A comprehensive examination of detrital sandstone modes from the Sylhet Trough reveals a diverse range of sub-lithic to sub-feldspathic quartz arenites.Soil samples were gathered from Dupi Gaon(Jaintiapur)in Banglades...A comprehensive examination of detrital sandstone modes from the Sylhet Trough reveals a diverse range of sub-lithic to sub-feldspathic quartz arenites.Soil samples were gathered from Dupi Gaon(Jaintiapur)in Bangladesh,followed by a thorough analysis using field examination,X-ray diffraction(XRD),X-ray fluorescence(XRF),petrography,and heavy mineral concentration analyses.Field observations revealed the soil sample varying from white to yellowish to variegated,with thicknesses ranging from 15 cm to about 4 m,and exhibiting moderate softness.XRF analysis revealed significant SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)levels in the samples,with zirconium(Zr)and copper(Cu)showing consistently high concentrations.XRD analysis identified quartz as predominant,along with muscovite,biotite,and accessory minerals like rutile and magnetite.Petrographic analysis highlighted quartz as dominant,with fractures suggesting tectonic influences,while heavy mineral separation techniques identified zircon,garnet,goethite,rutile,and magnetite.These findings provide insights into sediment provenance,depositional processes,and environ-mental conditions during the formation of the Dupi Tila Formation.The comprehensive geochemical data of the entire rock indicates that most of the sediments originated from felsic igneous sources,and also suggests a moderate to high level of weathering in the source region.Overall,the analyses suggested an in situ origin of the Dupi Tila Formation,with parent materials being predominantly detrital rather than authigenic,supported by the presence of detrital quartz and an assessment of the depositional environment,providing insights into the geological conditions of the era and potential modes of sediment transportation.展开更多
Electrocatalytic reduction of nitrate pollutants to produce ammonia offers an effective approach to realizing the artificial nitrogen cycle and replacing the energyintensive Haber-Bosch process.Nitrite is an important...Electrocatalytic reduction of nitrate pollutants to produce ammonia offers an effective approach to realizing the artificial nitrogen cycle and replacing the energyintensive Haber-Bosch process.Nitrite is an important intermediate product in the reduction of nitrate to ammonia.Therefore,the mechanism of converting nitrite into ammonia warrants further investigation.Molecular cobalt catalysts are regarded as promising for nitrite reduction reactions(NO_(2)^(−)RR).However,designing and controlling the coordination environment of molecular catalysts is crucial for studying the mechanism of NO_(2)^(−)RR and catalyst design.Herein,we develop a molecular platform of cobalt porphyrin with three coordination microenvironments(Co-N_(3)X_(1),X=N,O,S).Electrochemical experiments demonstrate that cobalt porphyrin with O coordination(CoOTPP)exhibits the lowest onset potential and the highest activity for NO_(2)^(−)RR in ammonia production.Under neutral,nonbuffered conditions over a wide potential range(−1.0 to−1.5 V versus AgCl/Ag),the Faradaic efficiency of nearly 90%for ammonia was achieved and reached 94.5%at−1.4 V versus AgCl/Ag,with an ammonia yield of 6,498μgh^(−1)and a turnover number of 22,869 at−1.5V versus AgCl/Ag.In situ characterization and density functional theory calculations reveal that modulating the coordination environment alters the electron transfer mode of the cobalt active center and the charge redistribution caused by the break of the ligand field.Therefore,this results in enhanced electrochemical activity for NO_(2)^(−)RR in ammonia production.This study provides valuable guidance for designing adjustments to the coordination environment of molecular catalysts to enhance catalytic activity.展开更多
For internal combustion engines,engines installed for transport ships,cargo ships,and fishing vessels are mainly diesel engines.The number of engines is increasing due to the development of the maritime and seafood ex...For internal combustion engines,engines installed for transport ships,cargo ships,and fishing vessels are mainly diesel engines.The number of engines is increasing due to the development of the maritime and seafood exploitation sectors.Therefore,the high demand for petroleum fuels increases environmental pollution due to engine emissions.Reducing environmental pollution from the combustion of petroleum fuels has become a concern worldwide,especially for internal combustion engines.The exhaust gases from the engine contain harmful substances such as soot and nitrogen oxides(NO_(x)).Fuels with higher carbon content generate more soot when burned.In contrast,biofuels have low carbon and sulfur content and supply ample oxygen,which helps to reduce soot formation.For these reasons,biofuels are encouraged as alternative fuels to petroleum.Vegetable oil is one of the primary raw materials for biofuel production.This study presents a mixture of diesel and vegetable oil utilized as fuel for fishing vessels’diesel engines.The results of experimental research on a fishing vessel’s 4CHE Yanmar diesel engine when using diesel fuel mixed with coconut oil(B15,15%coconut oil,and 85%diesel)show that increasing B15 fuel injection pressure by about 10–15%compared with diesel fuel injection pressure reduces the engine’s soot emissions and increases power compared to unadjusted.This solution contributes to reducing environmental pollution from engine emissions.展开更多
Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems.However,the distribution of microbial functional genes and th...Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems.However,the distribution of microbial functional genes and their influencing factors in hot springs remain largely unclear.Therefore,this study investigated the microbial functional genes and their potential for controlling biogeochemical cycles(C,N,S,and P) in the hot Springs of Tengchong,China,using the Geochip method,a functional gene microarray technology.The examined hot springs have very different microbial functional genes.A total of 22 736 gene probe signals were identified,belonging to 567 functional genes and associated with 15 ecological functions,mainly involving stress response,carbon cycle,nitrogen cycle,sulfur cycle,phosphorus cycle and energy processes.The amyA,narG,dsrA and ppx genes were most abundant in carbon,nitrogen,sulfur and phosphorus cycles,respectively,and were significantly correlated with pH,temperature and SO_(4)^(2-).The diversity and abundance of detected gene probes were negatively correlated with temperature.The α-diversity(i.e.,Shannon index) was high at low temperature and low pH.Molecular functional interactions revealed by the gene connectivity levels were negatively correlated with temperature,pH and SO_(4)^(2-).These results suggested that the abundance,diversity and interactions of microbial functional genes were significantly influenced by geochemical parameters.-In addition,some genera possessed functional genes related to carbon,nitrogen,sulfur,and phosphorus cycles and can synergistically control the biogeochemical cycles of carbon,nitrogen,sulfur and phosphorus.These findings provide new insights into the functional potentials of microorganisms to participate in biogeochemical cycles and their responses to environmental factors in hot springs.展开更多
This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China ...This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China Family Panel Studies(CFPS)data,1491 children(girls ratio=53.78%;average grade=6.023 years,school grade standard deviation=1.825 years).Results following multiple regression model(OLS)show that the higher the parental cognitive ability,the higher the children’s logical reasoning ability.Secondly,parental academic expectation serves as a mediator between their cognitive ability and children’s logical reasoning ability for higher logical reasoning by children.Third,a possible family environment acts as a mediator in the relationship between parents’cognitive ability and children’s logical reasoning ability to be higher.We conclude from thesefindings that parents with high cognitive abilities can enhance their children’s logical reasoning skills not only by setting higher academic expectations,but also by cultivating a supportive family environment.Thesefindings imply a need for intervention to improve family quality of life to enhance children’s thinking abilities to optimize their academic learning.展开更多
With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comp...With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comprise heterogeneous networks where outdated systems coexist with the latest devices,spanning a range of devices from non-encrypted ones to fully encrypted ones.Given the limited visibility into payloads in this context,this study investigates AI-based attack detection methods that leverage encrypted traffic metadata,eliminating the need for decryption and minimizing system performance degradation—especially in light of these heterogeneous devices.Using the UNSW-NB15 and CICIoT-2023 dataset,encrypted and unencrypted traffic were categorized according to security protocol,and AI-based intrusion detection experiments were conducted for each traffic type based on metadata.To mitigate the problem of class imbalance,eight different data sampling techniques were applied.The effectiveness of these sampling techniques was then comparatively analyzed using two ensemble models and three Deep Learning(DL)models from various perspectives.The experimental results confirmed that metadata-based attack detection is feasible using only encrypted traffic.In the UNSW-NB15 dataset,the f1-score of encrypted traffic was approximately 0.98,which is 4.3%higher than that of unencrypted traffic(approximately 0.94).In addition,analysis of the encrypted traffic in the CICIoT-2023 dataset using the same method showed a significantly lower f1-score of roughly 0.43,indicating that the quality of the dataset and the preprocessing approach have a substantial impact on detection performance.Furthermore,when data sampling techniques were applied to encrypted traffic,the recall in the UNSWNB15(Encrypted)dataset improved by up to 23.0%,and in the CICIoT-2023(Encrypted)dataset by 20.26%,showing a similar level of improvement.Notably,in CICIoT-2023,f1-score and Receiver Operation Characteristic-Area Under the Curve(ROC-AUC)increased by 59.0%and 55.94%,respectively.These results suggest that data sampling can have a positive effect even in encrypted environments.However,the extent of the improvement may vary depending on data quality,model architecture,and sampling strategy.展开更多
With the rapid development of economy, requirements on indoor environment design are getting higher and higher, but its prosperity brings ecological environment serious destruction and over consumption of resources. U...With the rapid development of economy, requirements on indoor environment design are getting higher and higher, but its prosperity brings ecological environment serious destruction and over consumption of resources. Under the global environment of the sustainable development, the principles of indoor environment design were analyzed ecologically and corresponding implementation methods were proposed to provide reference for energy-conservation and gas emission-reduction in the ecological system of indoor environment.展开更多
Colorectal cancer(CRC)is one of the leading causes of cancer and cancer-related mortality worldwide.The disease has been traditionally a major health problem in industrial countries,however the CRC rates are increasin...Colorectal cancer(CRC)is one of the leading causes of cancer and cancer-related mortality worldwide.The disease has been traditionally a major health problem in industrial countries,however the CRC rates are increasing in the developing countries that are undergoing economic growth.Several environmental risk factors,mainly changes in diet and life style,have been suggested to underlie the rise of CRC in these populations.Diet and lifestyle impinge on nuclear receptors,on the intestinal microbiota and on crucial molecular pathways that are implicated in intestinal carcinogenesis.In this respect,the epidemiological transition in several regions of the world offers a unique opportunity to better understand CRC carcinogenesis by studying the disease phenotypes and their environmental and molecular associations in different populations.The data from these studies may have important implications for the global prevention and treatment of CRC.展开更多
The purpose of this study was to evaluate the roles of different housing environments in neurological function, cerebral metabolism, cerebral infarction and neuron apoptosis after focal cerebral ischemia. Twenty-eight...The purpose of this study was to evaluate the roles of different housing environments in neurological function, cerebral metabolism, cerebral infarction and neuron apoptosis after focal cerebral ischemia. Twenty-eight Sprague-Dawley rats were divided into control group （CG） and cerebral ischemia group, and the latter was further divided into subgroups of different housing conditions： standard environment （SE） subgroup, individual living environment （IE） subgroup, and enriched environment （EE） subgroup. Focal cerebral ischemia was induced by the middle cerebral artery occlusion （MCAO）. Beam walking test was used to quantify the changes of overall motor function. Cerebral infarction and cerebral metabolism were studied by in vivo magnetic resonance imaging and 1H-magnetic resonance spectra, respectively. Neuron necrosis and apoptosis were detected by hematoxylin-eosin and TUNEL staining methods, respectively. The results showed that performance on the beam-walk test was improved in EE subgroup when compared to SE subgroup and IE subgroup. Cerebral infarct volume in IE subgroup was significantly larger than that in SE subgroup （P〈0.05） and EE subgroup （P〈0.05） on day 14 after MCAO. NAA/Cr and Cho/Cr ratios were lower in MCAO groups under different housing conditions as compared to those in CG （P〈0.05）. NAA/Cr ratio was lower in IE subgroup （P〈0.05） and higher in EE subgroup （P〈0.05） than that in SE subgroup. NAA/ Cr ratio in EE was significantly higher than that in IE subgroup （P〈0.05）. Cho/Cr ratio was decreased in MCAO groups as compared to that in CG （P〈0.05）. A significant decrease in normal neurons in cerebral cortex was observed in MCAO groups as compared to CG （P〈0.05）. The amount of normal neurons was less in IE subgroup （P〈0.05）, and more in EE subgroup （P〈0.05） than that in SE subgroup after MCAO. The amotmt of normal neurons in EE subgroup was significantly more than that in IE subgroup after MCAO （P〈0.05）. The ratio of TUNEL-positive neurons in EE was significantly lower than that in SE subgroup （P〈0.05） and IE subgroup （P〈0.05）. Correlation analysis showed that the beam walking test was negatively correlated with NAA/Cr ratio （P〈0.05）. Cerebral infarct volume was negatively correlated with both NAA/Cr ratio （P〈0.01） and Cho/Cr ratio （P〈0.01）. The amount of normal cortical neurons was positively correlated with both NAA/Cr ratio （P〈0.0I） and Cho/Cr ratio （P〈0.05）. The TUNEL-positive neurons showed a negative correlation with both NAA/Cr ratio （P〈0.01） and Cho/Cr ratio （P〈0.01）. This study goes further to show that EE may improve neurological functional deficit and cerebral metabolism, decrease cerebral infarct volume, neuron necrosis and apoptosis, while IE may aggravate brain damage after MCAO.展开更多
The first data of geochemical study of the Benevka Section cherty rocks belonging to the Taukha terrane of the Sikhote-Alin Late Jurassic-Early Cretaceous accretionary prism, Russia Far East are presented. These data ...The first data of geochemical study of the Benevka Section cherty rocks belonging to the Taukha terrane of the Sikhote-Alin Late Jurassic-Early Cretaceous accretionary prism, Russia Far East are presented. These data demonstrate essential distinctions of major, trace and rare earth element concentrations in different parts of the measured stratigraphic section. The lower chert horizons exhibit high Fe2O3 and MnO contents, low concentrations of Al2O3 and TiO2, relatively high V/Y ratio, and extremely low value of negative Ce anomaly. In contrast the upper horizons composed of clayey cherts and siliceous mudstones are characterized by high Al2O3, TiO2 and K2O contents, low Fe2O3 and MnO values, low V/Y ratio, and slightly negative Ce anomaly. In the middle part of the Benevka Section, in which cherts gradually changed to clayey cherts, intermediate geochemical characteristics are present. Based on these data obtained the depositional environments correspond to proximal to the spreding ridge, open-ocean and near continental margin regimes were successfully reconstructed from bottom to top of the Benevka Section, that indicate that significant horizontal movement took place of the sea-floor, on which the cherts were deposited.展开更多
Geochemical analysis reveals that Middle Triassic radiolarian cherts from northern Thailand,including Chiang Dao,Lamphun and Den Chai,are of biogenic origin.These cherts present slightly high SiO2 content which was po...Geochemical analysis reveals that Middle Triassic radiolarian cherts from northern Thailand,including Chiang Dao,Lamphun and Den Chai,are of biogenic origin.These cherts present slightly high SiO2 content which was possibly modified by diagenetic alteration and migration processes as indicated by negative correlation between SiO2 and most of the other major elements.The relatively high content of Cr,Zr,Hf,Rb and Th and high positive correlation of these elements with Al and Ti from the majority of cherts suggest a close relation to terrigenous component.The Ce anomaly（Ce/Ce＊） with geometric means ranging from 0.85 to 0.93 is compatible with that of continental margin composi-tion（0.67-1.52） from Murray et al.（1990） which is also consistent with low Eu anomalies（Eu/Eu＊,0.91-0.94）.Moreover,the slightly low ratios of La and Ce NASC normalized（Lan/Cen,0.91-0.94） and the low LREE and HREE ratios in most of our samples（Lan/Ybn,0.62-0.85） are in agreement with the continental margin.The result from Lan/Cen vs.Al2O3/（Al2O3＋Fe2O3） discrimination diagrams also supports the continental margin（residual basin,s.str.） interpretation.These geochemical results are compatible with geological evidence,which suggest that during the Middle Triassic,radio-larian cherts were deposited within a deeper part of a residual basin in which an accommoda-tion space was possibly controlled by faults un-der extensional regime subsequent to Late Variscan（Permian） orogeny.Paleogeographi-cally,the main Paleotethys which closed during Late Triassic should be located further to the west of these study localities.This scenario is in agreement with the current view of the Tethys in this part of the world.展开更多
In the southwestern Tianshan,the geologic ages of many strata and their depositional environments are still poorly constrained because of complex structures.The Mada＇er area is located in the Kuokesaleling belt,South...In the southwestern Tianshan,the geologic ages of many strata and their depositional environments are still poorly constrained because of complex structures.The Mada＇er area is located in the Kuokesaleling belt,Southwestern Tianshan.The cherts from the former Wupata＇erkan Group contain abundant radiolarian fossils,including 10 species which are identified as late Devonian to early Carboniferous in age.Eleven chert samples have SiO_2 contents ranging from 88.80 wt%to 93.28 wt%, and 2.02 wt%to 3.72 wt%for Al_2O_3.The SiO_2/Al_2O_3 ratios of all samples vary from 23.84 to 46.11, much lower than those of the pure cherts（80-1400）.These values suggest that the cherts contain high ratios of terrigenous materials.The Al_2O_3/（Al_2O_3＋Fe_2O_3）ratios vary between 0.64 and 0.77,whereas V and Cu concentrations range from 10.92 ppm to 26.7 ppm and from 2.15 ppm to 34.1 ppm respectively. The Ti/V ratios vary from 25.53 to 44.93.The total REE concentrations of the cherts are between 30.78 ppm and 59.26 ppm,averaging 45.46 ppm.The（La/Ce）_N ratios range from 0.81 to 1.12,and 0.88-1.33 for（La/Yb）_N,averaging 1.09,which suggests a continental margin environment.Consequently,it is inferred that the cherts formed in a residual sea environment during the late Devonian to early Carboniferous time,which suggests that the collision between the Karakum-Tarim and Kazakhstan-Junggar plates did not occur at the time.In addition,the regional geological information indicates that the study area experienced a post-collision stage during the early Permian,and thus it is likely that the collision between the two plates took place in the late Carboniferous.展开更多
By means of techniques such as inductively coupled plasma-mass spectrometry （ICP-MS） and X-ray fluorescence spectrometry （XRF）,REE geochemical characteristics and depositional environment of the black shales in Ba...By means of techniques such as inductively coupled plasma-mass spectrometry （ICP-MS） and X-ray fluorescence spectrometry （XRF）,REE geochemical characteristics and depositional environment of the black shales in Baiguoyuan Ag-V deposit,Xingshan,Hubei Province,were studied in this work. The black shales in a typical TC5 profile of Doushantuo Formation of upper Sinian period were obviously enriched in REE,especially in LREE. The REE patterns of the investigated samples normalized by Post Archean Australian Shale （PAAS） showed a flat or slight rightward inclination. The characteristic elements,their ratio and correlation diagrams showed that it should be hot-water deposit and the black shale in the study area was of a sedimentary origin. Redox sensitive metal elements pattern,trace elements index measurement in anoxic environment,Ce anomaly and δEu negative anomaly showed that the deposit environment of the black shales was a reducing and anoxic one and a slight change of the sea level could be identified. The samples relatively focused on the superimposed area of sedimentary rock and basalt in the diagram of La/Yb-ΣREE and La/Yb-Ce/La. So there might be accession of hot-water sedimentation during the period of the formation of the black rock series,mostly in normal terrigenous sedimentation with the participation of deep hot-water deposit.展开更多
: In the Hunan-Guizhou-Guangxi area there have developed very thick bedded siliceous rocks of the late Sinian. The rocks have a fairly pure composition, with an average content of siliceous minerals exceeding 95%. The...: In the Hunan-Guizhou-Guangxi area there have developed very thick bedded siliceous rocks of the late Sinian. The rocks have a fairly pure composition, with an average content of siliceous minerals exceeding 95%. They are relatively rich in Fe and Mn, and poor in Al, Ti and Mg. The Fe/Ti, (Fe+Mn)/Ti, Al/(Al+Fe+Mn) and U/Th ratios and the Al-Fe-Mn and Fe-Mn-(Ni+Co+Cu)×10 triangle diagrams all show that they are hydrothermal sedimentary siliceous rocks. In the rocks the total amount of REEs is low, the δCe shows an obvious negative anomaly and the δEu a weak anomaly, and LREE>HREE, all indicating that they are products of hydrothermal processes. The δ30Si and δ18O values, as well as the formation temperature of the rocks all clearly show that the silica forming the rocks comes from hot water. Besides, analyses of the depositional environment of the rocks using the MnO/TiO2 ratio and the δCe and δ30Si values yield the same conclusion that they are formed in environments from continental marginal slopes of a bathyal environment to oceanic basins of a deep-sea environment.展开更多
Titanium alloy Ti-Al-Nb-Zr has high specific strength and becomes a promising structural material used in the deep sea.The excellent corrosion resistance of the alloy is derived from the protective passive film formed...Titanium alloy Ti-Al-Nb-Zr has high specific strength and becomes a promising structural material used in the deep sea.The excellent corrosion resistance of the alloy is derived from the protective passive film formed on its surface.By now,full agreement on interpretation of the anti-corrosion performance of the film in marine environment,especially in the deep sea,has not been reached.In this work,the electrochemical performance of two-surface-state Ti-Al-Nb-Zr alloys which are treated by mechanical polishing and anodizing pre-passivation in the simulated shallow sea,1000 m and 3000 m deep sea environments,is investigated.By interpreting the electrochemical kinetic parameters,it is found that the dominant cathodic process becomes hydrogen evolution in simulated deep sea environments,but the reduction rate is restrained by high hydrostatic pressure,which arrests the passivation of the alloy.Assisted by X-ray photoelectron spectroscopy analysis,it is found that the passive film mainly consists of titanium oxides.There are intermediate oxides with non-stoichiometric ratio involved in the film formation due to the low dissolved oxygen concentration and low temperature.The results of Mott-Schottky and electrochemical impedance show that the film has n-type semiconducting property with oxygen vacancies as the main point defects.The anti-corrosion performance in simulated deep sea environments is one order of magnitude lower than that in the simulated shallow sea environment.However,from 1000 to 3000 m,the corrosion resistance is reduced very slightly.In the inner layers of the passive film and the passive film formed in simulated deep sea environments,the proportion of lowvalence titanium oxides is relatively high.The doping of low-valence titanium(Ti(Ⅱ) or Ti(Ⅲ)) results in a porous structure and ion permeability of the passive film,as well as relatively low corro sion resistance.展开更多
文摘A comprehensive examination of detrital sandstone modes from the Sylhet Trough reveals a diverse range of sub-lithic to sub-feldspathic quartz arenites.Soil samples were gathered from Dupi Gaon(Jaintiapur)in Bangladesh,followed by a thorough analysis using field examination,X-ray diffraction(XRD),X-ray fluorescence(XRF),petrography,and heavy mineral concentration analyses.Field observations revealed the soil sample varying from white to yellowish to variegated,with thicknesses ranging from 15 cm to about 4 m,and exhibiting moderate softness.XRF analysis revealed significant SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)levels in the samples,with zirconium(Zr)and copper(Cu)showing consistently high concentrations.XRD analysis identified quartz as predominant,along with muscovite,biotite,and accessory minerals like rutile and magnetite.Petrographic analysis highlighted quartz as dominant,with fractures suggesting tectonic influences,while heavy mineral separation techniques identified zircon,garnet,goethite,rutile,and magnetite.These findings provide insights into sediment provenance,depositional processes,and environ-mental conditions during the formation of the Dupi Tila Formation.The comprehensive geochemical data of the entire rock indicates that most of the sediments originated from felsic igneous sources,and also suggests a moderate to high level of weathering in the source region.Overall,the analyses suggested an in situ origin of the Dupi Tila Formation,with parent materials being predominantly detrital rather than authigenic,supported by the presence of detrital quartz and an assessment of the depositional environment,providing insights into the geological conditions of the era and potential modes of sediment transportation.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFC2105800National Natural Science Foundation of China,Grant/Award Numbers:21901084,21905106,22279041+2 种基金Higher Education Discipline Innovation Project,Grant/Award Number:B17020Specific Research Fund of the Innovation Platform for Academicians of Hainan Province,China,Grant/Award Number:YSPTZX202321Natural Science Foundation of Jilin Province,Grant/Award Number:SKL202302017.
文摘Electrocatalytic reduction of nitrate pollutants to produce ammonia offers an effective approach to realizing the artificial nitrogen cycle and replacing the energyintensive Haber-Bosch process.Nitrite is an important intermediate product in the reduction of nitrate to ammonia.Therefore,the mechanism of converting nitrite into ammonia warrants further investigation.Molecular cobalt catalysts are regarded as promising for nitrite reduction reactions(NO_(2)^(−)RR).However,designing and controlling the coordination environment of molecular catalysts is crucial for studying the mechanism of NO_(2)^(−)RR and catalyst design.Herein,we develop a molecular platform of cobalt porphyrin with three coordination microenvironments(Co-N_(3)X_(1),X=N,O,S).Electrochemical experiments demonstrate that cobalt porphyrin with O coordination(CoOTPP)exhibits the lowest onset potential and the highest activity for NO_(2)^(−)RR in ammonia production.Under neutral,nonbuffered conditions over a wide potential range(−1.0 to−1.5 V versus AgCl/Ag),the Faradaic efficiency of nearly 90%for ammonia was achieved and reached 94.5%at−1.4 V versus AgCl/Ag,with an ammonia yield of 6,498μgh^(−1)and a turnover number of 22,869 at−1.5V versus AgCl/Ag.In situ characterization and density functional theory calculations reveal that modulating the coordination environment alters the electron transfer mode of the cobalt active center and the charge redistribution caused by the break of the ligand field.Therefore,this results in enhanced electrochemical activity for NO_(2)^(−)RR in ammonia production.This study provides valuable guidance for designing adjustments to the coordination environment of molecular catalysts to enhance catalytic activity.
文摘For internal combustion engines,engines installed for transport ships,cargo ships,and fishing vessels are mainly diesel engines.The number of engines is increasing due to the development of the maritime and seafood exploitation sectors.Therefore,the high demand for petroleum fuels increases environmental pollution due to engine emissions.Reducing environmental pollution from the combustion of petroleum fuels has become a concern worldwide,especially for internal combustion engines.The exhaust gases from the engine contain harmful substances such as soot and nitrogen oxides(NO_(x)).Fuels with higher carbon content generate more soot when burned.In contrast,biofuels have low carbon and sulfur content and supply ample oxygen,which helps to reduce soot formation.For these reasons,biofuels are encouraged as alternative fuels to petroleum.Vegetable oil is one of the primary raw materials for biofuel production.This study presents a mixture of diesel and vegetable oil utilized as fuel for fishing vessels’diesel engines.The results of experimental research on a fishing vessel’s 4CHE Yanmar diesel engine when using diesel fuel mixed with coconut oil(B15,15%coconut oil,and 85%diesel)show that increasing B15 fuel injection pressure by about 10–15%compared with diesel fuel injection pressure reduces the engine’s soot emissions and increases power compared to unadjusted.This solution contributes to reducing environmental pollution from engine emissions.
基金supported by grants from the National Natural Science Foundation of China(Nos.42172339,91951205)。
文摘Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems.However,the distribution of microbial functional genes and their influencing factors in hot springs remain largely unclear.Therefore,this study investigated the microbial functional genes and their potential for controlling biogeochemical cycles(C,N,S,and P) in the hot Springs of Tengchong,China,using the Geochip method,a functional gene microarray technology.The examined hot springs have very different microbial functional genes.A total of 22 736 gene probe signals were identified,belonging to 567 functional genes and associated with 15 ecological functions,mainly involving stress response,carbon cycle,nitrogen cycle,sulfur cycle,phosphorus cycle and energy processes.The amyA,narG,dsrA and ppx genes were most abundant in carbon,nitrogen,sulfur and phosphorus cycles,respectively,and were significantly correlated with pH,temperature and SO_(4)^(2-).The diversity and abundance of detected gene probes were negatively correlated with temperature.The α-diversity(i.e.,Shannon index) was high at low temperature and low pH.Molecular functional interactions revealed by the gene connectivity levels were negatively correlated with temperature,pH and SO_(4)^(2-).These results suggested that the abundance,diversity and interactions of microbial functional genes were significantly influenced by geochemical parameters.-In addition,some genera possessed functional genes related to carbon,nitrogen,sulfur,and phosphorus cycles and can synergistically control the biogeochemical cycles of carbon,nitrogen,sulfur and phosphorus.These findings provide new insights into the functional potentials of microorganisms to participate in biogeochemical cycles and their responses to environmental factors in hot springs.
基金supported by scientific research fund of Jiangxi Provincial Social Sciences“14th Five-Year Plan”(No.23SH05).
文摘This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China Family Panel Studies(CFPS)data,1491 children(girls ratio=53.78%;average grade=6.023 years,school grade standard deviation=1.825 years).Results following multiple regression model(OLS)show that the higher the parental cognitive ability,the higher the children’s logical reasoning ability.Secondly,parental academic expectation serves as a mediator between their cognitive ability and children’s logical reasoning ability for higher logical reasoning by children.Third,a possible family environment acts as a mediator in the relationship between parents’cognitive ability and children’s logical reasoning ability to be higher.We conclude from thesefindings that parents with high cognitive abilities can enhance their children’s logical reasoning skills not only by setting higher academic expectations,but also by cultivating a supportive family environment.Thesefindings imply a need for intervention to improve family quality of life to enhance children’s thinking abilities to optimize their academic learning.
基金supported by the Institute of Information&Communications Technology Planning&Evaluation(IITP)grant funded by the Korea government(MSIT)(No.RS-2023-00235509Development of security monitoring technology based network behavior against encrypted cyber threats in ICT convergence environment).
文摘With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comprise heterogeneous networks where outdated systems coexist with the latest devices,spanning a range of devices from non-encrypted ones to fully encrypted ones.Given the limited visibility into payloads in this context,this study investigates AI-based attack detection methods that leverage encrypted traffic metadata,eliminating the need for decryption and minimizing system performance degradation—especially in light of these heterogeneous devices.Using the UNSW-NB15 and CICIoT-2023 dataset,encrypted and unencrypted traffic were categorized according to security protocol,and AI-based intrusion detection experiments were conducted for each traffic type based on metadata.To mitigate the problem of class imbalance,eight different data sampling techniques were applied.The effectiveness of these sampling techniques was then comparatively analyzed using two ensemble models and three Deep Learning(DL)models from various perspectives.The experimental results confirmed that metadata-based attack detection is feasible using only encrypted traffic.In the UNSW-NB15 dataset,the f1-score of encrypted traffic was approximately 0.98,which is 4.3%higher than that of unencrypted traffic(approximately 0.94).In addition,analysis of the encrypted traffic in the CICIoT-2023 dataset using the same method showed a significantly lower f1-score of roughly 0.43,indicating that the quality of the dataset and the preprocessing approach have a substantial impact on detection performance.Furthermore,when data sampling techniques were applied to encrypted traffic,the recall in the UNSWNB15(Encrypted)dataset improved by up to 23.0%,and in the CICIoT-2023(Encrypted)dataset by 20.26%,showing a similar level of improvement.Notably,in CICIoT-2023,f1-score and Receiver Operation Characteristic-Area Under the Curve(ROC-AUC)increased by 59.0%and 55.94%,respectively.These results suggest that data sampling can have a positive effect even in encrypted environments.However,the extent of the improvement may vary depending on data quality,model architecture,and sampling strategy.
基金Supported by "Chen Guang"Project Launched by Shanghai Municipal Education Commission and Shanghai Education Development Foundation (09CGB09)~~
文摘With the rapid development of economy, requirements on indoor environment design are getting higher and higher, but its prosperity brings ecological environment serious destruction and over consumption of resources. Under the global environment of the sustainable development, the principles of indoor environment design were analyzed ecologically and corresponding implementation methods were proposed to provide reference for energy-conservation and gas emission-reduction in the ecological system of indoor environment.
基金Supported by Institutional NRSA,clinical oncology research training program,No.T32 CA079447(Bishehsari F)the Associazione Italiana per la Ricerca sul Cancro(AIRC),Milan to Mariani-Costantini R+3 种基金the Office for Internationalization,G.d’Annunzio University,Chietithe Carichieti Foundation,ChietiMinistero dell’Istruzione,dell’Universitàe della Ricerca(MIUR),Rome,Italythe Fondazione Umberto Veronesi,Milan,Italy and the MRC(5PT57)to Vacca M
文摘Colorectal cancer(CRC)is one of the leading causes of cancer and cancer-related mortality worldwide.The disease has been traditionally a major health problem in industrial countries,however the CRC rates are increasing in the developing countries that are undergoing economic growth.Several environmental risk factors,mainly changes in diet and life style,have been suggested to underlie the rise of CRC in these populations.Diet and lifestyle impinge on nuclear receptors,on the intestinal microbiota and on crucial molecular pathways that are implicated in intestinal carcinogenesis.In this respect,the epidemiological transition in several regions of the world offers a unique opportunity to better understand CRC carcinogenesis by studying the disease phenotypes and their environmental and molecular associations in different populations.The data from these studies may have important implications for the global prevention and treatment of CRC.
文摘The purpose of this study was to evaluate the roles of different housing environments in neurological function, cerebral metabolism, cerebral infarction and neuron apoptosis after focal cerebral ischemia. Twenty-eight Sprague-Dawley rats were divided into control group （CG） and cerebral ischemia group, and the latter was further divided into subgroups of different housing conditions： standard environment （SE） subgroup, individual living environment （IE） subgroup, and enriched environment （EE） subgroup. Focal cerebral ischemia was induced by the middle cerebral artery occlusion （MCAO）. Beam walking test was used to quantify the changes of overall motor function. Cerebral infarction and cerebral metabolism were studied by in vivo magnetic resonance imaging and 1H-magnetic resonance spectra, respectively. Neuron necrosis and apoptosis were detected by hematoxylin-eosin and TUNEL staining methods, respectively. The results showed that performance on the beam-walk test was improved in EE subgroup when compared to SE subgroup and IE subgroup. Cerebral infarct volume in IE subgroup was significantly larger than that in SE subgroup （P〈0.05） and EE subgroup （P〈0.05） on day 14 after MCAO. NAA/Cr and Cho/Cr ratios were lower in MCAO groups under different housing conditions as compared to those in CG （P〈0.05）. NAA/Cr ratio was lower in IE subgroup （P〈0.05） and higher in EE subgroup （P〈0.05） than that in SE subgroup. NAA/ Cr ratio in EE was significantly higher than that in IE subgroup （P〈0.05）. Cho/Cr ratio was decreased in MCAO groups as compared to that in CG （P〈0.05）. A significant decrease in normal neurons in cerebral cortex was observed in MCAO groups as compared to CG （P〈0.05）. The amount of normal neurons was less in IE subgroup （P〈0.05）, and more in EE subgroup （P〈0.05） than that in SE subgroup after MCAO. The amotmt of normal neurons in EE subgroup was significantly more than that in IE subgroup after MCAO （P〈0.05）. The ratio of TUNEL-positive neurons in EE was significantly lower than that in SE subgroup （P〈0.05） and IE subgroup （P〈0.05）. Correlation analysis showed that the beam walking test was negatively correlated with NAA/Cr ratio （P〈0.05）. Cerebral infarct volume was negatively correlated with both NAA/Cr ratio （P〈0.01） and Cho/Cr ratio （P〈0.01）. The amount of normal cortical neurons was positively correlated with both NAA/Cr ratio （P〈0.0I） and Cho/Cr ratio （P〈0.05）. The TUNEL-positive neurons showed a negative correlation with both NAA/Cr ratio （P〈0.01） and Cho/Cr ratio （P〈0.01）. This study goes further to show that EE may improve neurological functional deficit and cerebral metabolism, decrease cerebral infarct volume, neuron necrosis and apoptosis, while IE may aggravate brain damage after MCAO.
基金financially supported by the President of the Russian Federation (No. 1159.2014.5)the Far Eastern Branch of the Russian Academy of Sciences (No. 15-1-2-013-2)
文摘The first data of geochemical study of the Benevka Section cherty rocks belonging to the Taukha terrane of the Sikhote-Alin Late Jurassic-Early Cretaceous accretionary prism, Russia Far East are presented. These data demonstrate essential distinctions of major, trace and rare earth element concentrations in different parts of the measured stratigraphic section. The lower chert horizons exhibit high Fe2O3 and MnO contents, low concentrations of Al2O3 and TiO2, relatively high V/Y ratio, and extremely low value of negative Ce anomaly. In contrast the upper horizons composed of clayey cherts and siliceous mudstones are characterized by high Al2O3, TiO2 and K2O contents, low Fe2O3 and MnO values, low V/Y ratio, and slightly negative Ce anomaly. In the middle part of the Benevka Section, in which cherts gradually changed to clayey cherts, intermediate geochemical characteristics are present. Based on these data obtained the depositional environments correspond to proximal to the spreding ridge, open-ocean and near continental margin regimes were successfully reconstructed from bottom to top of the Benevka Section, that indicate that significant horizontal movement took place of the sea-floor, on which the cherts were deposited.
基金supported mainly by the National Natural Science Foundation of China (No. 40772143)the Special Fund of the State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciencesthe Faculty of Science,Mahasarakham University
文摘Geochemical analysis reveals that Middle Triassic radiolarian cherts from northern Thailand,including Chiang Dao,Lamphun and Den Chai,are of biogenic origin.These cherts present slightly high SiO2 content which was possibly modified by diagenetic alteration and migration processes as indicated by negative correlation between SiO2 and most of the other major elements.The relatively high content of Cr,Zr,Hf,Rb and Th and high positive correlation of these elements with Al and Ti from the majority of cherts suggest a close relation to terrigenous component.The Ce anomaly（Ce/Ce＊） with geometric means ranging from 0.85 to 0.93 is compatible with that of continental margin composi-tion（0.67-1.52） from Murray et al.（1990） which is also consistent with low Eu anomalies（Eu/Eu＊,0.91-0.94）.Moreover,the slightly low ratios of La and Ce NASC normalized（Lan/Cen,0.91-0.94） and the low LREE and HREE ratios in most of our samples（Lan/Ybn,0.62-0.85） are in agreement with the continental margin.The result from Lan/Cen vs.Al2O3/（Al2O3＋Fe2O3） discrimination diagrams also supports the continental margin（residual basin,s.str.） interpretation.These geochemical results are compatible with geological evidence,which suggest that during the Middle Triassic,radio-larian cherts were deposited within a deeper part of a residual basin in which an accommoda-tion space was possibly controlled by faults un-der extensional regime subsequent to Late Variscan（Permian） orogeny.Paleogeographi-cally,the main Paleotethys which closed during Late Triassic should be located further to the west of these study localities.This scenario is in agreement with the current view of the Tethys in this part of the world.
基金supported by National 305 Project(2007BAB25B05,2011BAB06B02- 04)NSFC grant(40925006,40772045,40572047)111 Project(B07011)
文摘In the southwestern Tianshan,the geologic ages of many strata and their depositional environments are still poorly constrained because of complex structures.The Mada＇er area is located in the Kuokesaleling belt,Southwestern Tianshan.The cherts from the former Wupata＇erkan Group contain abundant radiolarian fossils,including 10 species which are identified as late Devonian to early Carboniferous in age.Eleven chert samples have SiO_2 contents ranging from 88.80 wt%to 93.28 wt%, and 2.02 wt%to 3.72 wt%for Al_2O_3.The SiO_2/Al_2O_3 ratios of all samples vary from 23.84 to 46.11, much lower than those of the pure cherts（80-1400）.These values suggest that the cherts contain high ratios of terrigenous materials.The Al_2O_3/（Al_2O_3＋Fe_2O_3）ratios vary between 0.64 and 0.77,whereas V and Cu concentrations range from 10.92 ppm to 26.7 ppm and from 2.15 ppm to 34.1 ppm respectively. The Ti/V ratios vary from 25.53 to 44.93.The total REE concentrations of the cherts are between 30.78 ppm and 59.26 ppm,averaging 45.46 ppm.The（La/Ce）_N ratios range from 0.81 to 1.12,and 0.88-1.33 for（La/Yb）_N,averaging 1.09,which suggests a continental margin environment.Consequently,it is inferred that the cherts formed in a residual sea environment during the late Devonian to early Carboniferous time,which suggests that the collision between the Karakum-Tarim and Kazakhstan-Junggar plates did not occur at the time.In addition,the regional geological information indicates that the study area experienced a post-collision stage during the early Permian,and thus it is likely that the collision between the two plates took place in the late Carboniferous.
基金Project supported by the Key Scientific and Technological Project of Hubei Province, China (2007AA301C51)
文摘By means of techniques such as inductively coupled plasma-mass spectrometry （ICP-MS） and X-ray fluorescence spectrometry （XRF）,REE geochemical characteristics and depositional environment of the black shales in Baiguoyuan Ag-V deposit,Xingshan,Hubei Province,were studied in this work. The black shales in a typical TC5 profile of Doushantuo Formation of upper Sinian period were obviously enriched in REE,especially in LREE. The REE patterns of the investigated samples normalized by Post Archean Australian Shale （PAAS） showed a flat or slight rightward inclination. The characteristic elements,their ratio and correlation diagrams showed that it should be hot-water deposit and the black shale in the study area was of a sedimentary origin. Redox sensitive metal elements pattern,trace elements index measurement in anoxic environment,Ce anomaly and δEu negative anomaly showed that the deposit environment of the black shales was a reducing and anoxic one and a slight change of the sea level could be identified. The samples relatively focused on the superimposed area of sedimentary rock and basalt in the diagram of La/Yb-ΣREE and La/Yb-Ce/La. So there might be accession of hot-water sedimentation during the period of the formation of the black rock series,mostly in normal terrigenous sedimentation with the participation of deep hot-water deposit.
文摘: In the Hunan-Guizhou-Guangxi area there have developed very thick bedded siliceous rocks of the late Sinian. The rocks have a fairly pure composition, with an average content of siliceous minerals exceeding 95%. They are relatively rich in Fe and Mn, and poor in Al, Ti and Mg. The Fe/Ti, (Fe+Mn)/Ti, Al/(Al+Fe+Mn) and U/Th ratios and the Al-Fe-Mn and Fe-Mn-(Ni+Co+Cu)×10 triangle diagrams all show that they are hydrothermal sedimentary siliceous rocks. In the rocks the total amount of REEs is low, the δCe shows an obvious negative anomaly and the δEu a weak anomaly, and LREE>HREE, all indicating that they are products of hydrothermal processes. The δ30Si and δ18O values, as well as the formation temperature of the rocks all clearly show that the silica forming the rocks comes from hot water. Besides, analyses of the depositional environment of the rocks using the MnO/TiO2 ratio and the δCe and δ30Si values yield the same conclusion that they are formed in environments from continental marginal slopes of a bathyal environment to oceanic basins of a deep-sea environment.
基金This work was financially supported by the National Key Basic Research Program of China(Grant No.2017-JCJQ-ZD-024).
文摘Titanium alloy Ti-Al-Nb-Zr has high specific strength and becomes a promising structural material used in the deep sea.The excellent corrosion resistance of the alloy is derived from the protective passive film formed on its surface.By now,full agreement on interpretation of the anti-corrosion performance of the film in marine environment,especially in the deep sea,has not been reached.In this work,the electrochemical performance of two-surface-state Ti-Al-Nb-Zr alloys which are treated by mechanical polishing and anodizing pre-passivation in the simulated shallow sea,1000 m and 3000 m deep sea environments,is investigated.By interpreting the electrochemical kinetic parameters,it is found that the dominant cathodic process becomes hydrogen evolution in simulated deep sea environments,but the reduction rate is restrained by high hydrostatic pressure,which arrests the passivation of the alloy.Assisted by X-ray photoelectron spectroscopy analysis,it is found that the passive film mainly consists of titanium oxides.There are intermediate oxides with non-stoichiometric ratio involved in the film formation due to the low dissolved oxygen concentration and low temperature.The results of Mott-Schottky and electrochemical impedance show that the film has n-type semiconducting property with oxygen vacancies as the main point defects.The anti-corrosion performance in simulated deep sea environments is one order of magnitude lower than that in the simulated shallow sea environment.However,from 1000 to 3000 m,the corrosion resistance is reduced very slightly.In the inner layers of the passive film and the passive film formed in simulated deep sea environments,the proportion of lowvalence titanium oxides is relatively high.The doping of low-valence titanium(Ti(Ⅱ) or Ti(Ⅲ)) results in a porous structure and ion permeability of the passive film,as well as relatively low corro sion resistance.
