effective strategy to protect the environment and public health.展开更多
Mainstream line is significant for the Yellow River situation forecasting and flood control.An effective statistical feature extraction method is proposed in this paper.In this method, a between-class scattering matri...Mainstream line is significant for the Yellow River situation forecasting and flood control.An effective statistical feature extraction method is proposed in this paper.In this method, a between-class scattering matrix based projection algorithm is performed to maximize between-class differences, obtaining effective component for classification;then high-order statistics are utilized as the features to describe the mainstream line in the principal component obtained.Experiments are performed to verify the applicability of the algorithm.The results both on synthesized and real scenes indicate that this approach could extract the mainstream line of the Yellow River automatically, and has a high precision in mainstream line detection.展开更多
[Objective] The study aims at evaluating the water environmental quality of the Liaohe River mainstream. [ Method] The water quality of two monitored sections in the mainstream of the Liaohe River from 2004 to 2010 wa...[Objective] The study aims at evaluating the water environmental quality of the Liaohe River mainstream. [ Method] The water quality of two monitored sections in the mainstream of the Liaohe River from 2004 to 2010 was assessed by the fuzzy comprehensive appraisal combined with weighted average, and some practicable measures were put forward according to the assessment results. [ Result] From 2004 to 2010, the water quality of the Liaohe River mainstream varied from Grade II to III at Zhuershan section, and changed from Grade II to IV at Xing'an section, becom- ing better on the whole. In addition, the major factor influencing the water quality is the small content of dissolved oxygen (DO) in the water body. Meanwhile, the pollution of the water body mainly results from the discharge of organic matter consuming oxygen largely, and ammonia nitrogen should be paid more attention to. [ Conclusion] The research could provide scientific references for the protection of water environment and its pollu- tion control in the mainstream of the Liaohe River.展开更多
With development of foreign language education in China, more and more people pay attention to the research of the mainstream EFL teaching styles, which combines the seemingly contradictory points of both traditional ...With development of foreign language education in China, more and more people pay attention to the research of the mainstream EFL teaching styles, which combines the seemingly contradictory points of both traditional and current linguistic theories and use them well in foreign language teaching. With special features, the mainstream EFL teaching style has its advantage and weakness and it needs much improvement in teaching process.展开更多
In this paper,the author starts with a discussion of what mainstream linguistics is,in aim of clearly defining mainstream linguistics.Then the author further makes a distinction and comparison between mainstream lingu...In this paper,the author starts with a discussion of what mainstream linguistics is,in aim of clearly defining mainstream linguistics.Then the author further makes a distinction and comparison between mainstream linguistics and non-mainstream linguistics.In the third part of the paper,the author probes into and reflects on the main criticisms of mainstream linguistics.展开更多
In Tanzania 80% of the population live in informal settlements. Most of these settlements are built in areas that are susceptible to extreme weather conditions such as flooding. Such conditions have significantly cont...In Tanzania 80% of the population live in informal settlements. Most of these settlements are built in areas that are susceptible to extreme weather conditions such as flooding. Such conditions have significantly contributed to the destruction of housing stock and other valuable properties. There is considerable awareness amongst people living in the informal settlements, government representatives and other key stakeholders about the various flood risks affecting informal settlements. Based on this understanding, several attempts to minimize flood risks have been initiated in Dar es Salaam, Tanzania, yet these initiatives have largely failed to deliver the desired impacts. This article aims to investigate core reasons for this through a case study of Keko Machungwa Informal settlement in Dar es Salaam City. The study explores the extent to which mainstreaming of disaster risk reduction (DRR) in housing development in informal settlements has been considered and implemented, and recommends measures for improvement. Key methods employed for the research included physical observation, household interviews, mapping, photographing, and in-depth interviews. Overall, the study found that mainstreaming of DRR in housing development was hardly practiced at the household level, as houses were predominantly being built without resistant building materials and supervision of relevant professionals. In order to mainstream DRR in housing development in informal settlements, it is recommended that mainstreaming DRR be embedded in laws and policies, highly vulnerable parts of the settlement be declared protected wetland and that the government direct its efforts towards regulating, controlling and monitoring the housing development sector. That letter can be achieved by emphasizing the use of flood resistant building materials and establishing resilient infrastructures for flood mitigation in every flood prone informal settlement.展开更多
[ Objective] To explore the effect of expansion temperature on the release of seven kinds of Hoffmann components (CO, NNK, NH3, HCN,, BaP, crotonaldehyde and phenol) from the mainstream smoke of cigarette. [ Method]...[ Objective] To explore the effect of expansion temperature on the release of seven kinds of Hoffmann components (CO, NNK, NH3, HCN,, BaP, crotonaldehyde and phenol) from the mainstream smoke of cigarette. [ Method] The release amount of seven kinds of Hoffmann com-ponents from the mainstream smoke of cigarettes which were prepared from the cut tobacco treated under different expansion temperatures was de-termined. [ Result] Under the same expansion model, the temperature change produced certain impact on the release amount of NH~, phenol and BAP, while had no significant influence on that of CO, NNK, HCN and crotonaldehyde; under CO2 expansion model, the release amount of seven Hoffmann components was small; the reduction of expansion temperature was good for lowering the harmful index of cigarette to a certain extent. [ Conclusion] The study provides basis for optimizing the technical parameters of producinq less harmful cigarette.展开更多
The adoption and use of social media has played a major role in the changes in journalists’ work. The use of these new means has become indispensable to the daily tasks and work of journalists in most news organizati...The adoption and use of social media has played a major role in the changes in journalists’ work. The use of these new means has become indispensable to the daily tasks and work of journalists in most news organizations. It is no longer possible to bypass these means when it comes to searching for information and news, or in production, publishing, distribution and marketing, or even in interaction with the public. The characteristics of ease, speed, immediacy, interactivity, and being free of charge that characterize them, have made them a useful technological tool, which is influential and necessary not only for the future of the journalist’s career but also for the future of the news organization itself. With the growing number of users of social media around the world, journalists and news organizations have found additional access, more important than previous channels, to access additional sources that help them market and interact with their work in a new dynamic environment completely different from previous communication models, and put audience activity at the forefront. In this study, which is part of the Technology Acceptance Model (TAM), the author tries to understand and analyze the factors of adoption and use of social media as a new technological tool by Bahraini journalists and to identify their new role in the changes in journalism. In addition, the study attempts to examine the implications in relation to the future of the press profession and the economic model of the news organization. The results showed a clear adoption and an increased use of social media by journalists, who consider it a key element in the development of journalism, and an inevitable strategic choice for the future of the news organization. They also expressed their full awareness of the problems surrounding the issue of precision and credibility of news accessed through social media.展开更多
The gender mainstreaming policy has developed with the change of culture in Taiwan from 2001 to 2012. Based on literature review, this paper discusses the change of culture and the development of gender mainstreaming ...The gender mainstreaming policy has developed with the change of culture in Taiwan from 2001 to 2012. Based on literature review, this paper discusses the change of culture and the development of gender mainstreaming policy with "Gender at Work Framework" to explain the difference between change at the formal, organizational level and change at the informal and personal level for addressing the root causes of gender equality. This research finds that to achieve gender mainstreaming policy goal, the government has to foster robust, and sound cultural basis for the society.展开更多
文摘This study investigates how artificial intelligence(AI)algorithms enable mainstream media to achieve precise emotional matching and improve communication efficiency through reconstructed communication logic.As digital intelligence technology rapidly evolves,mainstream media organizations are increasingly leveraging AI-driven empathy algorithms to enhance audience engagement and optimize content delivery.This research employs a mixed-methods approach,combining quantitative analysis of algorithmic performance metrics with qualitative examination of media communication patterns.Through systematic review of 150 academic papers and analysis of data from 12 major media platforms,this study reveals that algorithmic empathy systems can improve emotional resonance by 34.7%and increase audience engagement by 28.3%compared to traditional communication methods.The findings demonstrate that AI algorithms reconstruct media communication logic through three primary pathways:emotional pattern recognition,personalized content curation,and real-time sentiment adaptation.However,the study also identifies significant challenges including algorithmic bias,emotional authenticity concerns,and ethical implications of automated empathy.The research contributes to understanding how mainstream media can leverage AI technology to build high-quality empathetic communication while maintaining journalistic integrity and social responsibility.
文摘The United Nations(UN)has always been a proactive promoter of mainstreaming human rights,while the Charter of the United Nations is the cornerstone and starting point for this endeavor.The mainstreaming of human rights is a principle and direction of UN reform,as the UN has promoted it through human rights institutions reform and institutional building.Reviewing the UN’s many years of practice in promoting the mainstreaming of human rights,it is evident that its various departments and agencies have formed a united front already,which is specifically manifested in the following ways:The UN Secretary-General puts forward reform plans to promote the mainstreaming of human rights and issues relevant initiatives and calls to action;the mechanism of mainstreaming of human rights provides institutional and financial support;the UN Development Group(later renamed the UN Sustainable Development Group)is the main platform for the UN to promote the mainstreaming of human rights;the Office of the High Commissioner for Human Rights and the Human Rights Council are the main implementing bodies for the UN to promote the mainstreaming of human rights;and other UN agencies actively respond to and implement the requirements of the mainstreaming of human rights in their respective areas of work.
基金supported by the National Natural Science Foundation of China (No.22176007),the Beijing Natural Science Foundation (No.8212022)the fund of innovation and entrepreneurship leading team project in Guangzhou (No.CYLJTD-201607)the National Key Research and Development Program of China (No.2021YFC3200605)。
文摘Anammox is widely considered as the most cost-effective and sustainable process for nitrogen removal.However,how to achieve the enrichment of anammox biomass remains a challenge for its large-scale application,especially in mainstream wastewater treatment.In this study,the feasibility of enrichment of anammox biomass was explored through the realization of partial denitrification and the addition of bio-carriers.By using ordinary activated sludge,a sequencing batch reactor(SBR)followed by an up-fow anaerobic sludge bed(UASB)was operated at 25±2℃ for 214 days.The long-term operation was divided into five phases,in which SBR and UASB were started-up in Phases I and II,respectively.By eliminating oxygen and adjusting the infow ratios in Phases III-V,advanced nitrogen removal was achieved with the effuent total nitrogen being 4.7 mg/L and the nitrogen removal efficiency being 90.5%in Phase V.Both in-situ and ex-situ activity tests demonstrated the occurrence of partial denitrification and anammox.Moreover,16S rRNA high-throughput sequencing analysis revealed that Candidatus Brocadia was enriched from below the detection limit to in biofilms(0.4%in SBR,2.2%in UASB)and the foc sludge(0.2%in SBR,1.3%in UASB),while Thauera was mainly detected in the foc sludge(8.1%in SBR,8.8%in UASB),which might play a key role in partial denitrification.Overall,this study provides a novel strategy to enrich anammox biomass driven by rapid achievement of partial denitrification through the addition of bio-carriers,which will improve large-scale application of anammox processes in mainstream wastewater treatment.
基金Supported by Modern Water Science Innovation Project of Ministry of Water Resources(XD2004-03-05)Key Project for National Science and Technology Supporting Plan during the Eleventh Five-Year Plan(2006BAB06B08-04)~~
文摘According to the response relationship between landscape and water resource,the selection principle of important landscapes was determined from the perspectives of nature and history in this study,and determination methods or steps of important landscapes along the mainstream of Yellow River were also established to select important landscapes that should be protected.
基金supported by the National Natural Science Foundation of China(41240002,91125025,91225302,Y211121001)the National Science and Technology Support Projects(2011BAC07B05)
文摘The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the mountainous watershed of the Heihe Mainstream River as a study area to simulate the hydrological processes of mountainous watersheds in inland river basins by using the soil and water assessment tool(SWAT)model.SWAT simulation results show that both the Nash–Sutcliffe efficiency and the determination coefficient values of the calibration period(January 1995 to December 2002)and validation period(January 2002 to December 2009)are higher than 0.90,and the percent bias is controlled within±5%,indicating that the simulation results are satisfactory.According to the SWAT performance,we discussed the yearly and monthly variation trends of the mountainous runoff and the runoff components.The results show that from 1996 to 2009,an indistinctive rising trend was observed for the yearly mountainous runoff,which is mainly recharged by lateral flow,and followed by shallow groundwater runoff and surface runoff.The monthly variation demonstrates that the mountainous runoff decreases slightly from May to July,contrary to other months.The mountainous runoff is mainly recharged by shallow groundwater runoff in January,February,and from October to December,by surface runoff in March and April,and by lateral flow from May to September.
基金financially supported by the Natural Science Foundation of Shandong Province, China (No. ZR2019BEE070)a Project of Shandong Province Higher Educational Science and Technology Program (No. J18KA207)。
文摘Residual ammonium is a critical parameter affecting the stability of mainstream partial nitritation/anammox(PN/A), but the underlying mechanism remains unclear. In this study,mainstream PN/A was established and operated with progressively decreasing residual ammonium. PN/A deteriorated as the residual ammonium decreased to below 5 mg/L, and this was paralleled by a significant loss in anammox activity in situ and an increasing nitrite oxidation rate. Further analysis revealed that the low-ammonium condition directly decreased anammox activity in situ via two distinct mechanisms. First, anammox bacteria were located in the inner layer of the granular sludge, and thus were disadvantageous when competing for ammonium with ammonium-oxidizing bacteria(AOB) in the outer layer. Second, the complete ammonia oxidizer(comammox) was enriched at low residual ammonium concentrations because of its high ammonium affinity. Both AOB and comammox presented kinetic advantages over anammox bacteria. At high residual ammonium concentrations,nitrite-oxidizing bacteria(NOB) were effectively suppressed, even when their maximum activity was high due to competition for nitrite with anammox bacteria. At low residual ammonium concentrations, the decrease in anammox activity in situ led to an increase in nitrite availability for nitrite oxidation, facilitating the activation of NOB despite the dissolved oxygen limitation(0.15–0.35 mg/L) for NOB persisting throughout the operation. Therefore, the deterioration of mainstream PN/A at low residual ammonium was primarily triggered by a decline in anammox activity in situ. This study provides novel insights into the optimized design of mainstream PN/As in engineering applications.
基金supported by the Natural Science Foundation of China(No.30972289)Ocean Public Welfare Scientific Research Special Appropriation Project(No.201005020)
文摘This study investigated the removal of heavy metal ions from cigarette mainstream smoke using chitosan. Chitosan of various deacetylation degrees and molecular weights were manually added to cigarette filters in different dosages. The mainstream smoke particulate matter was collected by a Cambridge filter pad, digested by a microwave digestor, and then analyzed for contents of heavy metal ions, including As(Ill/V), Pb(II), Cd(II), Cr(III/VI) and Ni(II), by graphite furnace atomic absorption spectrometry (GFAAS). The results showed that chitosan had a removal effect on Pb(II), Cd(II), Cr(III/VI) and Ni(II). Of these, the percent re- moval of Ni(II) was elevated with an increasing dosage of chitosan. Chitosan of a high deace tylation degree exhibited good binding performance toward Cd(II), Cr(III/VI) and Ni(II), though with poor efficiency for Pb(II). Except As(III/V), all the tested metal ions showed similar tendencies in the growing contents with an increasing chitosan molecular weight. Nonetheless, the percent removal of Cr(III/VI) peaked with a chitosan molecular weight of 200 kDa, followed by a dramatic decrease with an increasing chitosan mo- lecular weight. Generally, chitosan had different removal effects on four out of five tested metal ions, and the percent removal of Cd(II), Pb(II), Cr(III/VI) and Ni(II) was approximately 55%, 45%, 50%, and 16%, respectively. In a word, chitosan used in cigarette filter can remove toxic heavy metal ions in the mainstream smoke, improve cigarette safety, and reduce the harm to smokers.
基金supported by the National Natural Science Foundation of China(No.21007094)to Xiang Li
文摘Cigarette smoking is a particle-related exposure. Studying the characteristics of the particle size distribution of cigarette smoke can aid in providing knowledge of smoke aerosol attributes. We used an electrical low pressure impactor (ELPI) to measure the particle size distribution of mainstream cigarette smoke generated by a smoking machine and provided a continuum of particle sizes of cigarette smoke from a whole cigarette. The results showed that the aerodynamic diameters (D, geometric mean of a channel) of particles ranged from 0.021 to 1.956 ~m, and the number concentrations were on the order of 105-109 cm-3 for different sizes of particles. The particle number of the size category below 0.1 p,m approximated that of the category 0.1-2.0 Ixm, and the particles in the size category of 0.1-2.0 μm contributed extremely heavily to total particulate mass. In addition, the results with small samples indicated that the tar yields normalized per milligram of nicotine showed an approximately linear increase with increasing concentration of total particles.
基金Project(2005JC02) supported by China Tobacco Hunan Industrial Corporation Limited
文摘An improved method was developed for the determination of the four major tobacco-specific nitrosamines(TSNAs) in mainstream cigarette smoke. The new method offers decreased sample preparation and analysis time as compared to traditional methods. This method uses isotope dilution liquid chromatography coupled with a tandem mass spectrometer with electrospray ionization and is significantly more sensitive than traditional methods. It also shows no evidence of artifactual formation of TSNAs. Sample concentrations were determined for four TSNAs in mainstream smoke using two isotopically labeled TSNAs analogues as internal standards. Mainstream smoke was collected on an industry standard 44-ram Cambridge filter pad, extracted with 0.1 mol/L ammonium acetate, purified by solid-phase extraction, and analyzed without further sample cleanup. The analytical column is a 3.9 mm×150 mm Waters Symmertry Shield RP18 column and volume fraction of the mobile phase is 50% methanol, 50% water containing 0.1% acetic acid. The results show that the linear range is 0.5-100.0 mg/L except for N-nitrosoanabasine (NAB) from 0.25 to 50.0 mg/L. The limits of detection are 0.1 mg/L for N-nitrosonornicotine (NNN), 0.08 mg/L for 4-(methylnitrosamino)-1- (3-py-ridyl)-1-butanone (NNK), 0.05 mg/L for N-nitrosoanatabine (NAT) and 0.06 mg/L for NAB. The recoveries of the four TSNAs are from 90.2% to 105.7%.
文摘To understand the retention mechanism of phenol in mainstream cigarette smoke by cellulose acetate(CA)filters,the phenol filtration efficiency,the phenol distribution in the gas phase and particulate phase during filtration and the retention characteristics of the filter for both the gas phase and particulate phenol species were investigated.The distribution of particulate bound phenol as a function of the particle size was examined.The ratio of phenol transferring from the particulate phase to the gas phase during smoke flowing through the CA filter were studied.Retention mechanisms for phenol in the gas phase as well as particulate phase phenol in the filter and the phase transition of phenol were proposed.Phenol filtration efficiency of the cigarette filter was calculated based on the proposed retention mechanisms and compared with available experimental data.The results showed that:1)Comparing with nicotine and the other particulate bound smoke constituents,CA filter exhibited a certain retention selectivity for phenol.2)Although phenol was mainly bound to the particulate phase of the cigarette mainstream smoke,about 35% of gas phase phenol was found at the tobacco end of the filter,whilst this dropped to approximately 0 at the mouth end of the filter,mostly by selective chemical adsorption.3)The weighted average smoke particle size and particulate phenol was 0.44 and 0.38 pm,respectively.The filtration efficiency of the filter to particulate phenol was near 40%.4)About 19% of particulate bound phenol transferred to gas phase when smoke passing the filter,and was selectively adsorbed.5)The overall filtration efficiency of the CA filter for phenol in mainstream cigarette smoke was 68.7%,with-7.7% variation compared with experimental data.The results demonstrated the phase transition of phenol during the filtration process and the selective retention with varying particle sizes.Our results showed that the application of CA filter in product designs reduces harmful constituents such as phenolic compounds in mainstream cigarette smoke.
文摘A series of Ag,Cu and Co-doped manganese oxide octahedral molecular sieves(OMS-2) were synthesized and evaluated to remove nitrogen oxides(NOx) from cigarette mainstream smoke.The three kinds of catalysts were added to cigarettes for studying the capabilities of reducing NOx from cigarette mainstream smoke.The catalysis and reduction of NO in laboratory were studied.A mechanism for NOx catalytic reduction from burning cigarettes with the catalysts adding to cigarettes was described.The catalysts show excellent catalytic activity for NOx removal,especially the Ag-doped OMS-2 catalyst.0.5%(mass fraction) Ag-doped OMS-2 catalyst has the best ability to remove NOx from cigarette mainstream smoke.The use of Ag-doped OMS-2 as catalyst for removing carcinogenic compounds from cigarette smoke will be an effective strategy to protect the environment and public health.
基金supported by the Flood Control Foundation of Yellow River Conservancy Commissionthe 2007 Key Supporting Project on Undergraduate Graduation Thesis of North-western Polytechnical University.
文摘Mainstream line is significant for the Yellow River situation forecasting and flood control.An effective statistical feature extraction method is proposed in this paper.In this method, a between-class scattering matrix based projection algorithm is performed to maximize between-class differences, obtaining effective component for classification;then high-order statistics are utilized as the features to describe the mainstream line in the principal component obtained.Experiments are performed to verify the applicability of the algorithm.The results both on synthesized and real scenes indicate that this approach could extract the mainstream line of the Yellow River automatically, and has a high precision in mainstream line detection.
基金Supported by National Natural Science Foundation of China (11075135)Key Project Supporting Historical and Geographical Subject of Shaanxi Province (10722,60103)Key Subject Project of Xianyang Normal University
文摘[Objective] The study aims at evaluating the water environmental quality of the Liaohe River mainstream. [ Method] The water quality of two monitored sections in the mainstream of the Liaohe River from 2004 to 2010 was assessed by the fuzzy comprehensive appraisal combined with weighted average, and some practicable measures were put forward according to the assessment results. [ Result] From 2004 to 2010, the water quality of the Liaohe River mainstream varied from Grade II to III at Zhuershan section, and changed from Grade II to IV at Xing'an section, becom- ing better on the whole. In addition, the major factor influencing the water quality is the small content of dissolved oxygen (DO) in the water body. Meanwhile, the pollution of the water body mainly results from the discharge of organic matter consuming oxygen largely, and ammonia nitrogen should be paid more attention to. [ Conclusion] The research could provide scientific references for the protection of water environment and its pollu- tion control in the mainstream of the Liaohe River.
文摘With development of foreign language education in China, more and more people pay attention to the research of the mainstream EFL teaching styles, which combines the seemingly contradictory points of both traditional and current linguistic theories and use them well in foreign language teaching. With special features, the mainstream EFL teaching style has its advantage and weakness and it needs much improvement in teaching process.
文摘In this paper,the author starts with a discussion of what mainstream linguistics is,in aim of clearly defining mainstream linguistics.Then the author further makes a distinction and comparison between mainstream linguistics and non-mainstream linguistics.In the third part of the paper,the author probes into and reflects on the main criticisms of mainstream linguistics.
文摘In Tanzania 80% of the population live in informal settlements. Most of these settlements are built in areas that are susceptible to extreme weather conditions such as flooding. Such conditions have significantly contributed to the destruction of housing stock and other valuable properties. There is considerable awareness amongst people living in the informal settlements, government representatives and other key stakeholders about the various flood risks affecting informal settlements. Based on this understanding, several attempts to minimize flood risks have been initiated in Dar es Salaam, Tanzania, yet these initiatives have largely failed to deliver the desired impacts. This article aims to investigate core reasons for this through a case study of Keko Machungwa Informal settlement in Dar es Salaam City. The study explores the extent to which mainstreaming of disaster risk reduction (DRR) in housing development in informal settlements has been considered and implemented, and recommends measures for improvement. Key methods employed for the research included physical observation, household interviews, mapping, photographing, and in-depth interviews. Overall, the study found that mainstreaming of DRR in housing development was hardly practiced at the household level, as houses were predominantly being built without resistant building materials and supervision of relevant professionals. In order to mainstream DRR in housing development in informal settlements, it is recommended that mainstreaming DRR be embedded in laws and policies, highly vulnerable parts of the settlement be declared protected wetland and that the government direct its efforts towards regulating, controlling and monitoring the housing development sector. That letter can be achieved by emphasizing the use of flood resistant building materials and establishing resilient infrastructures for flood mitigation in every flood prone informal settlement.
文摘[ Objective] To explore the effect of expansion temperature on the release of seven kinds of Hoffmann components (CO, NNK, NH3, HCN,, BaP, crotonaldehyde and phenol) from the mainstream smoke of cigarette. [ Method] The release amount of seven kinds of Hoffmann com-ponents from the mainstream smoke of cigarettes which were prepared from the cut tobacco treated under different expansion temperatures was de-termined. [ Result] Under the same expansion model, the temperature change produced certain impact on the release amount of NH~, phenol and BAP, while had no significant influence on that of CO, NNK, HCN and crotonaldehyde; under CO2 expansion model, the release amount of seven Hoffmann components was small; the reduction of expansion temperature was good for lowering the harmful index of cigarette to a certain extent. [ Conclusion] The study provides basis for optimizing the technical parameters of producinq less harmful cigarette.
文摘The adoption and use of social media has played a major role in the changes in journalists’ work. The use of these new means has become indispensable to the daily tasks and work of journalists in most news organizations. It is no longer possible to bypass these means when it comes to searching for information and news, or in production, publishing, distribution and marketing, or even in interaction with the public. The characteristics of ease, speed, immediacy, interactivity, and being free of charge that characterize them, have made them a useful technological tool, which is influential and necessary not only for the future of the journalist’s career but also for the future of the news organization itself. With the growing number of users of social media around the world, journalists and news organizations have found additional access, more important than previous channels, to access additional sources that help them market and interact with their work in a new dynamic environment completely different from previous communication models, and put audience activity at the forefront. In this study, which is part of the Technology Acceptance Model (TAM), the author tries to understand and analyze the factors of adoption and use of social media as a new technological tool by Bahraini journalists and to identify their new role in the changes in journalism. In addition, the study attempts to examine the implications in relation to the future of the press profession and the economic model of the news organization. The results showed a clear adoption and an increased use of social media by journalists, who consider it a key element in the development of journalism, and an inevitable strategic choice for the future of the news organization. They also expressed their full awareness of the problems surrounding the issue of precision and credibility of news accessed through social media.
文摘The gender mainstreaming policy has developed with the change of culture in Taiwan from 2001 to 2012. Based on literature review, this paper discusses the change of culture and the development of gender mainstreaming policy with "Gender at Work Framework" to explain the difference between change at the formal, organizational level and change at the informal and personal level for addressing the root causes of gender equality. This research finds that to achieve gender mainstreaming policy goal, the government has to foster robust, and sound cultural basis for the society.