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Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-Life and Aroma Volatile Compounds of Oriental Sweet Melons(Cucumis melo var.makuwa Makino) 被引量:11
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作者 BAI Xiao-hang TENG Lu-hua +1 位作者 Lü De-qing QI Hong-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第1期217-227,共11页
Compared to other melon types, oriental sweet melon (Cucumis melo var. makuwa Makino) is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of ... Compared to other melon types, oriental sweet melon (Cucumis melo var. makuwa Makino) is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co- treatment of enhanced freshness formulation (EFF) and 1-methylcyclopropene (1-MCP) on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars (Yumeiren and Tianbao) during storage. The melons were stored in incubators with temperature of 15~C and a relative humidity of 85% for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit firmness, water content and soluble solids content. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities showed fluctuations in treated melons, while lipoxygenase (LOX) activity (P〈0.01) and malondialdehyde (MDA) content (P〈0.05) decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneficial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds. 展开更多
关键词 oriental sweet melon enhanced freshness formulation l-methylcyclopropene aroma volatile compounds shelf-life
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Predication of Fhhh potential in PTA wastewater treatment 被引量:1
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作者 CHENGShu-pei SHILei ZHANGXu-xiang YANJun DINGZhong-hai HAOChun-bo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期1-4,共4页
Ebis is the intelligent environmental biotechnological informatics software developed for judging the effectiveness of the microorganism strain in the industrial wastewater treatment system(IWTS) at the optimal status... Ebis is the intelligent environmental biotechnological informatics software developed for judging the effectiveness of the microorganism strain in the industrial wastewater treatment system(IWTS) at the optimal status. The parameter, as the objective function for the judgment, is the minimum reactor volume( V _ min ) calculated by Ebis for microorganism required in wastewater treatment. The rationality and the universality of Ebis were demonstrated in the domestic sewage treatment system(DSTS) with the data published in USA and China at first,then Fhhh strain's potential for treating the purified terephthalic acid(PTA) was proved. It suggests that Ebis would be useful and universal for predicating the technique effectiveness in both DSTS and IWTS. 展开更多
关键词 SOFTWARE STRAIN POTENTIAL predication purified terephthalic acid wastewater
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Chitosan Extends the Shelf-life of Filleted Tilapia (Oreochromis niloticus) During Refrigerated Storage 被引量:9
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作者 CAO Rong LIU Qi +1 位作者 YIN Bangzhong WU Biao 《Journal of Ocean University of China》 SCIE CAS 2012年第3期408-412,共5页
Shelf-life extension of aquatic products is of significant economical importance. To determine the potential effect of chitosan on the shelf-life of filleted tilapia, this study analyzed the bacterial community divers... Shelf-life extension of aquatic products is of significant economical importance. To determine the potential effect of chitosan on the shelf-life of filleted tilapia, this study analyzed the bacterial community diversity in fresh and spoiled tilapia fillets stored at (4 ± 1)℃ and examined the antimicrobial activity of chitosan against relevant bacteria isolates. Results showed that Pseudomonas (20%) and Aeromonas (16%) were abundant in fresh tilapia fillets, whereas Pseudomonas (52%), Aeromonas (32%) and Staphylococcus (12%) were dominant in the spoiled samples. Chitosan showed wide-spectrum antibacterial activity against bacteria isolated from tilapia and 5.0 g L-1 chitosan was selected for application in preservation. We further determined the shelf-life of chitosan-treated, filleted tilapia stored at (4 ± 1)℃ based on microbiological, biochemical and sensory analyses. Results showed that the shelf-life of chitosan-treated, filleted tilapia was extended to 12 d, whereas that of untreated, control samples was 6 d. These indicate that chitosan, as a natural preservative, has great application potential in the shelf-life extension of tilapia fillets. 展开更多
关键词 Oreochromis niloticus bacterial flora chitosan refrigeration shelf-life
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Sodium dehydroacetate treatment prolongs the shelf-life of'Kyoho'grape by regulating oxidative stress and DNA methylation 被引量:1
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作者 GUO Da-long LIU Hai-nan +2 位作者 WANG Zhen-guang GUO Li-li ZHANG Guo-hai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第5期1525-1533,共9页
In this study,we tested the ability of sodium dehydroacetate(SD)to extend the shelf-life of‘Kyoho’grape.Among the different concentrations of SD tested(0,0.01,0.1 and 1.0 mmol L^(-1)),0.01 mmol L^(-1) SD was the mos... In this study,we tested the ability of sodium dehydroacetate(SD)to extend the shelf-life of‘Kyoho’grape.Among the different concentrations of SD tested(0,0.01,0.1 and 1.0 mmol L^(-1)),0.01 mmol L^(-1) SD was the most effective in prolonging the shelf-life of‘Kyoho’grape.Compared with the control,the weight loss rate,browning index and hydrogen peroxide(H_(2)O_(2))and malonaldehyde contents were significantly lower in the 0.01 mmol L^(-1) SD treatment,whereas the healthy berry rate,berry firmness,total soluble solids(TSS)content,ascorbic acid content and superoxide dismutase(SOD)activity were significantly higher.In addition,an analysis of‘Kyoho’grape DNA using methylation sensitive amplification polymorphism(MSAP)markers showed that the average DNA methylation level was significantly higher in the 0.01 mmol L^(-1) SD treatment than in the control.Together,these results indicate that 0.01 mmol L^(-1) SD could be used to extend the shelf-life of‘Kyoho’grape.Moreover,a strong connection between reactive oxygen species(ROS)metabolism and DNA methylation change during storage was revealed. 展开更多
关键词 GRAPE sodium dehydroacetate DNA methylation MSAP shelf-life
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Predication of plasma concentration of remifentanil based on Elman neural network 被引量:1
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作者 汤井田 曹扬 +1 位作者 肖嘉莹 郭曲练 《Journal of Central South University》 SCIE EI CAS 2013年第11期3187-3192,共6页
Due to the nature of ultra-short-acting opioid remifentanil of high time-varying,complex compartment model and low-accuracy of plasma concentration prediction,the traditional estimation method of population pharmacoki... Due to the nature of ultra-short-acting opioid remifentanil of high time-varying,complex compartment model and low-accuracy of plasma concentration prediction,the traditional estimation method of population pharmacokinetics parameters,nonlinear mixed effects model(NONMEM),has the abuses of tedious work and plenty of man-made jamming factors.The Elman feedback neural network was built.The relationships between the patients’plasma concentration of remifentanil and time,patient’age,gender,lean body mass,height,body surface area,sampling time,total dose,and injection rate through network training were obtained to predict the plasma concentration of remifentanil,and after that,it was compared with the results of NONMEM algorithm.In conclusion,the average error of Elman network is 6.34%,while that of NONMEM is 18.99%.The absolute average error of Elman network is 27.07%,while that of NONMEM is 38.09%.The experimental results indicate that Elman neural network could predict the plasma concentration of remifentanil rapidly and stably,with high accuracy and low error.For the characteristics of simple principle and fast computing speed,this method is suitable to data analysis of short-acting anesthesia drug population pharmacokinetic and pharmacodynamics. 展开更多
关键词 Elman neural network REMIFENTANIL plasma concentration predication model
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Effect of Packaging Conditions on Shelf-Life of Mortadella Made with Citrus Fibre Washing Water and Thyme or Rosemary Essential Oil 被引量:1
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作者 Manuel Viuda-Martos Yolanda Ruiz-Navajas +1 位作者 Juana Fernández-López José Angel Pérez-álvarez 《Food and Nutrition Sciences》 2011年第1期1-10,共10页
The “elimination” of chemical additives used in a wide variety of foods is demanded, while “natural” additives are seen as a benefit for both quality and safety. Researchers are looking for new sources of ingredie... The “elimination” of chemical additives used in a wide variety of foods is demanded, while “natural” additives are seen as a benefit for both quality and safety. Researchers are looking for new sources of ingredients and/or additives. The aim of this work was to study the effect of 1) the addition of 5.00% citrus fibre washing water (CFWW) and 0.02% rosemary essential oil (REO) or 0.02 % thyme essential oil (TEO) and 2) storage conditions on the chemical, microbe- ological and sensorial properties of mortadellas, a bologna-type sausage. CFWW + REO or CFWW + TEO samples stored in vacuum packaging showed the lowest TBA values. The resulting products were packed either in vacuum, modified atmosphere or air pouches and stored for 24 days. Lipid oxidation was assessed by the TBA method, while a quantitative descriptive analysis was carried out for sensory evaluation. Microbiological counts were also determined. CFWW + REO samples stored in vacuum packaging showed the lowest counts of aerobic and lactic acid bacteria. The sensory evaluation provided similar scores for CFWW + REO and CFWW + TEO samples. The lowest scores were obtained for control mortadella stored in air packaging. The addition of citrus fibre washing water and spice essential oils is a technologically viable alternative in emulsified meat products, since they improve customer acceptance and have desirable effects as regards oxidative stability and reduced microbial growth, which contributes to prolonging their shelf-life. 展开更多
关键词 ESSENTIAL OILS COOKED MEAT Co-Products shelf-life
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Sand Storage, Extending the Shelf-Life of Fresh Sweetpotato Roots for Home Consumption and Market Sales 被引量:1
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作者 Putri Emawati Abidin John Kazembe +4 位作者 Richard A. Atuna Francis Kwaku Amagloh Kwabena Asare EricKuuna Dery Edward Ewing Carey 《Journal of Food Science and Engineering》 2016年第4期227-236,共10页
Uni-modal rainfall pattern has long dry spell wherein sweetpotato is scarce, expensive but cheap at harvest. The crop is mostly consumed, processed or sold. Extending shelf-life of roots is crucial for Malawi and Nort... Uni-modal rainfall pattern has long dry spell wherein sweetpotato is scarce, expensive but cheap at harvest. The crop is mostly consumed, processed or sold. Extending shelf-life of roots is crucial for Malawi and Northern Ghana as the crop has high value. Trials were conducted in the countries at the community level. In the dry season, temperature is cool in Malawi while warm in Ghana, but thru harmattan, the night is cool with low relative humidity. In Malawi, orange-fleshed sweetpotato Zondeni var., white and yellow types were assessed in three types of storage, Afghan ventilated pit store, storage in dry sand of pit-steps, and of a granary In Ghana, local moistened heap and sandbox were compared. In Malawi, weight losses were calculated relative to the quantity stored at start, it was not cumulative. At 1.5 months no significant difference was among treatments. By 3.5 months the pit-steps method emerged to be superior and continued to 6.5 months. Losses in granary were due to shriveling, in the pit-stepsdue to termites and rats, and in ventilated pit due to termites, rats and Java black rot. Sprouting was high in pit-steps, but it was simply removed and roots returned to storage. At 6.5 months, the beta-carotene of Zondeni roots was traceable. Farmers gained high price when selling them as roots were scarce. Women favored the pit-steps because it was manageable. In Ghana, the sandbox was superior to local moistened heap. Methods designed were suitable for home consumption, but will require modification for commercialization. 展开更多
关键词 Sand storage SWEETPOTATO orange-fleshed sweetpotato local knowledge shelf-life of storage roots beta-carotene.
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Predication of Atmospheric VLE for the Ternary System Dimethyl Carbonate-Methanol-Furfural by Using the Wilson Equation
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作者 张立庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2002年第4期89-91,共3页
The vapor-liquid equilibrium of Dimethyl Carbonate-Methanol-Furfural under atmospheric pressure from DMC-CH 3OH,DMCC 5H 4O 2,CH 3OH-C 5H 4O 2 binary systematic VLE data is calculated,by using C ++(VC6.0) pr... The vapor-liquid equilibrium of Dimethyl Carbonate-Methanol-Furfural under atmospheric pressure from DMC-CH 3OH,DMCC 5H 4O 2,CH 3OH-C 5H 4O 2 binary systematic VLE data is calculated,by using C ++(VC6.0) programming language and Wilson equation.It provided important VLE data to set up mathematic models of extraction-rectifying separation of DMC and methanol by using furfural as extraction reagent.So the results can be used for chemical engineering calculation. 展开更多
关键词 dimethyl Carbonate METHANOL FURFURAL VLE predication Wilson equation
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Optimal predication of double-star position/SINS based on discrete integration
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作者 林雪原 何友 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第2期179-182,共4页
Aiming at Double-Star positioning system's shortcomings of delayed position information and easy exposition of the user as well as the error increase of the SINS with the accumulation of time, the integration of D... Aiming at Double-Star positioning system's shortcomings of delayed position information and easy exposition of the user as well as the error increase of the SINS with the accumulation of time, the integration of Double-Star positioning system and the SINS is one of the developing directions for an integrated navigation system. This paper puts forward an optimal predication method of Double-Star/SINS integrated system based on discrete integration, which can make use of the delayed position information of Double-Star positioning system to optimally predicate the integrated system, and then corrects the SINS. The experimental results show that this method can increase the user's concealment under the condition of assuring the system's accuracy. 展开更多
关键词 discrete integration optimal predication Double-Star positioning system SINS
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Elimination of Foodborne Pathogens in Seafoods by Irradiation: Effects on the Quality and Shelf-Life
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作者 Ismail Yuksel Genc Abdullah Diler 《Journal of Food Science and Engineering》 2013年第2期99-106,共8页
Animal originated contamination is the main problem of public health and causes human suffering all over the world. Nowadays, radiation technology is used on foods and yielded with positive results. Gamma radiation ca... Animal originated contamination is the main problem of public health and causes human suffering all over the world. Nowadays, radiation technology is used on foods and yielded with positive results. Gamma radiation causes damage in the structure of bacterial DNA and cell walls. This irritation can lead to decrease in bacterial growth such as spoilage and pathogenic organisms (i.e, Salmonella spp., Bacillus cereus, Listeria monocytogenes, Yersinia enterocolitica, Staphylococcus aureus, Escherichia coli O 157:H7) by this means, increased quality and shelf-life can be obtained. However, for the maintaining organoleptic and nutritional quality, it is an obligation to achive the lowest levels of doses according to chemical, physical, microbiological properties of the product. Radiation energy can lead to radiolytic products from lipids, proteins and water which are the maj or components of seafoods. Another problem in seafood industry is quality losses at the retail and distribution. Time-temperature integrations are the major factors affecting the bacterial growth and enzymatic activity on the loss of seafood quality. The purpose of this review is to summarize the available information on the elimination of some food pathogens by irradition, which emphasize the effects of gamma irradiation on the quality and shelf-life of seafoods. 展开更多
关键词 Gamma radiation SEAFOODS PATHOGEN QUALITY shelf-life.
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Fungal Population Dynamics in Ready-to-eat Salads During a Shelf-life in Italy
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作者 Ugo De Corato 《Journal of Agricultural Science and Technology(A)》 2012年第4期569-576,共8页
The aim of this work was to investigate the fungal population dynamics in ready-to-eat bagged samples of rocket (Diplotaxis spp.), lettuce baby leaf (Lactuca sativa L.) and "songino" (Valerianella olitoria L.)... The aim of this work was to investigate the fungal population dynamics in ready-to-eat bagged samples of rocket (Diplotaxis spp.), lettuce baby leaf (Lactuca sativa L.) and "songino" (Valerianella olitoria L.) during a shelf-life, in order to evaluate the effects of the storage length and season of production on the spoilage processes. The incidence of toxigenic moulds was particularity studied in order to evaluate a potential production of mycotoxins and allergenic conidia. A total of 900 samples collected from 10 Italian trademarks were analyzed at the 2nd, 5th and 8th day after the packaging in the spring and summer. A very high number of fungi was found and a great variability of moulds and yeasts at the 1 st day of sampling was observed. Regarding to season of production, any seasonal effect on the moulds and yeasts has been observed, but the moulds detected belonged to different species in relation to season. Regarding to storage length, the yeasts and moulds did not showed significant variations during a shelf-life. In relation to vegetable species, the lettuce resulted always less contaminated with respect to other salads, and the rocket presented 1-2 Log cfu/g of increasing in the level of moulds. Regarding to fungi species, the yeasts were significantly predominant respect to moulds. Finally, the toxigenic moulds Aspergillusflavus and Penicillium italicum were found in all the types of salad in the summer, and their growth during the storage at low temperature represented a potential hazard for the mycotoxins and allergenic conidia production in these commodities. 展开更多
关键词 Fungal population dynamic ready-to-eat vegetable shelf-life toxigenic mould yeast.
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Application of constrained sparse spike inversion in reservoir predication:a case study of Oriente Basin in South America
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作者 WANG Qing LU Zhanguo 《Global Geology》 2011年第2期87-93,共7页
In the conditions of low Signal-to-Noise Ratio(SNR) of seismic data and a small quality of log information,the consequences of seismic interpretation through the impedance inversion of seismic data could be more preci... In the conditions of low Signal-to-Noise Ratio(SNR) of seismic data and a small quality of log information,the consequences of seismic interpretation through the impedance inversion of seismic data could be more precise. Constrained sparse spike inversion(CSSI) has advantage in oil and gas reservoir predication because it does not rely on the original model. By analyzing the specific algorithm of CSSI,the accuracy of inversion is controlled. Oriente Basin in South America has the low amplitude in geological structure and complex lithologic trap. The well predication is obtained by the application of CSSI. 展开更多
关键词 CSSI reservoir predication control parameters lower frequency model impedance inversion
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Sequential Predication
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作者 Eugeniusz Wojciechowski 《Journal of Philosophy Study》 2015年第5期244-256,共13页
Vladimir Markin proposes a certain construction---a generalisation of syllogistic--in which he uses the constant @ with indef'mite arity. The atomic formulae are of the following sort: S1S2 ...Sm@P1P2...Pn, where re... Vladimir Markin proposes a certain construction---a generalisation of syllogistic--in which he uses the constant @ with indef'mite arity. The atomic formulae are of the following sort: S1S2 ...Sm@P1P2...Pn, where re+n〉0. The standard syllogistic functors are here interpreted as follows: SAP=: S@P SeP=: SP@ SIP=: -SP@ SOP=: ~S@P Markin constructs a system of Fundamental Syllogistic (FS) with constant @ in an axiomatic way. Based on Markin's idea, we propose two constructions, which are formulations of the system of sequential predication built upon the quantifier-less calculus of names. The first one includes the FS system. The second one is enriched with individual variables and, among other things, allows including sequences of individual names in which one has to do with enumerative functors. The counterpart of Hao Wang's algorithm holds in the first system extended with negative terms. 展开更多
关键词 sequential predication generalization of syllogistic quantifier.less calculus of names Hao Wang'salgorithm
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A Time Dependent Inventory Model for Exponential Demand Rate with Constant Production Where Shelf-Life of the Product Is Finite
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作者 Mohammad Ekramol Islam Shirajul Islam Ukil Md. Sharif Uddin 《Open Journal of Applied Sciences》 2016年第1期38-48,共11页
In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considerin... In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considering those products which have finite shelf-life. The model also considers the small amount of decay. Without having any sort of backlogs, production starts. Reaching at the desired level of inventories, it stops production. After that due to demands along with the deterioration of the items it initiates its depletion and after certain periods the inventory gets zero. The decay of the products is level dependent. The objective of this paper is to find out the optimum inventory cost and optimum time cycle. The model has also been justified with proving the convex property and by giving a numerical example. 展开更多
关键词 Production Inventory shelf-life Time Dependent Demand Class Production Rate
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A Study of Nominal Predicate Sentences Under the Framework of Cognitive Grammar
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作者 ZOU Wen-jie GAO Wen-cheng 《Journal of Literature and Art Studies》 2023年第9期704-707,共4页
Cognitive grammar,as a linguistic theory that attaches importance to the relationship between language and thinking,provides us with a more comprehensive way to understand the structure,semantics and cognitive process... Cognitive grammar,as a linguistic theory that attaches importance to the relationship between language and thinking,provides us with a more comprehensive way to understand the structure,semantics and cognitive processing of noun predicate sentences.Therefore,under the framework of cognitive grammar,this paper tries to analyze the semantic connection and cognitive process in noun predicate sentences from the semantic perspective and the method of example theory,and discusses the motivation of the formation of this construction,so as to provide references for in-depth analysis of the cognitive laws behind noun predicate sentences. 展开更多
关键词 nominal predicate sentences cognitive grammar SEMANTICS
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胶东金矿与中生代区域性花岗岩关系及成矿预测和找矿方向 被引量:1
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作者 王来明 王金辉 +8 位作者 任天龙 于晓卫 张文 李瑞翔 陶有兵 杨振毅 王立功 刘汉栋 郭瑞鹏 《山东国土资源》 2024年第3期6-22,共17页
胶东地区是世界著名的金矿资源基地,截至2023年6月已累计探明金矿资源量已达5757余吨。与金矿成矿密切的中生代花岗岩分布广泛,岩石类型多样,也是山东省最发育、最典型的地区。本文对胶东地区金矿与中生代区域性花岗岩空间展布、形成时... 胶东地区是世界著名的金矿资源基地,截至2023年6月已累计探明金矿资源量已达5757余吨。与金矿成矿密切的中生代花岗岩分布广泛,岩石类型多样,也是山东省最发育、最典型的地区。本文对胶东地区金矿与中生代区域性花岗岩空间展布、形成时代和形成环境等关系进行了分析研究。区域性广泛分布的中生代花岗岩为晚侏罗世玲珑期(166~146 Ma)、早白垩世早期郭家岭期(135~123 Ma)、早白垩世晚期伟德山期(123~110 Ma)和崂山期(118~108 Ma),研究认为区域性岩浆事件一般持续10 Ma左右,而重熔型花岗岩一般持续20 Ma,反映了由基底岩石熔融到侵入结晶的2个阶段,它有一个由基底固体岩石熔融的过程,大致也需要10 Ma,既固体岩石熔融10 Ma,熔浆活动上侵结晶10 Ma。玲珑期重熔型花岗岩是扬子板块和华北板块碰撞的期后产物,郭家岭期岩浆事件代表了中国东部中生代构造体制转换的开始,伟德山期岩浆事件代表了构造体制转换的高峰期,崂山期岩浆事件代表了构造体制转换的结束期。86.8%的金矿赋存在玲珑期花岗岩中,6.9%的金矿赋存于郭家岭期花岗岩中,玲珑期花岗岩和郭家岭期花岗岩Au元素背景值明显高于伟德山期花岗岩和崂山期花岗岩。矿石硫与玲珑期花岗岩、郭家岭期花岗岩范围相近,特别是与玲珑期花岗岩大范围重叠,具有岩浆热液硫同位素变化小的特点,说明矿石硫主要源为玲珑期花岗岩、郭家岭期花岗岩。矿石铅主要为再活化的下地壳铅,即前寒武纪结晶基底铅,有幔源铅加入。金矿成矿年龄有162~146 Ma、133~120 Ma、120~115 Ma、112~105 Ma共4个区间范围,与胶东地区四期区域性花岗岩形成时间对应,成矿年龄一般晚于成岩年龄3~5 Ma。根据胶东金矿及多金属矿与岩浆热液事件对应关系,划分为玲珑金成矿期、郭家岭金成矿期、伟德山金及多金属成矿期和崂山多金属成矿期。胶东地区金矿主要是新太古代变质地层和古元古代底部片岩层位经过重熔作用金元素活化、迁移、富集和郭家岭期岩浆作用成矿。基于以上成矿作用认识,根据地球化学块体理论,对胶东金矿潜力进行了估算,胶东地区3000 m以浅金矿潜力约为1.8万t,同时对胶西北深部金矿进行了系统预测,预测3000 m以浅金资源量3997 t,5000 m以浅7497 t。通过地质综合研究,栖霞地区中新太古代变质岩下部有隐伏玲珑期花岗岩,根据金矿主要赋存在玲珑期花岗岩中的空间展布,S、Pb等同位素以及玲珑期花岗岩是金矿成矿直接围岩或母岩的认识,该地区变质岩中发育众多的石英脉型中小型金矿和矿(化)点,可能是浅部或顶部矿体的表现,认为该地区具有良好的成矿背景和潜力,是胶东地区今后金矿找矿的重要地区和方向。并建议在该地区部署地震和大功率激电剖面及地质科研钻探,查清一系列NE向断裂和地质结构,为金矿找矿提供科学依据。 展开更多
关键词 金矿 中生代花岗岩 成矿预测 找矿方向 胶东地区
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流水句形成的顺序象似性句法机制 被引量:1
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作者 翁义明 肖清敏 《信阳师范学院学报(哲学社会科学版)》 2024年第1期121-126,共6页
文章基于语言顺序象似性的基本原则,从语言类型学的视角通过实例语料的分析,发现汉语句子中的定语、状语等修饰语在遵循顺序象似性原则的情形下,可自由不加标记地转换成并列小句,从修饰语位置提升为与主句并列的述谓结构,这是汉语流水... 文章基于语言顺序象似性的基本原则,从语言类型学的视角通过实例语料的分析,发现汉语句子中的定语、状语等修饰语在遵循顺序象似性原则的情形下,可自由不加标记地转换成并列小句,从修饰语位置提升为与主句并列的述谓结构,这是汉语流水句形成的主要内在机制与形式手段。 展开更多
关键词 流水句 顺序象似性 句法成分 述谓功能
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气候变化对厦门市恙虫病发病影响的研究
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作者 柯雪梅 陈娇娜 +4 位作者 马姗姗 伍思翰 蔡春香 王小燕 黄仕杰 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第10期965-970,共6页
目的探讨厦门市气象因素对恙虫病发病的影响。方法收集厦门市2005-2023年的厦门市恙虫病和气象因素数据,采用Spearman相关性分析方法分析恙虫病发病与气象参数之间的相关关系,采用非线性回归法分析恙虫病与气象参数的数量关系。结果2005... 目的探讨厦门市气象因素对恙虫病发病的影响。方法收集厦门市2005-2023年的厦门市恙虫病和气象因素数据,采用Spearman相关性分析方法分析恙虫病发病与气象参数之间的相关关系,采用非线性回归法分析恙虫病与气象参数的数量关系。结果2005-2023年厦门市恙虫病发病呈先上升后下降的趋势,发病最高年份在2014-2016年,发病高峰季节集中在6-10月份。厦门市恙虫病月发病数与日最低气温(r=0.637,P<0.001)、日平均气温(r=0.627,P<0.001)、日最高气温(r=0.612,P<0.001)、日照时间(r=0.405,P<0.001)、平均相对湿度(r=0.346,P<0.001)及日降水量(r=0.207,P=0.002)呈正相关;与平均气压成负相关(r=-0.549,P<0.001);与平均风速无相关。厦门市恙虫病与气象指标模型回归方程为y=-206.229-11.042x_(1)+0.346x_(1)^(2)+6.266x_(2)-0.106x_(2)^(2)+5.704x_(3)-0.171x_(3)^(2)+0.502x_(4)+0.024x_(4)^(2)-0.667 x_(5)+0.006 x_(5)^(2)+0.190x_(6)-0.019x_(6)^(2)+0.184x_(7),决定系数为0.473。增加全市某大型公园人流量(x_(8))作为因变量纳入多元非线性回归分析,模型回归方程为y=-433.869-11.503x_(1)+0.381x_(1)^(2)+9.150x_(2)-0.197x_(2)^(2)+3.936x_(3)-0.132x_(3)^(2)+0.881x_(4)+0.035 x_(4)^(2)-1.048x_(5)+0.009x_(5)^(2)+0.186x_(6)-0.023x_(6)^(2)+0.421x_(7)+6.210×10^(-5)x_(8)-1.051×10-10 x_(8)^(2),决定系数为0.550。结论厦门市恙虫病发病与日最低气温、日平均气温、日最高气温、相对湿度、日降水量及平均气压等气象因素有关,不同气象因素对恙虫病发病影响有所不同。 展开更多
关键词 恙虫病 气象因素 预测模型
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时频电磁技术在黄土塬覆盖区河道砂油藏分布预测中的应用
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作者 于波 王学刚 +2 位作者 李明瑞 张亚东 丁富峰 《石油地球物理勘探》 EI CSCD 北大核心 2024年第3期620-628,共9页
鄂尔多斯盆地西部黄土塬覆盖区的中生界侏罗系油藏成藏主控因素复杂,在未开展三维地震勘探的区域,仅利用二维地震资料进行钻探的成功率较低。为了提高钻井成功率,针对该区侏罗系河道砂油藏特点,采用时频电磁双侧、双源激发、多线接收的... 鄂尔多斯盆地西部黄土塬覆盖区的中生界侏罗系油藏成藏主控因素复杂,在未开展三维地震勘探的区域,仅利用二维地震资料进行钻探的成功率较低。为了提高钻井成功率,针对该区侏罗系河道砂油藏特点,采用时频电磁双侧、双源激发、多线接收的油气检测技术方案。在鄂尔多斯盆地西部ZB地区进行攻关试验,总结了适用于黄土塬覆盖区的时频电磁采集、处理、解释技术方案,即两项针对性采集方案设计和三项针对性处理、解释技术。利用GeoEast软件系统,基于深度学习开展时频电磁多参数智能油气预测。根据时频电磁解释成果,在时频电磁强异常区域部署并完钻Z6井,获得工业油气流,表明时频电磁预测结果与实钻结果吻合,证实了在黄土塬覆盖区利用时频电磁技术对侏罗系薄储层进行油气预测的可靠性。 展开更多
关键词 时频电磁法 黄土塬 薄储层 油气预测 多参数 极化率
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信息视角下数据犯罪的前置化定位及其立法边界
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作者 姚万勤 《政治与法律》 CSSCI 北大核心 2024年第5期49-62,共14页
数据犯罪理论研究混乱的根本原因系理论界难以抛弃“数据与信息概念混同”的路径依赖。以数据为信息的概念混同既不合乎既有法律,亦致使数据犯罪与信息犯罪之间的关系始终不明,在我国尚未建立数据犯罪体系的当下,数据犯罪相关研究也因... 数据犯罪理论研究混乱的根本原因系理论界难以抛弃“数据与信息概念混同”的路径依赖。以数据为信息的概念混同既不合乎既有法律,亦致使数据犯罪与信息犯罪之间的关系始终不明,在我国尚未建立数据犯罪体系的当下,数据犯罪相关研究也因此陷入相对混乱的境地。对此,应从考察数据犯罪的刑法定位着手,摒弃传统充实数据犯罪的法益内涵的研究惯性,转而通过数据与信息的客观属性与立法区分,得出“数据犯罪的刑法定位系信息犯罪的前置化”的逻辑结论。在此前提之下,可以进一步明确数据犯罪的保护法益应是数据的保密性、可用性、完整性,如此也可支撑数据犯罪体系建构的立法边界。具体而言,一方面,在进行相关数据犯罪立法时应考虑以下原则性要求:既将数据犯罪与计算机信息系统犯罪分离,并将其设置为抽象危险犯,又设置专门的刑法条文指引数据犯罪与其他犯罪的罪数判断问题;另一方面,立法新增的数据犯罪也应当控制在一定的范围之内,既要严格控制故意犯罪罪名设置的数量,又要排除处罚过失数据犯罪的行为。 展开更多
关键词 数据犯罪 信息 前置化 数据安全 法益
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