FCC dry gas contains a large amount of ethylene. It is used by most of the refineries in China as fuel or simply burned in atmosphere. Few refineries make good use of the dry gas, so the precious ethylene resource in ...FCC dry gas contains a large amount of ethylene. It is used by most of the refineries in China as fuel or simply burned in atmosphere. Few refineries make good use of the dry gas, so the precious ethylene resource in the dry gas is wasted. In this article, the possibility of catalytic conversion of ethylene to C3, C4, and some high molecular weight hydrocarbons in a fixed bed micro-reactor using LTB-1 catalyst, with pure ethylene as feedstock was studied. Effects of reaction temperature, reaction pressure, and feedstock flow rate, on the conversion of ethylene and the distribution of products were investigated to determine the proper reaction parameters to be used in practice. Good results indicate that this study may provide a new way of using the ethylene resource in the FCC dry gas.展开更多
The oligomerization of ethylene in FCC dry gas over HZSM-5 catalyst with different Si/A12 ratios was studied. The effect of acid density of catalyst on the oligomerization of ethylene was discussed. By increasing the ...The oligomerization of ethylene in FCC dry gas over HZSM-5 catalyst with different Si/A12 ratios was studied. The effect of acid density of catalyst on the oligomerization of ethylene was discussed. By increasing the acid density of catalyst, ethylene conversion showed a linear increase, while the yields of olefins decreased when the acid density of catalyst exceeded 0.14mmolNH3/g owing to a promotion of hydrogen transfer reaction. Through comparing the average distance between acid sites on catalyst with kinetic diameters of olefins, it was found that the dimerization of ethylene was not restrained by the sparse distribution of acid sites, while the hydrogen transfer reaction of C3 and C4 olefins was limited. On these bases, a conclusion is proposed that the dimerization of ethylene proceeded via Eley-Rideal mechanism, while the hydrogen transfer reaction of C3 and C4 olefins followed the Langmuir-Hinshelwood mechanism.展开更多
AIM:To evaluate the potential efficacy and mechanisms of nintedanib in corneal neovascularization(NV)in rabbit models.METHODS:Corneal NV was induced using 1 mol/L Na OH.Rabbits(n=21)were randomized to 3 groups:Group 1...AIM:To evaluate the potential efficacy and mechanisms of nintedanib in corneal neovascularization(NV)in rabbit models.METHODS:Corneal NV was induced using 1 mol/L Na OH.Rabbits(n=21)were randomized to 3 groups:Group 1 were treated with 0.9%NaCl,Group 2 with Avastin(5 mg/mL),and Group 3 with nintedanib(1 mg/mL).All treatments star ted 1 d af ter alkaline burns and were topically performed 3 times a day for 2 wk.Photographs were taken on a slit lamp microscope on day 7 and 14.The NV area,the length of the vascularization and angiogenesis index(AI)were used to evaluate the corneal NV.On day 14,the immunohistochemical(IHC)studies of the cornea were examined.Western blot was performed to test the expression levels of vascular endothelial growth factor(VEGF),Akt,p-Akt,P38,p-P38,MMP-2 and MMP-9.RESULTS:The corneal NV area,vessel length and AI in Group 3 were significantly lower than Group 2,with both being lower than Group 1.IHC staining showed that VEGF was significantly overexpressed in the epithelium and stroma of cornea following alkaline burns.In contrast,the level of VEGF was significantly suppressed in both Group 2 and Group 3.Western blot results further confirmed that,compared with Group 1,Group 3 had significantly reduced expressions of VEGF,Akt,p-Akt,p-P38,MMP-2,and MMP-9 in corneal tissues.Trends of lower levels of MMP-2,AKT,and p-AKT in Group 3 than Group 2 were identified.CONCLUSION:Nintedanib and Avastin can effectively inhibit corneal NV,with P38 MAPK and AKT signaling pathways being possibly involved.Nintedanib seems more effective than Avastin and has the potential to be a novel therapy for preventing corneal NV.展开更多
Natural radioactivity is very important for the assessment of the marine sand property and usability. By using gamma spectrometry, the concentration of the natural radionuclides 226Ra, 232Th and 40K have been measured...Natural radioactivity is very important for the assessment of the marine sand property and usability. By using gamma spectrometry, the concentration of the natural radionuclides 226Ra, 232Th and 40K have been measured in marine sand deposits from Liaodong Bay (LDB), North Yellow Sea (NYS), Zhoushan area (ZS), Taiwan Shoal (TS) and Pearl River Mouth (PR), offshore China, which are potential marine sand mining areas. The radiation activity equivalent (Raeq), indoor gamma absorbed dose rate (DR), annual effective dose (HR), alpha index (Ia), gamma index (Ig), external radiation hazard index (Hex), internal radiation hazard index (Hin), representative level index (RLI), excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent (AGDE) associated with the natural radionuclides are calculated to assess the radiation hazard of the natural radioactivity in the marine sands offshore China. From the analysis, it is found that these marine sands are safe for the constructions. The Pearson correlation coefficient reveals that the 226Ra distribution in the marine sands offshore China is controlled by the variation of the 40K concentration. Principal component analysis (PCA) yields a two-component representation of the entire data from the marine sands, wherein 98.22% of the total variance is explained. Our results provide good baseline data to expand the database of radioactivity of building materials in China and all over the world.展开更多
Drought is one of the major meteorological disasters affecting the climate in China.In this paper,the interannual variation and seasonal distribution changes of drought at different time scales were analyzed with the ...Drought is one of the major meteorological disasters affecting the climate in China.In this paper,the interannual variation and seasonal distribution changes of drought at different time scales were analyzed with the standardized precipitation index( SPI) as the drought evaluation criterion to the precipitation data of the 5 meteorological stations of Jinan,Tai'an,Yiyuan,Shen County and Yanzhou from 1960 to 2013.The results showed that:(1) the frequency of drought was low in spring and summer in inland areas of Shandong Province,while autumn had frequent occurrences of moderate drought,and winter had frequent occurrences of heavy and severe droughts.(2) In the 1960 s,1980 s and early 21^(st) century,the number of droughts increased significantly,and the SPI values showed a significant decrease.(3) The 3-month time scale range was wide,during which the frequency of occurrence was high.The trend of SPI changes at the 12-month time scale was affected by the accumulation of antecedent precipitation,and the change was slow.The research results can provide a scientific reference for arid climate analysis and water resources management in agriculture and production in inland areas of Shandong Province.展开更多
Air pollution has become the most concerned regional environmental problem in China at present.According to the data of typical cities in Shandong Province from January,2014 to December,2015,the air quality status,pol...Air pollution has become the most concerned regional environmental problem in China at present.According to the data of typical cities in Shandong Province from January,2014 to December,2015,the air quality status,pollution status and spatial variation characteristics of air pollutants were classified and analyzed,thereby providing a scientific basis for air pollution control.The conclusions of this study are as follows:(1) PM_(2.5) was the most important atmospheric pollutant in Shandong Province;(2) Qingdao had the best air quality with a good air quality rate of 73.7%,while Jinan had the worst air quality with a good air quality rate only of 31.3%; and(3) the days with heavy pollution were mainly concentrated in winter,mainly due to coal-fired heating in winter.展开更多
Electrochemical CO_(2)reduction has the vast potential to neutralize CO_(2)emission and valorizes this greenhouse gas into chemicals and fuels under mild conditions.Its commercial realization hinges on catalyst innova...Electrochemical CO_(2)reduction has the vast potential to neutralize CO_(2)emission and valorizes this greenhouse gas into chemicals and fuels under mild conditions.Its commercial realization hinges on catalyst innovation as well as device engineering for enabling reactions at industrially relevant conditions.Copper has been widely examined for the selective production of multicarbon chemicals particularly ethylene,while there is still a substantial gap between the expected and the attainable.In this work,we report that the surface promotion of copper with alumina clusters is a viable strategy to enhance its electrocatalytic performance.AlOx-promoted Cu catalyst is derived from Cu-Al layered double hydroxide nanosheets after alkali etching and cathodic conversion.It can catalyze CO_(2)to ethylene and multicarbon products with great selectivity and stability far superior to pristine copper in both an H-cell and a zero-gap membrane electrode assembly(MEA)electrolyzer.The surface promotion effect is understood via computational simulations showing that alumina clusters can stabilize key reaction intermediates(*COOH and*OCCOH)along the reaction pathway.展开更多
Auditory neuropathy spectrum disorder(ANSD)represents a variety of sensorineural deafness conditions characterized by abnormal inner hair cells and/or auditory nerve function,but with the preservation of outer hair ce...Auditory neuropathy spectrum disorder(ANSD)represents a variety of sensorineural deafness conditions characterized by abnormal inner hair cells and/or auditory nerve function,but with the preservation of outer hair cell function.ANSD represents up to 15%of individuals with hearing impairments.Through mutation screening,bioinformatic analysis and expression studies,we have previously identified several apoptosis-inducing factor(AIF)mitochondria-associated 1(AIFM1)variants in ANSD families and in some other sporadic cases.Here,to elucidate the pathogenic mechanisms underlying each AIFM1 variant,we generated AIF-null cells using the clustered regularly interspersed short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)system and constructed AIF-wild type(WT)and AIF-mutant(mut)(p.T260A,p.R422W,and p.R451Q)stable transfection cell lines.We then analyzed AIF structure,coenzyme-binding affinity,apoptosis,and other aspects.Results revealed that these variants resulted in impaired dimerization,compromising AIF function.The reduction reaction of AIF variants had proceeded slower than that of AIF-WT.The average levels of AIF dimerization in AIF variant cells were only 34.5%-49.7%of that of AIF-WT cells,resulting in caspase-independent apoptosis.The average percentage of apoptotic cells in the variants was 12.3%-17.9%,which was significantly higher than that(6.9%-7.4%)in controls.However,nicotinamide adenine dinucleotide(NADH)treatment promoted the reduction of apoptosis by rescuing AIF dimerization in AIF variant cells.Our findings show that the impairment of AIF dimerization by AIFM1 variants causes apoptosis contributing to ANSD,and introduce NADH as a potential drug for ANSD treatment.Our results help elucidate the mechanisms of ANSD and may lead to the provision of novel therapies.展开更多
The CO electroreduction reaction(CORR)represents an important piece of the decarbonization puzzle and is heavily inspired by research on the CO_(2) electroreduction reaction(CO_(2)RR).Compared to its parent reaction,C...The CO electroreduction reaction(CORR)represents an important piece of the decarbonization puzzle and is heavily inspired by research on the CO_(2) electroreduction reaction(CO_(2)RR).Compared to its parent reaction,CORR circumvents the(bi)carbonate issue that plagues CO_(2)RR,potentially enabling greater stability and selectivity toward C2þproducts,particularly oxygenates.Despite its unique potential,CORR still suffers from unsatisfactory performance.In this perspective article,we aim to provide a concise and informative overview of CORR and its close connection with CO_(2)RR.We start by briefly presenting the two reactions’similarities and differences,then discussing several catalyst design strategies.This is followed by highlights of the latest results on device integration and engineering.Finally,we offer our thoughts about possible future research opportunities that could render this technology a practical reality.展开更多
This study was to determine the fermentation quality of a mixture of corn steep liquor(CSL)(178 g/kg wet basis) and air-dried rice straw(356 g/kg wet basis) after being treated with inoculants of different types of la...This study was to determine the fermentation quality of a mixture of corn steep liquor(CSL)(178 g/kg wet basis) and air-dried rice straw(356 g/kg wet basis) after being treated with inoculants of different types of lactic acid bacteria(LAB). The treatments included the addition of no LAB additive(control),which was deionized water; homo-fermentative LAB alone(^(ho)LAB), which was Lactobacillus plantarum alone), and a mixture of homo-fermentative and hetero-fermentative LAB(^(he+ho)LAB), which were L. plantarum, Lactobacillus casei, and Lactobacillus buchneri. The results showed that the inoculation of the mixture of CSL and air-dried rice straw with ^(he+ho)LAB significantly increased the concentration of acetic acid and lactic acid compared with the control(P < 0.05). The addition of ^(he+ho)LAB effectively inhibited the growth of yeast in the silage. The concentration of total lactic acid bacteria in the ^(he+ho)LAB-treated silage was significant higher than those obtained in other groups(P < 0.05). The duration of the aerobic stability of the silages increased from 56 h to >372 h. The control group was the first to spoil, whereas the silage treated with ^(he+ho)LAB remained stable throughout the 372 h period of monitoring. The results demonstrated that the ^(he+ho)LAB could effectively improve the fermentation quality and aerobic stability of the silage.展开更多
Desertification is a severe environmental problem induced by both climate change and human activities.This study assessed the relative contribution of climate change,human activities,and different climatic and anthrop...Desertification is a severe environmental problem induced by both climate change and human activities.This study assessed the relative contribution of climate change,human activities,and different climatic and anthropogenic factors in desertification reversion and expansion of North China from 1981 to 2010.The results showed that the desertification of North China had changed significantly over the past 30 years;desertification reversion and expansion covered an area of 750,464 km^2, and the spatial distribution of these regions exhibited considerable heterogeneity.For desertification reversion, climate change and human activity accounted for 22.6% and 26%,respectively of total reverted land.Wind speed reduction and the improvement ofhydrothermal conditions were the most important climatic factors for desertification reversion in the arid region of Northwest China (ARNC) and the Three-River Headwaters region (TRHR),and the reduction in grassland use intensity was the most important anthropogenic factor related to desertification reversion in Inner Mongolia and regions along the Great Wall (IMGW). For desertification expansion,the relative role of climate change was more obvious,which was mainly attributed to the continuous reduction in precipitation in eastern IMGW, and the increase in grassland use intensity was the main factor underlying regional human-induced desertification expansion.展开更多
Purpose–Basic safety message(BSM)is a core subset of standard protocols for connected vehicle system to transmit related safety information via vehicle-to-vehicle(V2V)and vehicle-to-infrastructure(V2I).Although some ...Purpose–Basic safety message(BSM)is a core subset of standard protocols for connected vehicle system to transmit related safety information via vehicle-to-vehicle(V2V)and vehicle-to-infrastructure(V2I).Although some safety prototypes of connected vehicle have been proposed with effective strategies,few of them are fully evaluated in terms of the significance of BSM messages on performance of safety applications when in emergency.Design/methodology/approach–To address this problem,a data fusion method is proposed to capture the vehicle crash risk by extracting critical information from raw BSMs data,such as driver volition,vehicle speed,hard accelerations and braking.Thereafter,a classification model based on information-entropy and variable precision rough set(VPRS)is used for assessing the instantaneous driving safety by fusing the BSMs data fromfield test,and predicting the vehicle crash risk level with the driver emergency maneuvers in the next short term.Findings–Thefindings and implications are discussed for developing an improved warning and driving assistant system by using BSMs messages.Originality/value–Thefindings of this study are relevant to incorporation of alerts,warnings and control assists in V2V applications of connected vehicles.Such applications can help drivers identify situations where surrounding drivers are volatile,and they may avoid dangers by taking defensive actions.展开更多
文摘FCC dry gas contains a large amount of ethylene. It is used by most of the refineries in China as fuel or simply burned in atmosphere. Few refineries make good use of the dry gas, so the precious ethylene resource in the dry gas is wasted. In this article, the possibility of catalytic conversion of ethylene to C3, C4, and some high molecular weight hydrocarbons in a fixed bed micro-reactor using LTB-1 catalyst, with pure ethylene as feedstock was studied. Effects of reaction temperature, reaction pressure, and feedstock flow rate, on the conversion of ethylene and the distribution of products were investigated to determine the proper reaction parameters to be used in practice. Good results indicate that this study may provide a new way of using the ethylene resource in the FCC dry gas.
文摘The oligomerization of ethylene in FCC dry gas over HZSM-5 catalyst with different Si/A12 ratios was studied. The effect of acid density of catalyst on the oligomerization of ethylene was discussed. By increasing the acid density of catalyst, ethylene conversion showed a linear increase, while the yields of olefins decreased when the acid density of catalyst exceeded 0.14mmolNH3/g owing to a promotion of hydrogen transfer reaction. Through comparing the average distance between acid sites on catalyst with kinetic diameters of olefins, it was found that the dimerization of ethylene was not restrained by the sparse distribution of acid sites, while the hydrogen transfer reaction of C3 and C4 olefins was limited. On these bases, a conclusion is proposed that the dimerization of ethylene proceeded via Eley-Rideal mechanism, while the hydrogen transfer reaction of C3 and C4 olefins followed the Langmuir-Hinshelwood mechanism.
基金Supported by the Natural Science Foundation of Tianjin City(No.2150000045)。
文摘AIM:To evaluate the potential efficacy and mechanisms of nintedanib in corneal neovascularization(NV)in rabbit models.METHODS:Corneal NV was induced using 1 mol/L Na OH.Rabbits(n=21)were randomized to 3 groups:Group 1 were treated with 0.9%NaCl,Group 2 with Avastin(5 mg/mL),and Group 3 with nintedanib(1 mg/mL).All treatments star ted 1 d af ter alkaline burns and were topically performed 3 times a day for 2 wk.Photographs were taken on a slit lamp microscope on day 7 and 14.The NV area,the length of the vascularization and angiogenesis index(AI)were used to evaluate the corneal NV.On day 14,the immunohistochemical(IHC)studies of the cornea were examined.Western blot was performed to test the expression levels of vascular endothelial growth factor(VEGF),Akt,p-Akt,P38,p-P38,MMP-2 and MMP-9.RESULTS:The corneal NV area,vessel length and AI in Group 3 were significantly lower than Group 2,with both being lower than Group 1.IHC staining showed that VEGF was significantly overexpressed in the epithelium and stroma of cornea following alkaline burns.In contrast,the level of VEGF was significantly suppressed in both Group 2 and Group 3.Western blot results further confirmed that,compared with Group 1,Group 3 had significantly reduced expressions of VEGF,Akt,p-Akt,p-P38,MMP-2,and MMP-9 in corneal tissues.Trends of lower levels of MMP-2,AKT,and p-AKT in Group 3 than Group 2 were identified.CONCLUSION:Nintedanib and Avastin can effectively inhibit corneal NV,with P38 MAPK and AKT signaling pathways being possibly involved.Nintedanib seems more effective than Avastin and has the potential to be a novel therapy for preventing corneal NV.
文摘Natural radioactivity is very important for the assessment of the marine sand property and usability. By using gamma spectrometry, the concentration of the natural radionuclides 226Ra, 232Th and 40K have been measured in marine sand deposits from Liaodong Bay (LDB), North Yellow Sea (NYS), Zhoushan area (ZS), Taiwan Shoal (TS) and Pearl River Mouth (PR), offshore China, which are potential marine sand mining areas. The radiation activity equivalent (Raeq), indoor gamma absorbed dose rate (DR), annual effective dose (HR), alpha index (Ia), gamma index (Ig), external radiation hazard index (Hex), internal radiation hazard index (Hin), representative level index (RLI), excess lifetime cancer risk (ELCR) and annual gonadal dose equivalent (AGDE) associated with the natural radionuclides are calculated to assess the radiation hazard of the natural radioactivity in the marine sands offshore China. From the analysis, it is found that these marine sands are safe for the constructions. The Pearson correlation coefficient reveals that the 226Ra distribution in the marine sands offshore China is controlled by the variation of the 40K concentration. Principal component analysis (PCA) yields a two-component representation of the entire data from the marine sands, wherein 98.22% of the total variance is explained. Our results provide good baseline data to expand the database of radioactivity of building materials in China and all over the world.
基金Supported by Colleges and universities scientific research project of Shandong(J18KA197)
文摘Drought is one of the major meteorological disasters affecting the climate in China.In this paper,the interannual variation and seasonal distribution changes of drought at different time scales were analyzed with the standardized precipitation index( SPI) as the drought evaluation criterion to the precipitation data of the 5 meteorological stations of Jinan,Tai'an,Yiyuan,Shen County and Yanzhou from 1960 to 2013.The results showed that:(1) the frequency of drought was low in spring and summer in inland areas of Shandong Province,while autumn had frequent occurrences of moderate drought,and winter had frequent occurrences of heavy and severe droughts.(2) In the 1960 s,1980 s and early 21^(st) century,the number of droughts increased significantly,and the SPI values showed a significant decrease.(3) The 3-month time scale range was wide,during which the frequency of occurrence was high.The trend of SPI changes at the 12-month time scale was affected by the accumulation of antecedent precipitation,and the change was slow.The research results can provide a scientific reference for arid climate analysis and water resources management in agriculture and production in inland areas of Shandong Province.
基金Supported by Colleges and universities scientific research project of Shandong(J18KA197)
文摘Air pollution has become the most concerned regional environmental problem in China at present.According to the data of typical cities in Shandong Province from January,2014 to December,2015,the air quality status,pollution status and spatial variation characteristics of air pollutants were classified and analyzed,thereby providing a scientific basis for air pollution control.The conclusions of this study are as follows:(1) PM_(2.5) was the most important atmospheric pollutant in Shandong Province;(2) Qingdao had the best air quality with a good air quality rate of 73.7%,while Jinan had the worst air quality with a good air quality rate only of 31.3%; and(3) the days with heavy pollution were mainly concentrated in winter,mainly due to coal-fired heating in winter.
基金the financial support from the National Natural Science Foundation of China(Nos.U2002213 and 52161160331)the Science and Technology Development Fund Macao SAR(No.0077/2021/A2)the Collaborative Innovation Center of Suzhou Nano Science and Technology,the 111 Project and Joint International Research Laboratory of Carbon-Based Functional Materials and Devices.
文摘Electrochemical CO_(2)reduction has the vast potential to neutralize CO_(2)emission and valorizes this greenhouse gas into chemicals and fuels under mild conditions.Its commercial realization hinges on catalyst innovation as well as device engineering for enabling reactions at industrially relevant conditions.Copper has been widely examined for the selective production of multicarbon chemicals particularly ethylene,while there is still a substantial gap between the expected and the attainable.In this work,we report that the surface promotion of copper with alumina clusters is a viable strategy to enhance its electrocatalytic performance.AlOx-promoted Cu catalyst is derived from Cu-Al layered double hydroxide nanosheets after alkali etching and cathodic conversion.It can catalyze CO_(2)to ethylene and multicarbon products with great selectivity and stability far superior to pristine copper in both an H-cell and a zero-gap membrane electrode assembly(MEA)electrolyzer.The surface promotion effect is understood via computational simulations showing that alumina clusters can stabilize key reaction intermediates(*COOH and*OCCOH)along the reaction pathway.
基金the National Natural Science Foundation of China(Nos.32070584,81830028,31771398,82222016,and 8207040100)the Zhejiang Provincial Natural Science Foundation of China(No.LZ19C060001)the Fundamental Research Funds for the Central Universities(No.2019QNA6001)。
文摘Auditory neuropathy spectrum disorder(ANSD)represents a variety of sensorineural deafness conditions characterized by abnormal inner hair cells and/or auditory nerve function,but with the preservation of outer hair cell function.ANSD represents up to 15%of individuals with hearing impairments.Through mutation screening,bioinformatic analysis and expression studies,we have previously identified several apoptosis-inducing factor(AIF)mitochondria-associated 1(AIFM1)variants in ANSD families and in some other sporadic cases.Here,to elucidate the pathogenic mechanisms underlying each AIFM1 variant,we generated AIF-null cells using the clustered regularly interspersed short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)system and constructed AIF-wild type(WT)and AIF-mutant(mut)(p.T260A,p.R422W,and p.R451Q)stable transfection cell lines.We then analyzed AIF structure,coenzyme-binding affinity,apoptosis,and other aspects.Results revealed that these variants resulted in impaired dimerization,compromising AIF function.The reduction reaction of AIF variants had proceeded slower than that of AIF-WT.The average levels of AIF dimerization in AIF variant cells were only 34.5%-49.7%of that of AIF-WT cells,resulting in caspase-independent apoptosis.The average percentage of apoptotic cells in the variants was 12.3%-17.9%,which was significantly higher than that(6.9%-7.4%)in controls.However,nicotinamide adenine dinucleotide(NADH)treatment promoted the reduction of apoptosis by rescuing AIF dimerization in AIF variant cells.Our findings show that the impairment of AIF dimerization by AIFM1 variants causes apoptosis contributing to ANSD,and introduce NADH as a potential drug for ANSD treatment.Our results help elucidate the mechanisms of ANSD and may lead to the provision of novel therapies.
基金support from the National Natural Science Foundation of China (U2002213 and 52161160331)the Science and Technology Development Fund Macao SAR (0077/2021/A2)+1 种基金the Natural Science Foundation of Jiangsu Province of China (BK20220027)the Collaborative Innovation Center of Suzhou Nano Science and Technology,the 111 Project and Joint International Research Laboratory of Carbon-Based Functional Materials and Devices.
文摘The CO electroreduction reaction(CORR)represents an important piece of the decarbonization puzzle and is heavily inspired by research on the CO_(2) electroreduction reaction(CO_(2)RR).Compared to its parent reaction,CORR circumvents the(bi)carbonate issue that plagues CO_(2)RR,potentially enabling greater stability and selectivity toward C2þproducts,particularly oxygenates.Despite its unique potential,CORR still suffers from unsatisfactory performance.In this perspective article,we aim to provide a concise and informative overview of CORR and its close connection with CO_(2)RR.We start by briefly presenting the two reactions’similarities and differences,then discussing several catalyst design strategies.This is followed by highlights of the latest results on device integration and engineering.Finally,we offer our thoughts about possible future research opportunities that could render this technology a practical reality.
基金financially supported by the National Dairy Industry and Technology System project (CARS-37)of Agriculture Ministry in China
文摘This study was to determine the fermentation quality of a mixture of corn steep liquor(CSL)(178 g/kg wet basis) and air-dried rice straw(356 g/kg wet basis) after being treated with inoculants of different types of lactic acid bacteria(LAB). The treatments included the addition of no LAB additive(control),which was deionized water; homo-fermentative LAB alone(^(ho)LAB), which was Lactobacillus plantarum alone), and a mixture of homo-fermentative and hetero-fermentative LAB(^(he+ho)LAB), which were L. plantarum, Lactobacillus casei, and Lactobacillus buchneri. The results showed that the inoculation of the mixture of CSL and air-dried rice straw with ^(he+ho)LAB significantly increased the concentration of acetic acid and lactic acid compared with the control(P < 0.05). The addition of ^(he+ho)LAB effectively inhibited the growth of yeast in the silage. The concentration of total lactic acid bacteria in the ^(he+ho)LAB-treated silage was significant higher than those obtained in other groups(P < 0.05). The duration of the aerobic stability of the silages increased from 56 h to >372 h. The control group was the first to spoil, whereas the silage treated with ^(he+ho)LAB remained stable throughout the 372 h period of monitoring. The results demonstrated that the ^(he+ho)LAB could effectively improve the fermentation quality and aerobic stability of the silage.
基金This research was jointly supported by the National Key Research and Development Program of China (No.2016YFC0501002)the National Natural Science Foundation of China (Grant No.71573245).
文摘Desertification is a severe environmental problem induced by both climate change and human activities.This study assessed the relative contribution of climate change,human activities,and different climatic and anthropogenic factors in desertification reversion and expansion of North China from 1981 to 2010.The results showed that the desertification of North China had changed significantly over the past 30 years;desertification reversion and expansion covered an area of 750,464 km^2, and the spatial distribution of these regions exhibited considerable heterogeneity.For desertification reversion, climate change and human activity accounted for 22.6% and 26%,respectively of total reverted land.Wind speed reduction and the improvement ofhydrothermal conditions were the most important climatic factors for desertification reversion in the arid region of Northwest China (ARNC) and the Three-River Headwaters region (TRHR),and the reduction in grassland use intensity was the most important anthropogenic factor related to desertification reversion in Inner Mongolia and regions along the Great Wall (IMGW). For desertification expansion,the relative role of climate change was more obvious,which was mainly attributed to the continuous reduction in precipitation in eastern IMGW, and the increase in grassland use intensity was the main factor underlying regional human-induced desertification expansion.
基金supported by National Key R&D Program of China(Grant No.2017YFC0803900)National Nature Science Foundation of China(Grant No.61703160,No.51775396)+1 种基金Jiangxi Provincial Department of Education Science Research Fund Project(No.GJJ170420)Jiangxi Provincial Department of Transportation Science Research Fund Project(No.2018X0015).
文摘Purpose–Basic safety message(BSM)is a core subset of standard protocols for connected vehicle system to transmit related safety information via vehicle-to-vehicle(V2V)and vehicle-to-infrastructure(V2I).Although some safety prototypes of connected vehicle have been proposed with effective strategies,few of them are fully evaluated in terms of the significance of BSM messages on performance of safety applications when in emergency.Design/methodology/approach–To address this problem,a data fusion method is proposed to capture the vehicle crash risk by extracting critical information from raw BSMs data,such as driver volition,vehicle speed,hard accelerations and braking.Thereafter,a classification model based on information-entropy and variable precision rough set(VPRS)is used for assessing the instantaneous driving safety by fusing the BSMs data fromfield test,and predicting the vehicle crash risk level with the driver emergency maneuvers in the next short term.Findings–Thefindings and implications are discussed for developing an improved warning and driving assistant system by using BSMs messages.Originality/value–Thefindings of this study are relevant to incorporation of alerts,warnings and control assists in V2V applications of connected vehicles.Such applications can help drivers identify situations where surrounding drivers are volatile,and they may avoid dangers by taking defensive actions.