This study explored the factors influencing cooperative innovation in environmentally friendly agricultural biotechnology in China.First,we constructed an evolutionary game model comprising the factors of net income o...This study explored the factors influencing cooperative innovation in environmentally friendly agricultural biotechnology in China.First,we constructed an evolutionary game model comprising the factors of net income of cooperative innovation,net income of independent innovation,market constraints,and government subsidies.Using MATLAB simulation,we assigned different values to the aforementioned variables to explore the evolutionary trend of innovators’willingness to cooperate.Results showed that when the values of net income of cooperative innovation,net income of independent innovation,market constraints,and government subsidies exceeded the threshold,innovators’willingness to cooperate was significantly enhanced.Furthermore,the proportion of innovators who cooperated with others gradually increased to 100%;otherwise,it gradually decreased to 0%.Comparing the simulation curve with the real evolution curve of cooperative innovation in agricultural biotechnology in China,we found that the gradual decline in the willingness to cooperate could be due to insufficient subsidies for cooperative innovation,low income from cooperative innovation,weak profitability of innovators,and weak market constraints.展开更多
With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cit...With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cities,the commuting space of 11 primary and secondary schools in Bajiao Street is analyzed through literature analysis and field research methods.Firstly,the relevant literature on school commuting space is sorted out,and the characteristics of school commuting space are summarized,including transportation,landscape,culture,leisure,and security.Secondly,the characteristics of commuting space of primary and secondary schools in Bajiao Street are analyzed from three aspects:in front of the school gate,path space,and node space.This paper aims to provide reference and guidance for the future construction of children’s walking school commuting and promote the construction of a child friendly city.展开更多
The control of carbon emissions and energy conservation,and environmental protection are hot spots of global concern.In this paper,phase change paraffin wax is applied to porous materials for adsorption and storage,an...The control of carbon emissions and energy conservation,and environmental protection are hot spots of global concern.In this paper,phase change paraffin wax is applied to porous materials for adsorption and storage,and nature’s eco-friendly materials are selected as the porous matrix to propose an eco-friendly phase change concrete using eco-friendly materials as raw materials.It was obtained that the strength of the phase change concrete utilizing environmentally friendly materials was 25.4%to 36.8%lower than that of ordinary concrete,while some of the phase change light aggregates were found to produce slip damage with the cement paste in the damage study.By constructing a small-sized test room for thermal properties,we obtained a phase change concrete that utilizes environmentally friendly materials to control the temperature better than the commonly studied phase change concrete,with a peak temperature drop of up to 2.6℃ in the phase change test room compared to the normal test room and a delay in the peak temperature.展开更多
With the exploration and development of deep and ultra-deep oil and gas,high torque and high friction during the drilling of deep and ultra-deep wells become one of the key issues affecting drilling safety and drillin...With the exploration and development of deep and ultra-deep oil and gas,high torque and high friction during the drilling of deep and ultra-deep wells become one of the key issues affecting drilling safety and drilling speed.Meanwhile,the high temperature and high salt problem in deep formations is prominent,which poses a major challenge to the lubricity of drilling fluids under high temperature and high salt.This paper reports an organic borate ester SOP as an environmentally friendly drilling fluid lubricant.The performance evaluation results show that when 1%lubricant SOP is added to the fresh water-based mud,the lubrication coefficient decreases from 0.631 to 0.046,and the reduction rate of lubrication coefficient is 92.7%.Under the conditions of 210℃ and 30%NaCl,the reduction rate of lubricating coefficient of the base slurry with 1%SOP was still remain 81.5%.After adding 1%SOP,the wear volume decreased by 94.11%compared with the base slurry.The contact resistance experiment during the friction process shows that SOP can form a thick adsorption film on the friction surface under high temperature and high salt conditions,thus effectively reducing the friction resistance.Molecular dynamics simulation shows that lubricant SOP can be physically adsorbed on the surface of drilling tool and borehole wall through hydrogen bond and van der Waals force.XPS analysis further shows that SOP adsorbs on the friction surface and reacts with metal atoms on the friction surface to form a chemically reactive film.Therefore,under high temperature and high salt conditions,the synergistic effect of physical adsorption film and chemical reaction film effectively reduces the frictional resistance and wear of the friction surface.In addition,SOP is non-toxic and easy to degrade.Therefore,SOP is a highly effective and environmentally friendly lubricant in high temperature and high salt drilling fluid.展开更多
Difenoconazole(DIF)is a representative variety of broad-spectrum triazole fungicides and liposoluble pesticides.However,the water solubility of DIF is so poor that its application is limited in plant protection.In add...Difenoconazole(DIF)is a representative variety of broad-spectrum triazole fungicides and liposoluble pesticides.However,the water solubility of DIF is so poor that its application is limited in plant protection.In addition,the conventional formulations of DIF always contain abundant organic solvents,which may cause pollution of the environment.In this study,two DIF/cyclodextrins(CDs)inclusion complexes(ICs)were successfully prepared,which were DIF/β-CD IC and DIF/hydroxypropyl-β-CD IC(DIF/HP-β-CD IC).The effect of cyclodextrins on the water solubility and the antifungal effect of liposoluble DIF pesticide were investigated.According to the phase solubility test,the molar ratio and apparent stability constant of ICs were obtained.Fourier transform infrared spectroscopy,thermal gravity analysis,X-ray diffraction and scanning electron microscopy were used systematically to characterize the formation and characteristics of ICs.The results noted that DIF successfully entered the cavities of two CDs.In addition,the antifungal effect test proved the better performance of DIF/HP-β-CD IC,which exceeded that of DIF emulsifiable concentrate.Therefore,our study provides informative direction for the intelligent use of liposoluble pesticides with cyclodextrins to develop water-based environmentally friendly formulations.展开更多
In order to actively implement the Convention on Biological Diversity and help Shenzhen build a "park city" and a model of beautiful China, the concepts of landscape ecology, landscape urbanism and bio frien...In order to actively implement the Convention on Biological Diversity and help Shenzhen build a "park city" and a model of beautiful China, the concepts of landscape ecology, landscape urbanism and bio friendly city are introduced to build an evaluation system for biodiversity friendly parks in Longhua District, and explore the relationship between "bio friendly living space" and "city". According to the evaluation system, the Guanlan Printmaking Base scores a total of 273 points, which is rated as a relatively friendly level. In order to coordinate the development between the city and the biosphere and contribute to the goal of building a biodiversity based urban park, the construction of a biodiversity friendly park in Guanlan Printmaking Base is carried out in terms of comprehensive design, plant community construction and biodiversity friendly facilities construction according to the construction principles of biological priority guidance, functional integration and diversification, respect for the park's regionality, and valuing the reachability of natural space.展开更多
Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short ...Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short video on the communication of Shandong tourism image.The research mainly included two aspects:fan persona features and interactive effects.Through comparative study,it will provide a reference for the operation team of“Friendly Shandong”official account to spread the tourism image of Shandong with different platforms.展开更多
Dear Dale,I'm glad to hear from you.You asked me something about how to make friends.In my opinion,you can make friends in the following principles.First of all,you must be friendly to others if you want to make f...Dear Dale,I'm glad to hear from you.You asked me something about how to make friends.In my opinion,you can make friends in the following principles.First of all,you must be friendly to others if you want to make friends with them.Everyone can be in trouble,so at any time,you should be friendly to others.In this way,you will have a lot of friends.展开更多
The eco-friendly cotton bags are anticipated to overtake plastic bags in the retail sector during the forecast period.The increasing availability of decorated cotton bags is inciting people to increasingly adopt cotto...The eco-friendly cotton bags are anticipated to overtake plastic bags in the retail sector during the forecast period.The increasing availability of decorated cotton bags is inciting people to increasingly adopt cotton bags.Cotton bags have high printability&shelf appeal as compared to plastic bags.展开更多
FROM May 5 to 10,Chinese President Xi Jinping paid state visits to France,Serbia,and Hungary.Being his first European trip in about five years,it consolidated China’s relationships with the three countries and Europe...FROM May 5 to 10,Chinese President Xi Jinping paid state visits to France,Serbia,and Hungary.Being his first European trip in about five years,it consolidated China’s relationships with the three countries and Europe as a whole.The four states looked back on the history of their friendships,signed multiple cooperation agreements,and reached a consensus on promoting stable and sound development of China-Europe relations.Great Minds Think Alike Upon his arrival in Paris on May 5,President Xi Jinping received a warm welcome in Chinese from Gabriel Attal,France’s youngest ever modern prime minister.展开更多
The ways and technology of synthesis of alcohol, ether, ester, amine ester, lactone, polyester, carbamide and diamond based on CO2 were explored. Using CO2 as potential organic carbon resources not only solves environ...The ways and technology of synthesis of alcohol, ether, ester, amine ester, lactone, polyester, carbamide and diamond based on CO2 were explored. Using CO2 as potential organic carbon resources not only solves environmental problem, but also eases shortage of resources.展开更多
Hello,I am Allen,a primary school student from No.2 Experimental Primary School in Doumen District,Zhuhai,Guangdong Province.I am an active and outgoing person who loves making friends.Allow me to introduce you to my ...Hello,I am Allen,a primary school student from No.2 Experimental Primary School in Doumen District,Zhuhai,Guangdong Province.I am an active and outgoing person who loves making friends.Allow me to introduce you to my five good friends:Nick,Jack,Alex,Tina,and Lily.展开更多
It is very easy for an African living in Africa to be misled into believing that the China-Africa friendship is superficial.In fact,with so much of information reaching Africa about China-Africa cooperation being targ...It is very easy for an African living in Africa to be misled into believing that the China-Africa friendship is superficial.In fact,with so much of information reaching Africa about China-Africa cooperation being targeted at undermining the friendly relations enjoyed by the two sides and the e!orts to build a China-Africa community with a shared future,this in a way is not surprising.展开更多
A kind of environmental friendly anodizing routine for AZ91D magnesium alloy,based on an alkaline borate-potassium acid phthalate(KAP) electrolyte,was studied.The effect of KAP on the properties of the anodized film...A kind of environmental friendly anodizing routine for AZ91D magnesium alloy,based on an alkaline borate-potassium acid phthalate(KAP) electrolyte,was studied.The effect of KAP on the properties of the anodized film was investigated by scanning electron microscopy(SEM),X-ray diffraction(XRD),energy dispersive spectrometry(EDS),potentiodynamic polarization and electrochemical impedance spectroscopy(EIS),respectively.The results showed that the anodizing process,surface morphology,thickness,phase structure and corrosion resistance of the anodized film were strongly dependent on the concentration of KAP.In the presence of adequate KAP,a compact and smooth anodized film with excellent corrosion resistance was obtained.展开更多
在The American Heritage Dictionary of the English Language的第4版中,我们可以发现friendly一词有一新的义项:4a.User-friendly.b.Informal Easy to understand or use for a specified agent.Often used in combination:a reader-f...在The American Heritage Dictionary of the English Language的第4版中,我们可以发现friendly一词有一新的义项:4a.User-friendly.b.Informal Easy to understand or use for a specified agent.Often used in combination:a reader-friendly novel;a consumerfriendly policy.展开更多
The plasticizer is an important polymer material additive.Non-toxic and environmentally friendly plasticizers are developed recently in order to decrease fossil fuel reserves,serious environmental pollution and the to...The plasticizer is an important polymer material additive.Non-toxic and environmentally friendly plasticizers are developed recently in order to decrease fossil fuel reserves,serious environmental pollution and the toxicity of phthalate esters.In this study,a new,efficient and environmentally friendly plasticizer of hydrogenated rosin dodecyl ester was prepared by an esterification reaction of hydrogenated rosin and dodecanol.The influences of different reaction conditions(including different catalysts,the catalyst concentration,the ratio of the reactants,reaction temperature,and reaction time)on the esterification yield are examined and discussed.Hydrogenated rosin dodecyl ester with 71.8%yield was synthesized under the optimized reaction conditions(1:0.8 molar ratio of rosin to dodecanol,1 mol%tetrabutyl titanate concentration,and 210℃for 6 h).The esterification reaction is a second-order reaction,and kinetic calculations showed that the activation energy is 39.77 KJ·mol^(−1).The structure of the hydrogenated rosin dodecyl ester was confirmed by FT-IR spectroscopy and^(13)C NMR spectrum.Besides,the thermal stability of target product(hydrogenated rosin dodecyl ester)was also tested by thermal gravimetric analysis(TGA),which showed a good thermal stability.展开更多
The demand for non-toxic and biodegradable shale inhibitors is growing in the drilling industry.In this paper,the effect of notoginsenoside(NS)as a new,environmentally friendly inhibitor of shale hydration is systemat...The demand for non-toxic and biodegradable shale inhibitors is growing in the drilling industry.In this paper,the effect of notoginsenoside(NS)as a new,environmentally friendly inhibitor of shale hydration is systematically studied for the first time.The inhibition performance of NS was evaluated via inhibition evaluation tests,including mud ball immersion tests,linear expansion tests,shale rolling recovery tests,and compressive strength tests.The inhibition mechanism of NS was analyzed using Fourier transform infrared spectroscopy(FTIR),contact angle measurements,particle size distribution determination,thermogravimetric analysis(TGA),and scanning electron microscopy(SEM).The experimental results demonstrate that NS is able to adhere to the clay surface,forming a hydrophobic film that prevents the entry of water molecules and inhibiting the hydration dispersion of the clay.Because of this,NS can maintain the original state of bentonite pellets in water,which can effectively reduce the swelling rate of bentonite,increase the recovery rate of shale drill cuttings,maintain the strength of the shale,and therefore maintain the stability of the borehole wall during drilling.In addition,NS is non-toxic,degradable,and compatible with water-based drilling fluids.The above advantages make NS a promising candidate for use as an environmentally friendly shale inhibitor.展开更多
An anodizing process, based on environmental friendly electrolyte solutions has been studied on AZ 91 magnesium alloys by using three types of electrolytes: the first is based on sodium silicate, the second on sodium ...An anodizing process, based on environmental friendly electrolyte solutions has been studied on AZ 91 magnesium alloys by using three types of electrolytes: the first is based on sodium silicate, the second on sodium hydroxide-boric acid-borax and the third on sodium silicate- potassium hydroxide-sodium carbonate-sodium tetra borate. A pretreatment including fluoride activation was applied before the anodizing process. It was found that the anodic film thickness increases as current density or anodizing voltage increases. It is also increased with deposition time until the deposition stops due to the formation of a thick anodic film. Optimization of the anodizing conditions - current density and deposition time- was made for each electrolyte. Characterization of anodizing layer was achieved by determination of surface morphology, microstructure, phase analysis, coat thickness, adhesion and corrosion resistance. In all cases, excellent adhesion and corrosion resistance was obtained. A corrosion efficiency ranging from 94% to 97% was reached;the highest value corresponding to the third electrolyte.展开更多
A series of acetate ionic liquids were synthesized using a typical two‐step method.The ionic liquids were used as environmentally benign catalysts in the production of propylene glycol ethers from propylene oxide and...A series of acetate ionic liquids were synthesized using a typical two‐step method.The ionic liquids were used as environmentally benign catalysts in the production of propylene glycol ethers from propylene oxide and alcohols under mild conditions.The basic strengths of the ionic liquids were evaluated by determination of their Hammett functions,obtained using ultraviolet‐visible spectroscopy,and the relationship between their catalytic activities and basicities was established.The catalytic efficiencies of the ionic liquids were higher than that of the traditional basic catalyst NaOH.This can be attributed to the involvement of a novel reaction mechanism when these ionic liquids are used.A possible electrophilic‐nucleophilic dual activation mechanism was proposed and confirmed using electrospray ionization quadrupole time‐of‐flight mass spectrometry.In addition,the effects of significant reaction parameters such as concentration of catalyst,molar ratio of alcohol to propylene oxide,reaction temperature,and steric hindrance of the alcohol were investigated in detail.展开更多
基金funded by National Social Science Fund the Evolution of Japan’s Food Security Policy and Its Enlightenment to China[Grant No.22CSS016].
文摘This study explored the factors influencing cooperative innovation in environmentally friendly agricultural biotechnology in China.First,we constructed an evolutionary game model comprising the factors of net income of cooperative innovation,net income of independent innovation,market constraints,and government subsidies.Using MATLAB simulation,we assigned different values to the aforementioned variables to explore the evolutionary trend of innovators’willingness to cooperate.Results showed that when the values of net income of cooperative innovation,net income of independent innovation,market constraints,and government subsidies exceeded the threshold,innovators’willingness to cooperate was significantly enhanced.Furthermore,the proportion of innovators who cooperated with others gradually increased to 100%;otherwise,it gradually decreased to 0%.Comparing the simulation curve with the real evolution curve of cooperative innovation in agricultural biotechnology in China,we found that the gradual decline in the willingness to cooperate could be due to insufficient subsidies for cooperative innovation,low income from cooperative innovation,weak profitability of innovators,and weak market constraints.
基金National Natural Science Foundation of China(51708004)Beijing Youth Teaching Elite Team Construction Project(108051360023XN261)North China University of Technology Yuyou Talent Training Program(215051360020XN160/009).
文摘With the continuous promotion of the construction of child friendly cities,the school commuting space is an important component of the construction of child friendly roads.Based on the background of child friendly cities,the commuting space of 11 primary and secondary schools in Bajiao Street is analyzed through literature analysis and field research methods.Firstly,the relevant literature on school commuting space is sorted out,and the characteristics of school commuting space are summarized,including transportation,landscape,culture,leisure,and security.Secondly,the characteristics of commuting space of primary and secondary schools in Bajiao Street are analyzed from three aspects:in front of the school gate,path space,and node space.This paper aims to provide reference and guidance for the future construction of children’s walking school commuting and promote the construction of a child friendly city.
基金Thanks to the Shandong Science and Technology Development Project(2013YD02043)and Shandong University of Science and Technology Science and Technology Innovation Program for their support.
文摘The control of carbon emissions and energy conservation,and environmental protection are hot spots of global concern.In this paper,phase change paraffin wax is applied to porous materials for adsorption and storage,and nature’s eco-friendly materials are selected as the porous matrix to propose an eco-friendly phase change concrete using eco-friendly materials as raw materials.It was obtained that the strength of the phase change concrete utilizing environmentally friendly materials was 25.4%to 36.8%lower than that of ordinary concrete,while some of the phase change light aggregates were found to produce slip damage with the cement paste in the damage study.By constructing a small-sized test room for thermal properties,we obtained a phase change concrete that utilizes environmentally friendly materials to control the temperature better than the commonly studied phase change concrete,with a peak temperature drop of up to 2.6℃ in the phase change test room compared to the normal test room and a delay in the peak temperature.
基金financially supported by National Natural Science Foundation of China(No.52074330)National Natural Science Foundation of China Major Projects(No.51991361).
文摘With the exploration and development of deep and ultra-deep oil and gas,high torque and high friction during the drilling of deep and ultra-deep wells become one of the key issues affecting drilling safety and drilling speed.Meanwhile,the high temperature and high salt problem in deep formations is prominent,which poses a major challenge to the lubricity of drilling fluids under high temperature and high salt.This paper reports an organic borate ester SOP as an environmentally friendly drilling fluid lubricant.The performance evaluation results show that when 1%lubricant SOP is added to the fresh water-based mud,the lubrication coefficient decreases from 0.631 to 0.046,and the reduction rate of lubrication coefficient is 92.7%.Under the conditions of 210℃ and 30%NaCl,the reduction rate of lubricating coefficient of the base slurry with 1%SOP was still remain 81.5%.After adding 1%SOP,the wear volume decreased by 94.11%compared with the base slurry.The contact resistance experiment during the friction process shows that SOP can form a thick adsorption film on the friction surface under high temperature and high salt conditions,thus effectively reducing the friction resistance.Molecular dynamics simulation shows that lubricant SOP can be physically adsorbed on the surface of drilling tool and borehole wall through hydrogen bond and van der Waals force.XPS analysis further shows that SOP adsorbs on the friction surface and reacts with metal atoms on the friction surface to form a chemically reactive film.Therefore,under high temperature and high salt conditions,the synergistic effect of physical adsorption film and chemical reaction film effectively reduces the frictional resistance and wear of the friction surface.In addition,SOP is non-toxic and easy to degrade.Therefore,SOP is a highly effective and environmentally friendly lubricant in high temperature and high salt drilling fluid.
文摘Difenoconazole(DIF)is a representative variety of broad-spectrum triazole fungicides and liposoluble pesticides.However,the water solubility of DIF is so poor that its application is limited in plant protection.In addition,the conventional formulations of DIF always contain abundant organic solvents,which may cause pollution of the environment.In this study,two DIF/cyclodextrins(CDs)inclusion complexes(ICs)were successfully prepared,which were DIF/β-CD IC and DIF/hydroxypropyl-β-CD IC(DIF/HP-β-CD IC).The effect of cyclodextrins on the water solubility and the antifungal effect of liposoluble DIF pesticide were investigated.According to the phase solubility test,the molar ratio and apparent stability constant of ICs were obtained.Fourier transform infrared spectroscopy,thermal gravity analysis,X-ray diffraction and scanning electron microscopy were used systematically to characterize the formation and characteristics of ICs.The results noted that DIF successfully entered the cavities of two CDs.In addition,the antifungal effect test proved the better performance of DIF/HP-β-CD IC,which exceeded that of DIF emulsifiable concentrate.Therefore,our study provides informative direction for the intelligent use of liposoluble pesticides with cyclodextrins to develop water-based environmentally friendly formulations.
文摘In order to actively implement the Convention on Biological Diversity and help Shenzhen build a "park city" and a model of beautiful China, the concepts of landscape ecology, landscape urbanism and bio friendly city are introduced to build an evaluation system for biodiversity friendly parks in Longhua District, and explore the relationship between "bio friendly living space" and "city". According to the evaluation system, the Guanlan Printmaking Base scores a total of 273 points, which is rated as a relatively friendly level. In order to coordinate the development between the city and the biosphere and contribute to the goal of building a biodiversity based urban park, the construction of a biodiversity friendly park in Guanlan Printmaking Base is carried out in terms of comprehensive design, plant community construction and biodiversity friendly facilities construction according to the construction principles of biological priority guidance, functional integration and diversification, respect for the park's regionality, and valuing the reachability of natural space.
基金Social Science Planning Research Project of Shandong Province(22CLYJ34)Key Project of Shandong Art Science(23QR03280040)+1 种基金Social Science Project of Tai’an City(23YB061)First-class Undergraduate Courses of Tourism Markeing of Taishan University.
文摘Taking“Friendly Shandong”official account as an example,the relevant data of the account on the four platforms of Tiktok,Kwai,Bilibili and Little Red Book were comparatively analyzed to study the influence of short video on the communication of Shandong tourism image.The research mainly included two aspects:fan persona features and interactive effects.Through comparative study,it will provide a reference for the operation team of“Friendly Shandong”official account to spread the tourism image of Shandong with different platforms.
文摘Dear Dale,I'm glad to hear from you.You asked me something about how to make friends.In my opinion,you can make friends in the following principles.First of all,you must be friendly to others if you want to make friends with them.Everyone can be in trouble,so at any time,you should be friendly to others.In this way,you will have a lot of friends.
文摘The eco-friendly cotton bags are anticipated to overtake plastic bags in the retail sector during the forecast period.The increasing availability of decorated cotton bags is inciting people to increasingly adopt cotton bags.Cotton bags have high printability&shelf appeal as compared to plastic bags.
文摘FROM May 5 to 10,Chinese President Xi Jinping paid state visits to France,Serbia,and Hungary.Being his first European trip in about five years,it consolidated China’s relationships with the three countries and Europe as a whole.The four states looked back on the history of their friendships,signed multiple cooperation agreements,and reached a consensus on promoting stable and sound development of China-Europe relations.Great Minds Think Alike Upon his arrival in Paris on May 5,President Xi Jinping received a warm welcome in Chinese from Gabriel Attal,France’s youngest ever modern prime minister.
文摘The ways and technology of synthesis of alcohol, ether, ester, amine ester, lactone, polyester, carbamide and diamond based on CO2 were explored. Using CO2 as potential organic carbon resources not only solves environmental problem, but also eases shortage of resources.
文摘Hello,I am Allen,a primary school student from No.2 Experimental Primary School in Doumen District,Zhuhai,Guangdong Province.I am an active and outgoing person who loves making friends.Allow me to introduce you to my five good friends:Nick,Jack,Alex,Tina,and Lily.
文摘It is very easy for an African living in Africa to be misled into believing that the China-Africa friendship is superficial.In fact,with so much of information reaching Africa about China-Africa cooperation being targeted at undermining the friendly relations enjoyed by the two sides and the e!orts to build a China-Africa community with a shared future,this in a way is not surprising.
基金Projects (50771092,21073162) supported by the National Natural Science Foundation of ChinaProject (08JC1421600) supported by the Science and Technology Commission of Shanghai,ChinaProject (2008AZ2018) supported by the Science and Technology Bureau of Jiaxing,China
文摘A kind of environmental friendly anodizing routine for AZ91D magnesium alloy,based on an alkaline borate-potassium acid phthalate(KAP) electrolyte,was studied.The effect of KAP on the properties of the anodized film was investigated by scanning electron microscopy(SEM),X-ray diffraction(XRD),energy dispersive spectrometry(EDS),potentiodynamic polarization and electrochemical impedance spectroscopy(EIS),respectively.The results showed that the anodizing process,surface morphology,thickness,phase structure and corrosion resistance of the anodized film were strongly dependent on the concentration of KAP.In the presence of adequate KAP,a compact and smooth anodized film with excellent corrosion resistance was obtained.
文摘在The American Heritage Dictionary of the English Language的第4版中,我们可以发现friendly一词有一新的义项:4a.User-friendly.b.Informal Easy to understand or use for a specified agent.Often used in combination:a reader-friendly novel;a consumerfriendly policy.
基金the financial support From the Open Fund Project of Key Lab.of Biomass Energy and Material,Jiangsu Province(JSBEM201907)the Ordinary University Young Innovative Talents Project of Guangdong Province(2018KQNCX119)+4 种基金Provincial Science and Technology Planning Projects of Guangdong Province(2017A040405055)Guangdong-Hong Kong Cooperation Project(2017A050506055)Guangdong Provincial Education Department Project(Natural Science,2017KZDXM045)Guangzhou major special project for collaborative innovation of industry,University and research(201604020074)the fund project of Yele Science and Technology Innovation(YL201807).
文摘The plasticizer is an important polymer material additive.Non-toxic and environmentally friendly plasticizers are developed recently in order to decrease fossil fuel reserves,serious environmental pollution and the toxicity of phthalate esters.In this study,a new,efficient and environmentally friendly plasticizer of hydrogenated rosin dodecyl ester was prepared by an esterification reaction of hydrogenated rosin and dodecanol.The influences of different reaction conditions(including different catalysts,the catalyst concentration,the ratio of the reactants,reaction temperature,and reaction time)on the esterification yield are examined and discussed.Hydrogenated rosin dodecyl ester with 71.8%yield was synthesized under the optimized reaction conditions(1:0.8 molar ratio of rosin to dodecanol,1 mol%tetrabutyl titanate concentration,and 210℃for 6 h).The esterification reaction is a second-order reaction,and kinetic calculations showed that the activation energy is 39.77 KJ·mol^(−1).The structure of the hydrogenated rosin dodecyl ester was confirmed by FT-IR spectroscopy and^(13)C NMR spectrum.Besides,the thermal stability of target product(hydrogenated rosin dodecyl ester)was also tested by thermal gravimetric analysis(TGA),which showed a good thermal stability.
基金financially supported by the National Natural Science Foundation of China(Grants 51904328)the Natural Science Foundation of China(Grants 52074330)
文摘The demand for non-toxic and biodegradable shale inhibitors is growing in the drilling industry.In this paper,the effect of notoginsenoside(NS)as a new,environmentally friendly inhibitor of shale hydration is systematically studied for the first time.The inhibition performance of NS was evaluated via inhibition evaluation tests,including mud ball immersion tests,linear expansion tests,shale rolling recovery tests,and compressive strength tests.The inhibition mechanism of NS was analyzed using Fourier transform infrared spectroscopy(FTIR),contact angle measurements,particle size distribution determination,thermogravimetric analysis(TGA),and scanning electron microscopy(SEM).The experimental results demonstrate that NS is able to adhere to the clay surface,forming a hydrophobic film that prevents the entry of water molecules and inhibiting the hydration dispersion of the clay.Because of this,NS can maintain the original state of bentonite pellets in water,which can effectively reduce the swelling rate of bentonite,increase the recovery rate of shale drill cuttings,maintain the strength of the shale,and therefore maintain the stability of the borehole wall during drilling.In addition,NS is non-toxic,degradable,and compatible with water-based drilling fluids.The above advantages make NS a promising candidate for use as an environmentally friendly shale inhibitor.
文摘An anodizing process, based on environmental friendly electrolyte solutions has been studied on AZ 91 magnesium alloys by using three types of electrolytes: the first is based on sodium silicate, the second on sodium hydroxide-boric acid-borax and the third on sodium silicate- potassium hydroxide-sodium carbonate-sodium tetra borate. A pretreatment including fluoride activation was applied before the anodizing process. It was found that the anodic film thickness increases as current density or anodizing voltage increases. It is also increased with deposition time until the deposition stops due to the formation of a thick anodic film. Optimization of the anodizing conditions - current density and deposition time- was made for each electrolyte. Characterization of anodizing layer was achieved by determination of surface morphology, microstructure, phase analysis, coat thickness, adhesion and corrosion resistance. In all cases, excellent adhesion and corrosion resistance was obtained. A corrosion efficiency ranging from 94% to 97% was reached;the highest value corresponding to the third electrolyte.
基金supported by the One Hundred Talent Program of CASthe National Natural Science Foundation of China Petroleum & Chemical Corporation Joint Fund(U1662129)+1 种基金the National Natural Science Foundation of China(91434203)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(QYZDY-SSW-JSC011)~~
文摘A series of acetate ionic liquids were synthesized using a typical two‐step method.The ionic liquids were used as environmentally benign catalysts in the production of propylene glycol ethers from propylene oxide and alcohols under mild conditions.The basic strengths of the ionic liquids were evaluated by determination of their Hammett functions,obtained using ultraviolet‐visible spectroscopy,and the relationship between their catalytic activities and basicities was established.The catalytic efficiencies of the ionic liquids were higher than that of the traditional basic catalyst NaOH.This can be attributed to the involvement of a novel reaction mechanism when these ionic liquids are used.A possible electrophilic‐nucleophilic dual activation mechanism was proposed and confirmed using electrospray ionization quadrupole time‐of‐flight mass spectrometry.In addition,the effects of significant reaction parameters such as concentration of catalyst,molar ratio of alcohol to propylene oxide,reaction temperature,and steric hindrance of the alcohol were investigated in detail.