In retrospect,Africa has travelled an“S”curve over the past 40 years on itsroad of economic development.The year 1994 can be regarded as a turning pointfor the better with an annual growth rate of 2.8%.The following...In retrospect,Africa has travelled an“S”curve over the past 40 years on itsroad of economic development.The year 1994 can be regarded as a turning pointfor the better with an annual growth rate of 2.8%.The following two years 1995and 1996 witnessed further improvement with growth rates of 3.7% and 3.96%respectively.These were the highest rates in the past 20 years, surpassing that展开更多
The majority of African countries won their political independence in the 1960s.Since then,they have been making relentless efforts to develop their economiesand raise their people’s living standards,and have achieve...The majority of African countries won their political independence in the 1960s.Since then,they have been making relentless efforts to develop their economiesand raise their people’s living standards,and have achieved successes in varying de-grees.展开更多
Welcome to high summer[盛夏],dear CE:Teens readers!When we are young, summer can be a magical[不可思议的] time, free from many of the more stressful[紧迫的] parts of our lives,namely,school! But summer can also be a c...Welcome to high summer[盛夏],dear CE:Teens readers!When we are young, summer can be a magical[不可思议的] time, free from many of the more stressful[紧迫的] parts of our lives,namely,school! But summer can also be a confusing[混乱的] time of year When faced with a long holiday,after we have caught up with friends we haven’t seen for a long time, slept late for the twentieth展开更多
In China the desire to be taller is high （excuse the pun）, despite people＇s genetic make-up. It＇s a desire driven by the sheer volume of folk competing for partners, promotions and prime job offerings, where any a...In China the desire to be taller is high （excuse the pun）, despite people＇s genetic make-up. It＇s a desire driven by the sheer volume of folk competing for partners, promotions and prime job offerings, where any advantage is sought in order to get a foot in the door. And with the vast numbers of job seekers competing for positions, recruiters behind those doors can afford to be picky. The word on the street is height means rapid advancement through the ranks. Many young professionals hold the common belief that taller people have more opportunity for promotion in the desperate climb up the corporate ladder.展开更多
There are major concerns over both the security of energy supplies （declining supplies and political control） and the en- vironmental costs associated with energy generation and use. The global consumption of carbon...There are major concerns over both the security of energy supplies （declining supplies and political control） and the en- vironmental costs associated with energy generation and use. The global consumption of carbon-containing fossil fuels for heat, electricity, transport and the manufacture of chemicals is not sustainable. This has promulgated a great interest in various forms of renewable energy and the imposition,展开更多
Doping metal ions offer a promising strategy to tune the intrinsic and surface properties of BiVO_(4)for enhanced photoelectrochemical(PEC)activity.Given this,experimental and theoretical studies on cadmium(Cd)doping ...Doping metal ions offer a promising strategy to tune the intrinsic and surface properties of BiVO_(4)for enhanced photoelectrochemical(PEC)activity.Given this,experimental and theoretical studies on cadmium(Cd)doping to BiVO_(4)photoanode were studied for PEC water splitting applications.The spectroscopic and PEC results indicate that the substitution of Cd at Bi lattice sites causes the reduction in the valence state of V^(5+)to V4+that creates hole trap states below the Fermi level of BiVO_(4).The introduced hole trap states at the BiVO_(4)surface suppress the charge recombination and provide effective hole transfer sites for the facile water oxidation reactions.The CdBiVO_(4)exhibited significantly higher photocurrent compared to the pristine BiVO_(4)reaching 3.5 mA cm^(-2)(with a hole scavenger)at 1.23 V vs RHE.Furthermore,doping increases the carrier density in the bulk of BiVO_(4)leading to improved charge separation,and charge transfer while reducing the hole transfer resistance at the interface.The Cd-doped BiVO_(4)exhibited a charge separation efficiency of 80%and with a 90%of overall water splitting faradaic efficiency.Importantly,the results of this work propose the advantages of doping metal ions at Bi lattice sites in BiVO_(4)for improved PEC activity.展开更多
Ningxia aspires to develop its wine industry The storage cellar of Ningxia Xixia King Winery (Group) Co.Ltd.is filled with the expected large oak barrels of wine.What’s unexpected are the names of international celeb...Ningxia aspires to develop its wine industry The storage cellar of Ningxia Xixia King Winery (Group) Co.Ltd.is filled with the expected large oak barrels of wine.What’s unexpected are the names of international celebrities and politicians,the former German Defense Minister Rudolf Albert Scharping and former Argentina Transportation Minister Jermyn Kamllows for instance,tagged on specific barrels.展开更多
Countries face disputes while attempting to take positive actions on climate change The marathon-like UN Climate Change Conference in Cancun accurately reflected the difficulty of coming to a consensus on this content...Countries face disputes while attempting to take positive actions on climate change The marathon-like UN Climate Change Conference in Cancun accurately reflected the difficulty of coming to a consensus on this contentious issue. Instead of reaching high-profile展开更多
Despite donor countries’ unmet commitments, developing nations vow to help each other end hunger and poverty "The rich will do anything for the poor but get off their backs." At least that is what Karl Marx...Despite donor countries’ unmet commitments, developing nations vow to help each other end hunger and poverty "The rich will do anything for the poor but get off their backs." At least that is what Karl Marx, the 19th century展开更多
China looks to strategically important emerging industries for innovation-driven economic growthc hina will soon announce a decision to rev up seven strategically impor- tant emerging industries,said the
文摘In retrospect,Africa has travelled an“S”curve over the past 40 years on itsroad of economic development.The year 1994 can be regarded as a turning pointfor the better with an annual growth rate of 2.8%.The following two years 1995and 1996 witnessed further improvement with growth rates of 3.7% and 3.96%respectively.These were the highest rates in the past 20 years, surpassing that
文摘The majority of African countries won their political independence in the 1960s.Since then,they have been making relentless efforts to develop their economiesand raise their people’s living standards,and have achieved successes in varying de-grees.
文摘Welcome to high summer[盛夏],dear CE:Teens readers!When we are young, summer can be a magical[不可思议的] time, free from many of the more stressful[紧迫的] parts of our lives,namely,school! But summer can also be a confusing[混乱的] time of year When faced with a long holiday,after we have caught up with friends we haven’t seen for a long time, slept late for the twentieth
文摘In China the desire to be taller is high （excuse the pun）, despite people＇s genetic make-up. It＇s a desire driven by the sheer volume of folk competing for partners, promotions and prime job offerings, where any advantage is sought in order to get a foot in the door. And with the vast numbers of job seekers competing for positions, recruiters behind those doors can afford to be picky. The word on the street is height means rapid advancement through the ranks. Many young professionals hold the common belief that taller people have more opportunity for promotion in the desperate climb up the corporate ladder.
文摘There are major concerns over both the security of energy supplies （declining supplies and political control） and the en- vironmental costs associated with energy generation and use. The global consumption of carbon-containing fossil fuels for heat, electricity, transport and the manufacture of chemicals is not sustainable. This has promulgated a great interest in various forms of renewable energy and the imposition,
基金the support of the Natural Sciences and Engineering Research Council of Canada(NSERC)Tier 1 Canada Research Chair in Green Hydrogen Production,the Québec Ministère de l'Économie,de l'Innovation et de l'Énergie(MEIE)[Développement de catalyseurs et d'électrodes innovants,àfaibles coûts,performants et durables pour la production d'hydrogène vert,funding reference number 00393501]。
文摘Doping metal ions offer a promising strategy to tune the intrinsic and surface properties of BiVO_(4)for enhanced photoelectrochemical(PEC)activity.Given this,experimental and theoretical studies on cadmium(Cd)doping to BiVO_(4)photoanode were studied for PEC water splitting applications.The spectroscopic and PEC results indicate that the substitution of Cd at Bi lattice sites causes the reduction in the valence state of V^(5+)to V4+that creates hole trap states below the Fermi level of BiVO_(4).The introduced hole trap states at the BiVO_(4)surface suppress the charge recombination and provide effective hole transfer sites for the facile water oxidation reactions.The CdBiVO_(4)exhibited significantly higher photocurrent compared to the pristine BiVO_(4)reaching 3.5 mA cm^(-2)(with a hole scavenger)at 1.23 V vs RHE.Furthermore,doping increases the carrier density in the bulk of BiVO_(4)leading to improved charge separation,and charge transfer while reducing the hole transfer resistance at the interface.The Cd-doped BiVO_(4)exhibited a charge separation efficiency of 80%and with a 90%of overall water splitting faradaic efficiency.Importantly,the results of this work propose the advantages of doping metal ions at Bi lattice sites in BiVO_(4)for improved PEC activity.
文摘Ningxia aspires to develop its wine industry The storage cellar of Ningxia Xixia King Winery (Group) Co.Ltd.is filled with the expected large oak barrels of wine.What’s unexpected are the names of international celebrities and politicians,the former German Defense Minister Rudolf Albert Scharping and former Argentina Transportation Minister Jermyn Kamllows for instance,tagged on specific barrels.
文摘Countries face disputes while attempting to take positive actions on climate change The marathon-like UN Climate Change Conference in Cancun accurately reflected the difficulty of coming to a consensus on this contentious issue. Instead of reaching high-profile
文摘Despite donor countries’ unmet commitments, developing nations vow to help each other end hunger and poverty "The rich will do anything for the poor but get off their backs." At least that is what Karl Marx, the 19th century
文摘China looks to strategically important emerging industries for innovation-driven economic growthc hina will soon announce a decision to rev up seven strategically impor- tant emerging industries,said the
