It is of utmost necessity to understand the dynamics of regional active accumulated temperature(AAT)to cope with the negative impacts of global warming on agroforestry development and food security and to provide a re...It is of utmost necessity to understand the dynamics of regional active accumulated temperature(AAT)to cope with the negative impacts of global warming on agroforestry development and food security and to provide a real-time and effective reference basis for regional agroforestry planning.The daily temperature data from 30 meteorological stations in Sichuan Province from 1970 to 2020,and sea surface temperature(SST)index data from the Atlantic Multiphase Oscillation(AMO)and Pacific Decadal Oscillation(PDO)were used for the study.Sichuan Province was divided into the western region(WS)and the eastern region(ES),considering 1000 m above sea level as the boundary.The spatiotemporal characteristics of≥0℃ and≥10℃ active accumulated temperature(AAT0,AAT10)in WS and ES were analyzed comprehensively using 5-day average sliding,empirical orthogonal function(EOF),ensemble empirical mode decomposition(EEMD),and multiple mutation tests.The results show that(1)AAT0 and AAT10 of WS ranged from 3034℃ to 3586℃ and 1971℃ to 2636℃,respectively,while the AAT0 and AAT10 of ES ranged from 5863℃ to 6513℃ and 4847℃ to 5875℃,respectively.The period around 1997 was a significant abrupt change,and the AAT in the province generally increased during the subsequent time period(2)AAT in the study area is mainly driven by the fluctuations of AMO,as reflected by the low-to-high variation of AAT coinciding with the jump of the cold-to-warm phase of AMO.Considering different time scale fluctuations in the past 51 years,the major cycle for both AAT0 and AAT10 in WS is 3.40 a,while the major cycles in ES are 3.64 a and 3.19 a,respectively with a sub-cycle of 7.29 a.AAT fluctuation has an insignificant periodic characteristic of 25.50 a on the interdecadal scale(3)The spatial heterogeneity of AAT in WS is prominent and is mainly reflected by the significantly warm conditions in the south of the WS region and relatively slight warm conditions in the north,as well as by the isolated cooling area in the form of"freezing point",i.e.,Xiaojin county.In contrast,the spatial variability of AAT in ES is more or less consistent,with the warming areas concentrated in the foothills of the western edge of the basin and a slight increase in AAT observed in the central part of the basin.展开更多
This paper sums up the determining analysis of the measuring location of Treflusing a thermocouple during the thermography tests.Laboratory temperature distribution testing methods,analysis of value and location of Tre...This paper sums up the determining analysis of the measuring location of Treflusing a thermocouple during the thermography tests.Laboratory temperature distribution testing methods,analysis of value and location of Treflmeasurement are explained in this paper.The heat source is two halogen lamps of 500 watts eachfitted at a distance of 30–50 cm.Noises appearing during testing of thermography are corrected with measured T_(refl) value.The results of thermogram correction of corroded concrete surfaces using T_(refl) values are displayed in this paper too.The concrete surface temperature results of quantitative image processing method are compared to the experimental test results.The results showed good accuracy,which was seen from most errors<3%and the maximum error is<5%.The end of paper,explained of application Treflvalue to the corroded reinforced concrete thermogram.展开更多
Nonpolar(11–20) a-plane p-type GaN films were successfully grown on r-plane sapphire substrate with the metal–organic chemical vapor deposition(MOCVD) system. The effects of Mg-doping temperature on the structural a...Nonpolar(11–20) a-plane p-type GaN films were successfully grown on r-plane sapphire substrate with the metal–organic chemical vapor deposition(MOCVD) system. The effects of Mg-doping temperature on the structural and electrical properties of nonpolar p-type GaN films were investigated in detail. It is found that all the surface morphology, crystalline quality, strains, and electrical properties of nonpolar a-plane p-type GaN films are interconnected, and are closely related to the Mg-doping temperature. This means that a proper performance of nonpolar p-type GaN can be expected by optimizing the Mg-doping temperature. In fact, a hole concentration of 1.3×10^(18)cm^(-3), a high Mg activation efficiency of 6.5%,an activation energy of 114 me V for Mg acceptor, and a low anisotropy of 8.3% in crystalline quality were achieved with a growth temperature of 990℃. This approach to optimizing the Mg-doping temperature of the nonpolar a-plane p-type GaN film provides an effective way to fabricate high-efficiency optoelectronic devices in the future.展开更多
To study active heat insulation roadway in high temperature mines,the typical high temperature roadway of−965 m in Zhujidong Coal Mine of Anhui,China,is selected as prototype.The ANSYS numerical simulation method is u...To study active heat insulation roadway in high temperature mines,the typical high temperature roadway of−965 m in Zhujidong Coal Mine of Anhui,China,is selected as prototype.The ANSYS numerical simulation method is used for sensitivity analysis of heat insulation layer with different thermal conductivity and thickness,as well as surrounding rock with different thermal conductivity and temperature on a heat-adjusting zone radius,surrounding rock temperature field and wall temperature.The results show that the heat-adjusting zone radius will entirely be in the right power index relationship to the ventilation time.Decrease in thermal conductivity and increase in thickness of insulation layer can effectively reduce the disturbance of airflow on the surrounding rock temperature,hence,beneficial for decreasing wall temperature.This favourable trend significantly decreases with ventilation time,increase in thermal conductivity and temperature of surrounding rock,heat-adjusting zone radius,surrounding rock temperature field,and wall temperature.Sensitivity analysis shows that the thermal physical properties of surrounding rock determine the temperature distribution of the roadway,hence,temperature of surrounding rock is considered as the most sensitive factor of all influencing factors.For the spray layer,thermal conductivity is more sensitive,compared to thickness.It is concluded that increase in the spray layer thickness is not as beneficial as using low thermal conductivity insulation material.Therefore,roadway preferential consideration should be given to the rocks with low temperature and thermal conductivity.The application of the insulation layer has positive significance for the thermal environment control in mine roadway,however,increase in the layer thickness without restriction has a limited effect on the thermal insulation.展开更多
Global warming has become a topic of widespread attention. The climate change will affect the change of agricultural climate resource,thereby affecting the agricultural planting structure,the grain yield,etc. Based on...Global warming has become a topic of widespread attention. The climate change will affect the change of agricultural climate resource,thereby affecting the agricultural planting structure,the grain yield,etc. Based on the daily temperature of Zhangjiakou from 1960 to 2011,the temporal changes of ≥0 ℃ and ≥10 ℃ accumulated temperatures were analyzed by using the methods of linear trend estimation and M-K mutation test. The results indicated that(1) the annual average temperature showed an increasing trend with the linear warming rate of 0. 42 ℃ /10 a in the past 52 years. In 1982,the annual average temperature had abrupt change,especially after 1983,the warming trend increased significantly.(2) In the past 52 years,≥0 ℃ accumulated temperature showed an increasing trend with the warming rate of 89. 4 ℃ /10 a. Mutation point of ≥0 ℃ accumulated temperature appeared in 1983,and after 1985,≥0 ℃ accumulated temperature increased sharply. At the same time,the ≥10 ℃ accumulated temperature had abrupt change in 1983,especially from 1987 to 1995 and after 1986,the warming trend increased sharply.(3) The initial date of ≥0 ℃ presented significant advancing trend,and that of ≥10 ℃ had little change,while their terminal dates presented delaying trend,so the sustained days of ≥0 ℃ and ≥10 ℃ increased significantly.(4) In the past 52 years,the delay of the terminal dates of ≥0 ℃ and ≥10 ℃ was greater than the advancing of the initial dates,and ≥0 ℃ accumulated temperature had a greater increase than ≥10 ℃ accumulated temperature.展开更多
[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang...[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang, the change trends of ≥0 ℃ and ≥10 ℃ accumulated temperature in Shenyang in recent 58 years were analyzed by means of climatic statistics method, and the effects of accumulated temperature variation on agricultural production were discussed. [Result] In recent 58 years, the first day with temperature ≥0 ℃ advanced 10 d, and the last day put off slightly, while sustained days prolonged 13 d, and ≥0 ℃ accumulated temperature increased by 343 ℃·d; meanwhile, the first day with temperature ≥10 ℃ advanced 9 d, and the last day put off 8 d, while sustained days prolonged 16 d, and ≥10 ℃ accumulated temperature increased by 370 ℃·d; compared with the first 20 years, sustained days with temperature ≥0 ℃ and ≥10 ℃ prolonged 9 d in the last 20 years, and ≥0 ℃ and ≥10 ℃ accumulated temperature increased by 196 and 202 ℃·d, respectively. In addition, the increase of heat resources affected agricultural production in Shenyang. [Conclusion] The study could provide theoretical foundation for grasping heat resources variation and adjusting agriculture distribution.展开更多
The objective of this study was to provide reliable basis for decision making for national food security and layout and structure adjustment of grain production in the northeastern China. The data of mean daily air te...The objective of this study was to provide reliable basis for decision making for national food security and layout and structure adjustment of grain production in the northeastern China. The data of mean daily air temperature of 1961-2009 from 106 meteorological stations in the northeastern China were chosen in this study. Using statistical methods and isoline method, the spatio-temporal changes of various decadal ≥ 10℃ accumulated temperature and the climatic means of ≥ 10℃ accumulated temperature were studied in this paper. The results showed that 1) The geo-graphical distribution of ≥ 10℃ accumulated temperature in the northeastern China could be influenced directly by the latitude, longitude and altitude. If latitude moved one degree northward, the average decrease amplitude of the climatic means was 101.9℃ in the study area. 2) The means of decadal ≥ 10℃ accumulated temperature rose since the 1980s, and their increase amplitudes became larger in the 1990s and the 2010s obviously. Compared with those of the 1980s, ≥ 10℃ accumulated temperature increased by about 100℃ in the mountainous and plain areas in the 1990s; compared with those of the 1990s, ≥ 10℃ accumulated temperature increased by about 200℃ in the Hulun Buir High Plain and the Songnen Plain, and 100℃ in the Sanjiang Plain and the Liaohe Plain in the 2010s. 3) The means of the decadal ≥ 10℃ accumulated temperature for 106 meteorological stations in the northeastern China increased with the rate of 145.57℃/10yr in 1961-2009. 4) The climatic means of ≥ 10℃ accumulated temperature increased from 1961-1990 to 1971-2000 and 1981-2009. Compared with the climatic mean of 1971-2000, that of 1981-2009 had increased by above 50℃ in most of the study area, even up to 156℃. Compared with the climatic mean of 1961-1990, that of 1981-2009 increased by above 100℃ in most parts of the study area, even up to 200℃. 5) The maximum northward shift, eastward and westward extension amplitudes of 3100℃, 3300℃ and 3500℃ isolines were larger among all isoli-nes for the climatic means of the three phases. Compared with the positions of the isolines of 1961-1990, those ampli-tudes of 3100℃ isoline of 1981-2009 were 145 km, 109 km and 64 km, respectively; those of 3300℃ isoline were 154 km, 54 km and 64 km, respectively; and the maximum northward shift of 3500℃ isoline was about 100 km.展开更多
In order to understand the occurrence and development of Semanotus bifasciatus(Motschulsky),a borer insect of Platy-cladus orientalis in parts of northern and eastern China and to improve its prediction,the developmen...In order to understand the occurrence and development of Semanotus bifasciatus(Motschulsky),a borer insect of Platy-cladus orientalis in parts of northern and eastern China and to improve its prediction,the developmental threshold temperature(Ct) and effective accumulated temperature(K) of S.bifasciatus were determined under conditions of constant and variable temperatures.The results show that under constant temperatures the value of Ct has a range of 8.90±1.77°C and the value of K lies between 95.19±13.14 degree-day for eggs;the values for larvae are Ct = 13.26±3.06°C and the number of degree-day is K = 2,885.07±187.87 degree-day;for pupae the ranges are Ct = 8.93±2.49°C and K = 131.20±25.63 degree-day.Under the condition of ambient tempera-tures,the values for eggs are Ct = 17.33±1.24°C and K = 70.79±8.99 degree-day.It is suggested that S.bifasciatus adults over-winter in a state of dormancy,not at a diapause.Warm winter may accelerate the life cycle of S.bifasciatus.Equations can be used to predict an early occurrence of S.bifasciatus.展开更多
Since trees and plants can absorb CO2, forests are widely regarded as a carbon sink that may control the amount of CO2 in the atmosphere. The CO2 uptake rate of plants is affected by the plant species and environmenta...Since trees and plants can absorb CO2, forests are widely regarded as a carbon sink that may control the amount of CO2 in the atmosphere. The CO2 uptake rate of plants is affected by the plant species and environmental conditions such as photosynthetically active radiation (PAR), temperature, water and nutrient contents. PAR is the most immediate environmental control on photosynthesis while air temperature affects both photorespiration and dark respiration. In the natural condition, PAR and temperature play an important role in net CO2 uptake. The effects of PAR and air temperature on the CO2 uptake of Pterocarpus macrocarpus grown in a natural habitat were studied in the present work. Due to many uncontrollable factors, a simple rectangular hyperbola could not represent the measured data. The data were divided into groups of 2oC intervals; CO2 uptake in each group may then be related to PAR by a rectangular hyperbola function. Using the obtained functions, the effect of PAR was removed from the original data. The PAR-independent CO2 uptake was then related to air temperature. Finally, the effects of PAR (I) and air temperature (Ta) on the CO2 uptake rate (A) were combined as: (-0.0575Ta2+2.6691Ta-23.264)I A= ——————————————— (-0.00766Ta2+0.40666Ta-3.99924) (-4.8794Ta2+227.13Ta-2456.9)展开更多
Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains p...Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains per panicle and percentage of head-milled rice displayed quadratic curves against the accumulated temperature, and the sterile rate decreased with greater accumulated temperature. However, 1 000-grain weight had no correlation with the accumulated temperature and protein content, amylose content and taste also had no obvious relation with the accumulated temperature. The results from the accumulated temperature differed with rice variety, so the temperature insensitive type variety should be proposed for production.展开更多
High quality nano-sized zirconium carbide(Zr C) powders were successfully fabricated via a developed chemical active dilution self-propagating high-temperature synthesis(SHS) method assisted by ball milling pretreatme...High quality nano-sized zirconium carbide(Zr C) powders were successfully fabricated via a developed chemical active dilution self-propagating high-temperature synthesis(SHS) method assisted by ball milling pretreatment process using traditional cheap zirconium dioxide powder(ZrO2), magnesium powder(Mg) and sucrose(C12H22O11) as raw materials. FSEM, TEM, HRTEM, SAED, XRD, FTIR and Raman, ICPAES, laser particle size analyzer, oxygen and nitrogen analyzer, carbon/sulfur determinator and TG-DSC were employed for the characterization of the morphology, structure, chemical composition and thermal stability of the as-synthesized ZrC samples. The as-synthesized samples demonstrated high purity, low oxygen content and evenly distributed Zr C nano-powders with an average particle size of 50 nm. In addition, the effects of endothermic rate and the possible chemical reaction mechanism were also discussed.展开更多
Accumulated temperature,which is now widely used in agronomy,is an important ecological factor to the growth of plants,but few relative studies have been found on the vegetation area of floodplain grasslands in Poyang...Accumulated temperature,which is now widely used in agronomy,is an important ecological factor to the growth of plants,but few relative studies have been found on the vegetation area of floodplain grasslands in Poyang Lake.This research used the classification and regression tree(CART)to classify normalized vegetation area index derived from MODIS LAI(Moderate Resolution Imaging Spectroradiometer Leaf Area Index)images from 2008 to 2014,according to different climate indexes,such as mean daily air temperature(n),accumulated temperature(jw),daily maximum temperature(g),daily minimum temperature(d),accumulative precipitation(j),water level(s)and average water level for 20 days preceding(a).The results showed that:(1)The accumulated temperature and the 20-day average WL(water level)were found to have the greatest impact on variation in wetland vegetation area,and they both dominated the classification process twice;(2)Two classification thresholds of accumulated temperature were 790°C and 1784°C,approximately corresponding to the beginning of April and midMay;(3)790°C could also be used as a threshold to select remote sensing images to analysis the annual variability of vegetation,i.e.while accumulated temperature is lower than 790°C,remote sensing images of similar accumulated temperature rather than similar date should be selected from different years for comparison.We also found that,effects of different hydrological factors on area of floodplain grasslands showed stage characteristics:(1)From January to March,water level changes slowly with less rainfall,as a result,the 20-day average WL which can interpret the hydrologic characteristics smoothly showed significant importance in this stage;(2)While entering April,intense rainfall make accumulative precipitation to be the dominating factor of classification;(3)From late April to mid-May,in condition of accumulative precipitation higher than 405 mm,daily water level is of most importance,because to the flood recession process as well as rapid water level fluctuations.展开更多
[Objective]The paper was to study the relationship between temperature and development of Potosia brevitarsis Lewis.[Methods]Six constant temperatures(21,24,27,30,33 and 36℃)were set in the laboratory to study develo...[Objective]The paper was to study the relationship between temperature and development of Potosia brevitarsis Lewis.[Methods]Six constant temperatures(21,24,27,30,33 and 36℃)were set in the laboratory to study developmental threshold temperature and effective accumulated temperature of P.brevitarsis.[Result]The developmental durations of various states of P.brevitarsis were shortened with the increasing temperature ranged from 21℃to 36℃;the developmental rates were accelerated with the increasing temperature.The developmental threshold temperatures of egg,larva,pupa and pre-oviposition of adult were estimated to be 12.79,9.15,14.86 and 13.80℃,respectively;the effective accumulated temperature were 136.25,3 031.31,308.92 and 98.35 d·℃,respectively.The developmental threshold temperature and effective accumulated temperature for one complete generation were 9.96℃and 3 628.73 d·℃,respectively.Combined with meteorological data,the theoretical generation number of P.brevitarsis occurred in Shihezi was presumed to be one per year,which was basically coincided with actual occurrence generations in fields.[Conclusion]The paper provided theoretical basis for effective control against P.brevitarsis.展开更多
Light is an essential environmental cue influencing the endogenous circadian clocks that regulate behavioral and physiological processes in animals.Despite extensive research on the circadian rhythms of avian behavior...Light is an essential environmental cue influencing the endogenous circadian clocks that regulate behavioral and physiological processes in animals.Despite extensive research on the circadian rhythms of avian behavior and physiology,the mechanisms by which they adapt and adjust to abnormal photoperiod conditions,such as artificial light,have yet to be fully elucidated.Here,the circadian rhythms of the body mass,activity,and core and peripheral body temperatures of the Eurasian Tree Sparrow(Passer montanus,ETS)-a diurnal passerine-were examined under three different lighting conditions:constant light(LL),constant darkness(DD),and normal light-dark cycles(LD).Our results showed that the activity,body mass,core,tarsometatarsus,and eye temperatures of the ETSs varied significantly with treatment,time,and the interaction between treatment and time;however,there was no significant change in body mass in response to the interaction between time and treatment.Under LD conditions,the ETSs exhibited significant circadian rhythms in activity and core,tarsometatarsus,and eye temperatures.Under LL conditions,only the core temperature exhibited significant rhythmicity.Under DD conditions,there were no significant circadian rhythms in activity,body mass,and eye temperature;however,the core and tarsometatarsus temperatures remained rhythmic.Our results indicate that the core body temperature rhythm of ETS is endogenous and can be maintained under abnormal photoperiods.In contrast,the activity and body surface temperature,uncoupled from the core body temperature under abnormal photoperiod conditions,strongly depend on light.These results differ from those of other diurnal avian species,suggesting a unique coping mechanism of ETS in response to an abnormal photoperiod.展开更多
As an abiotic stress,adverse germination temperatures cause serious disruptions in physiological and biochemical processes involved in seed germination.Using a factorial experiment,we examined the effects of different...As an abiotic stress,adverse germination temperatures cause serious disruptions in physiological and biochemical processes involved in seed germination.Using a factorial experiment,we examined the effects of different seed priming treatments on enzymatic and biochemical performances of rice seed germination under different temperatures.Each of the rice genotypes(Hashemi,Sadry-domsefid,IRON-70-7053-7 and NORIN-22)was primed with hydro-hardening,KCl,CaCl2 and ascorbic acid(AsA)and without a priming agent as a control at low(15℃),optimum(25℃)and high(35℃)germination temperatures.The results showed that the enzymatic and biochemical performances of all the rice genotypes were affected by the seed priming agents,especially under the low germination temperature.At 15℃,seed priming with AsA was found to be the best agent for the activities of amylase,α-amylase,catalase(CAT),peroxidase(POX),ascorbate peroxidase(APOX)and superoxide dismutase(SOD)as well as the content of soluble sugars in the NORIN-22 genotype,and for protease activity and soluble protein content in the IRON-70-7053-7 genotype.SOD at the low germination temperature and CAT,POX and protease at the optimum and high germination temperatures were the most important enzymes in occurrence of germination potential in terms of seedling length,vigor index,normal seedling rate and germination rate.Under the priming agents,the highest changes in normal seedling rate were observed at the low and optimum germination temperatures by AsA priming in the Hashemi and NORIN-22 genotypes,and at the high germination temperature under KCl priming in the Hashemi genotype.展开更多
Hibiscus rosa-sinensis, Rosa sp. (miniature roses), Sinningia speciosa, Gerbera hybrida, Kalanchoe blossfeldiana, Hydrangea, Begonia x hiemalis, Calceolaria, Cyclamen persicum and Pelargonium domesticum were grown at ...Hibiscus rosa-sinensis, Rosa sp. (miniature roses), Sinningia speciosa, Gerbera hybrida, Kalanchoe blossfeldiana, Hydrangea, Begonia x hiemalis, Calceolaria, Cyclamen persicum and Pelargonium domesticum were grown at six photon flux densities (85, 130, 170, 215, 255 and 300 μmol·m-2·s-1, PFD) during lighting periods of 20 h·day-1 at three air temperatures (18°C, 21°C and 24°C) in midwinter at latitude 59° north. This corresponded to photosynthetic active radiations (PAR) ranging from 6.1 to 21.6 mol·m-2·day-1. Time until flowering decreased in all species except Cyclamen when the temperature increased from 18°C to 21°C, particularly at lower PFD levels. A further increase in temperature, from 21°C to 24°C, clearly decreased time until flowering in six of the ten tested species. Generally, this represented a reduction in the time until flowering between 20% and 40%. The dry weight of the plants at time of flowering increased up to 170 μmol·m-2·s-1 PFD (12.2 mol·m-2·day-1 PAR) in Hibiscus, miniature rose, Kalanchoe and Pelargonium, while the dry weight reached a maximum at 85 to 130 μmol·m-2·s-1 PFD mol·m-2·day-1 (6.1 to 9.4 mol·m-2·day-1)in the other species. Based on the present results a PAR level of 6 to 8 mol m-2·day-1 is recommended for Calceolaria and Cyclamen, of 8 to 10 mol·m-2·day-1 for Sinningia, Gerbera, Kalanchoe, Hydrangea and Begonia, of 10 to 12 mol·m-2·day-1 for Pelargonium and of 12 to 15 mol·m-2 day-1 for Hibiscus and miniature roses.展开更多
[Objectives]To explore the effects of different sterilization conditions on nutrition and flavor of apple vinegar.[Methods]Five kinds of high temperature short time(HTST)sterilization conditions were selected to treat...[Objectives]To explore the effects of different sterilization conditions on nutrition and flavor of apple vinegar.[Methods]Five kinds of high temperature short time(HTST)sterilization conditions were selected to treat apple vinegar,and the volatile aroma components and the content of active components in apple vinegar before and after sterilization were analyzed.[Results]Compared with the control,the contents of total acid and malic acid in the samples after sterilization changed little,but the contents of citric acid increased significantly(P<0.01),and the contents of total phenols,ascorbic acid and total flavonoids decreased.Ethyl acetate,isopentyl acetate,ethyl caprylate,phenethyl acetate,1-pentanol,phenylethyl alcohol,acetic acid,and sec-butyl ether were the characteristic aroma components which contributed to the flavor of apple vinegar.As sterilization temperature increased,the content of esters decreased,while the content of acids,alcohols and aldehydes increased.The contents of nutrition,active components and volatile aroma components in apple vinegar under 100℃and 30 s sterilization conditions had little change compared with other sterilization conditions,so 100℃and 30 s were the optimal sterilization conditions.[Conclusions]Under different sterilization conditions,the content of flavor components in apple vinegar will change greatly,which will affect the quality of apple vinegar.展开更多
This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eig...This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eigenvectors of the solar background magnetic field (SBMF) and with changes of Sun-Earth distances caused by solar inertial motion resulting from the gravitation of large planets in the solar system. Using the wavelet analysis of the GLB and HadCRUTS datasets two periods: 21.4 and 36 years in GLB, set and the period of about 19.6 years in the HadCRUTS are discovered. The 21.4-year period is associated with variations in solar activity defined by the summary curve of the largest eigenvectors of the SBMF. A dominant 21.4-year period is also reported in the variations of the sea level, which is linked with the period of 21.4 years detected in the GLB temperature and the summary curve of the SBMF variations. The wavelet analysis of ice and snow areas shows that in the Southern hemisphere, it does not show any links to solar activity periods while in the Northern hemisphere, the ice area reveals a period of 10.7 years equal to a usual solar activity cycle. The TSI in March-August of every year is found to grow with every year following closely the temperature curve, because the Sun moves closer to the Earth orbit owing to gravitation of large planets (solar inertial motion, SIM), while the variations of solar radiation during a whole year have more steady distribution without a sharp TSI increase during the last two centuries. The additional TSI contribution caused by SIM is likely to secure the additional energy input and exchange between the ocean and atmosphere.展开更多
A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temp...A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temperature and dissolved oxygen(DO) on cold active lipase production by batch culture of metagenomic library recombinant clone(CAPL3) from deep-sea sediment were investigated. First, a two-stage temperature control strategy was developed, in which the temperature was kept at 34 °C for the first 15 h, and then switched to30 °C. The cold active lipase activity and productivity reached 315.2 U·ml^(-1)and 8.08 U·ml^(-1)·h^(-1), respectively,increased by both 14.5% compared to the results obtained with temperature controlled at 30°C. In addition, different DO control modes were conducted, based on the data obtained from the different DO control strategies and analysis of kinetics parameters at different DO levels. A step-wise temperature and DO control strategy were developed to improve lipase production, i.e., temperature and DO level were controlled at 34 °C, 30% during 0–15 h;30 °C, 30% during 15–18 h, and 30 °C, 20% during 18–39 h. With this strategy, the maximum lipase activity reached 354.6 U·ml^(-1)at 39 h, which was 28.8% higher than that achieved without temperature and DO control(275.3 U·ml^(-1)).展开更多
The aim of this study was to investigate changes of polyphenols content and the antioxidant activity of mulberry fruit powder after heating at high temperature.The mulberry fruit powder was heated by baking method at ...The aim of this study was to investigate changes of polyphenols content and the antioxidant activity of mulberry fruit powder after heating at high temperature.The mulberry fruit powder was heated by baking method at different temperature and time.The DPPH scavenging ability,the OH^(•-) scavenging ability and the O_(2)^(•-) scavenging ability were used to evaluate the changes in the antioxidant activity of the mulberry fruit powder after the heat treatment.The results showed that 74.87%of the polyphenols in the mulberry powder were lost after heating at 150℃for 5 min,and almost all the polyphenols were lost with the increase of the heating time and temperature.The antioxidant experiment showed that the DPPH scavenging rate,OH^(•-) scavenging rate and O_(2)^(•-) scavenging rate of mulberry fruit powder were 68.90%,39.15%and 14.09%,respectively after treatment at 150℃ for 5 min.Mulberry fruit powder still has some potential to be added to baked goods as a functional ingredient.展开更多
基金the National Natural Science Foundation of China(Grant No.51779114)。
文摘It is of utmost necessity to understand the dynamics of regional active accumulated temperature(AAT)to cope with the negative impacts of global warming on agroforestry development and food security and to provide a real-time and effective reference basis for regional agroforestry planning.The daily temperature data from 30 meteorological stations in Sichuan Province from 1970 to 2020,and sea surface temperature(SST)index data from the Atlantic Multiphase Oscillation(AMO)and Pacific Decadal Oscillation(PDO)were used for the study.Sichuan Province was divided into the western region(WS)and the eastern region(ES),considering 1000 m above sea level as the boundary.The spatiotemporal characteristics of≥0℃ and≥10℃ active accumulated temperature(AAT0,AAT10)in WS and ES were analyzed comprehensively using 5-day average sliding,empirical orthogonal function(EOF),ensemble empirical mode decomposition(EEMD),and multiple mutation tests.The results show that(1)AAT0 and AAT10 of WS ranged from 3034℃ to 3586℃ and 1971℃ to 2636℃,respectively,while the AAT0 and AAT10 of ES ranged from 5863℃ to 6513℃ and 4847℃ to 5875℃,respectively.The period around 1997 was a significant abrupt change,and the AAT in the province generally increased during the subsequent time period(2)AAT in the study area is mainly driven by the fluctuations of AMO,as reflected by the low-to-high variation of AAT coinciding with the jump of the cold-to-warm phase of AMO.Considering different time scale fluctuations in the past 51 years,the major cycle for both AAT0 and AAT10 in WS is 3.40 a,while the major cycles in ES are 3.64 a and 3.19 a,respectively with a sub-cycle of 7.29 a.AAT fluctuation has an insignificant periodic characteristic of 25.50 a on the interdecadal scale(3)The spatial heterogeneity of AAT in WS is prominent and is mainly reflected by the significantly warm conditions in the south of the WS region and relatively slight warm conditions in the north,as well as by the isolated cooling area in the form of"freezing point",i.e.,Xiaojin county.In contrast,the spatial variability of AAT in ES is more or less consistent,with the warming areas concentrated in the foothills of the western edge of the basin and a slight increase in AAT observed in the central part of the basin.
基金This research was supported by the P3MI Research Grants.Thanks to Prof.Herlien D Setio as authors who received the grant.
文摘This paper sums up the determining analysis of the measuring location of Treflusing a thermocouple during the thermography tests.Laboratory temperature distribution testing methods,analysis of value and location of Treflmeasurement are explained in this paper.The heat source is two halogen lamps of 500 watts eachfitted at a distance of 30–50 cm.Noises appearing during testing of thermography are corrected with measured T_(refl) value.The results of thermogram correction of corroded concrete surfaces using T_(refl) values are displayed in this paper too.The concrete surface temperature results of quantitative image processing method are compared to the experimental test results.The results showed good accuracy,which was seen from most errors<3%and the maximum error is<5%.The end of paper,explained of application Treflvalue to the corroded reinforced concrete thermogram.
基金Project supported by the National Key Research and Development Program of China (Grant Nos.2021YFB3601000 and 2021YFB3601002)the National Natural Science Foundation of China (Grant Nos.62074077,61921005,61974062,62204121,and 61904082)+1 种基金Leading-edge Technology Program of Jiangsu Natural Science Foundation (Grant No.BE2021008-2)the China Postdoctoral Science Foundation (Grant No.2020M671441)。
文摘Nonpolar(11–20) a-plane p-type GaN films were successfully grown on r-plane sapphire substrate with the metal–organic chemical vapor deposition(MOCVD) system. The effects of Mg-doping temperature on the structural and electrical properties of nonpolar p-type GaN films were investigated in detail. It is found that all the surface morphology, crystalline quality, strains, and electrical properties of nonpolar a-plane p-type GaN films are interconnected, and are closely related to the Mg-doping temperature. This means that a proper performance of nonpolar p-type GaN can be expected by optimizing the Mg-doping temperature. In fact, a hole concentration of 1.3×10^(18)cm^(-3), a high Mg activation efficiency of 6.5%,an activation energy of 114 me V for Mg acceptor, and a low anisotropy of 8.3% in crystalline quality were achieved with a growth temperature of 990℃. This approach to optimizing the Mg-doping temperature of the nonpolar a-plane p-type GaN film provides an effective way to fabricate high-efficiency optoelectronic devices in the future.
基金This work was supported by the National Natural Science Foundation of China(51774011)Funding Project of Anhui University of Science and Technology(QN2019115)Introduced Research Funding of Anhui University of Science and Technology(13190022).
文摘To study active heat insulation roadway in high temperature mines,the typical high temperature roadway of−965 m in Zhujidong Coal Mine of Anhui,China,is selected as prototype.The ANSYS numerical simulation method is used for sensitivity analysis of heat insulation layer with different thermal conductivity and thickness,as well as surrounding rock with different thermal conductivity and temperature on a heat-adjusting zone radius,surrounding rock temperature field and wall temperature.The results show that the heat-adjusting zone radius will entirely be in the right power index relationship to the ventilation time.Decrease in thermal conductivity and increase in thickness of insulation layer can effectively reduce the disturbance of airflow on the surrounding rock temperature,hence,beneficial for decreasing wall temperature.This favourable trend significantly decreases with ventilation time,increase in thermal conductivity and temperature of surrounding rock,heat-adjusting zone radius,surrounding rock temperature field,and wall temperature.Sensitivity analysis shows that the thermal physical properties of surrounding rock determine the temperature distribution of the roadway,hence,temperature of surrounding rock is considered as the most sensitive factor of all influencing factors.For the spray layer,thermal conductivity is more sensitive,compared to thickness.It is concluded that increase in the spray layer thickness is not as beneficial as using low thermal conductivity insulation material.Therefore,roadway preferential consideration should be given to the rocks with low temperature and thermal conductivity.The application of the insulation layer has positive significance for the thermal environment control in mine roadway,however,increase in the layer thickness without restriction has a limited effect on the thermal insulation.
文摘Global warming has become a topic of widespread attention. The climate change will affect the change of agricultural climate resource,thereby affecting the agricultural planting structure,the grain yield,etc. Based on the daily temperature of Zhangjiakou from 1960 to 2011,the temporal changes of ≥0 ℃ and ≥10 ℃ accumulated temperatures were analyzed by using the methods of linear trend estimation and M-K mutation test. The results indicated that(1) the annual average temperature showed an increasing trend with the linear warming rate of 0. 42 ℃ /10 a in the past 52 years. In 1982,the annual average temperature had abrupt change,especially after 1983,the warming trend increased significantly.(2) In the past 52 years,≥0 ℃ accumulated temperature showed an increasing trend with the warming rate of 89. 4 ℃ /10 a. Mutation point of ≥0 ℃ accumulated temperature appeared in 1983,and after 1985,≥0 ℃ accumulated temperature increased sharply. At the same time,the ≥10 ℃ accumulated temperature had abrupt change in 1983,especially from 1987 to 1995 and after 1986,the warming trend increased sharply.(3) The initial date of ≥0 ℃ presented significant advancing trend,and that of ≥10 ℃ had little change,while their terminal dates presented delaying trend,so the sustained days of ≥0 ℃ and ≥10 ℃ increased significantly.(4) In the past 52 years,the delay of the terminal dates of ≥0 ℃ and ≥10 ℃ was greater than the advancing of the initial dates,and ≥0 ℃ accumulated temperature had a greater increase than ≥10 ℃ accumulated temperature.
基金Supported by Scientific Research Project of Shenyang Science and Technology Bureau([2010]Number 15)
文摘[Objective] The aim was to study the change trend of accumulated temperature in Shenyang in recent 58 years, as well as its effect on agricultural production. [Method] Based on the surface temperature data in Shenyang, the change trends of ≥0 ℃ and ≥10 ℃ accumulated temperature in Shenyang in recent 58 years were analyzed by means of climatic statistics method, and the effects of accumulated temperature variation on agricultural production were discussed. [Result] In recent 58 years, the first day with temperature ≥0 ℃ advanced 10 d, and the last day put off slightly, while sustained days prolonged 13 d, and ≥0 ℃ accumulated temperature increased by 343 ℃·d; meanwhile, the first day with temperature ≥10 ℃ advanced 9 d, and the last day put off 8 d, while sustained days prolonged 16 d, and ≥10 ℃ accumulated temperature increased by 370 ℃·d; compared with the first 20 years, sustained days with temperature ≥0 ℃ and ≥10 ℃ prolonged 9 d in the last 20 years, and ≥0 ℃ and ≥10 ℃ accumulated temperature increased by 196 and 202 ℃·d, respectively. In addition, the increase of heat resources affected agricultural production in Shenyang. [Conclusion] The study could provide theoretical foundation for grasping heat resources variation and adjusting agriculture distribution.
基金Under the auspices of National Natural Science Foundation of China (No. 40771190)Special Fund for Meteorological Scientific Research in the Public Interest (No. GYHY200706030)
文摘The objective of this study was to provide reliable basis for decision making for national food security and layout and structure adjustment of grain production in the northeastern China. The data of mean daily air temperature of 1961-2009 from 106 meteorological stations in the northeastern China were chosen in this study. Using statistical methods and isoline method, the spatio-temporal changes of various decadal ≥ 10℃ accumulated temperature and the climatic means of ≥ 10℃ accumulated temperature were studied in this paper. The results showed that 1) The geo-graphical distribution of ≥ 10℃ accumulated temperature in the northeastern China could be influenced directly by the latitude, longitude and altitude. If latitude moved one degree northward, the average decrease amplitude of the climatic means was 101.9℃ in the study area. 2) The means of decadal ≥ 10℃ accumulated temperature rose since the 1980s, and their increase amplitudes became larger in the 1990s and the 2010s obviously. Compared with those of the 1980s, ≥ 10℃ accumulated temperature increased by about 100℃ in the mountainous and plain areas in the 1990s; compared with those of the 1990s, ≥ 10℃ accumulated temperature increased by about 200℃ in the Hulun Buir High Plain and the Songnen Plain, and 100℃ in the Sanjiang Plain and the Liaohe Plain in the 2010s. 3) The means of the decadal ≥ 10℃ accumulated temperature for 106 meteorological stations in the northeastern China increased with the rate of 145.57℃/10yr in 1961-2009. 4) The climatic means of ≥ 10℃ accumulated temperature increased from 1961-1990 to 1971-2000 and 1981-2009. Compared with the climatic mean of 1971-2000, that of 1981-2009 had increased by above 50℃ in most of the study area, even up to 156℃. Compared with the climatic mean of 1961-1990, that of 1981-2009 increased by above 100℃ in most parts of the study area, even up to 200℃. 5) The maximum northward shift, eastward and westward extension amplitudes of 3100℃, 3300℃ and 3500℃ isolines were larger among all isoli-nes for the climatic means of the three phases. Compared with the positions of the isolines of 1961-1990, those ampli-tudes of 3100℃ isoline of 1981-2009 were 145 km, 109 km and 64 km, respectively; those of 3300℃ isoline were 154 km, 54 km and 64 km, respectively; and the maximum northward shift of 3500℃ isoline was about 100 km.
文摘In order to understand the occurrence and development of Semanotus bifasciatus(Motschulsky),a borer insect of Platy-cladus orientalis in parts of northern and eastern China and to improve its prediction,the developmental threshold temperature(Ct) and effective accumulated temperature(K) of S.bifasciatus were determined under conditions of constant and variable temperatures.The results show that under constant temperatures the value of Ct has a range of 8.90±1.77°C and the value of K lies between 95.19±13.14 degree-day for eggs;the values for larvae are Ct = 13.26±3.06°C and the number of degree-day is K = 2,885.07±187.87 degree-day;for pupae the ranges are Ct = 8.93±2.49°C and K = 131.20±25.63 degree-day.Under the condition of ambient tempera-tures,the values for eggs are Ct = 17.33±1.24°C and K = 70.79±8.99 degree-day.It is suggested that S.bifasciatus adults over-winter in a state of dormancy,not at a diapause.Warm winter may accelerate the life cycle of S.bifasciatus.Equations can be used to predict an early occurrence of S.bifasciatus.
文摘Since trees and plants can absorb CO2, forests are widely regarded as a carbon sink that may control the amount of CO2 in the atmosphere. The CO2 uptake rate of plants is affected by the plant species and environmental conditions such as photosynthetically active radiation (PAR), temperature, water and nutrient contents. PAR is the most immediate environmental control on photosynthesis while air temperature affects both photorespiration and dark respiration. In the natural condition, PAR and temperature play an important role in net CO2 uptake. The effects of PAR and air temperature on the CO2 uptake of Pterocarpus macrocarpus grown in a natural habitat were studied in the present work. Due to many uncontrollable factors, a simple rectangular hyperbola could not represent the measured data. The data were divided into groups of 2oC intervals; CO2 uptake in each group may then be related to PAR by a rectangular hyperbola function. Using the obtained functions, the effect of PAR was removed from the original data. The PAR-independent CO2 uptake was then related to air temperature. Finally, the effects of PAR (I) and air temperature (Ta) on the CO2 uptake rate (A) were combined as: (-0.0575Ta2+2.6691Ta-23.264)I A= ——————————————— (-0.00766Ta2+0.40666Ta-3.99924) (-4.8794Ta2+227.13Ta-2456.9)
基金Supported by the Public Industry Project of Ministry of Agriculture(201303126)Postdoctoral Fund of Heilongjiang Province(LBH-Z13189)Innovation Project of Institute(2012ZD013)
文摘Five rice varieties were planted to determine the variation of the yield and quality traits in five different regions in a cold area of China. The results showed that the number of the panicles, the number of grains per panicle and percentage of head-milled rice displayed quadratic curves against the accumulated temperature, and the sterile rate decreased with greater accumulated temperature. However, 1 000-grain weight had no correlation with the accumulated temperature and protein content, amylose content and taste also had no obvious relation with the accumulated temperature. The results from the accumulated temperature differed with rice variety, so the temperature insensitive type variety should be proposed for production.
基金Funded by the Program for New Century Excellent Talents in University(No.NCET-12-0655)the Guangxi Natural Science Foundation(No.2014GXNSFFA118004)the Self-determined and Innovative Research Funds of WUT(Nos.136643002 and No.2013IV058)
文摘High quality nano-sized zirconium carbide(Zr C) powders were successfully fabricated via a developed chemical active dilution self-propagating high-temperature synthesis(SHS) method assisted by ball milling pretreatment process using traditional cheap zirconium dioxide powder(ZrO2), magnesium powder(Mg) and sucrose(C12H22O11) as raw materials. FSEM, TEM, HRTEM, SAED, XRD, FTIR and Raman, ICPAES, laser particle size analyzer, oxygen and nitrogen analyzer, carbon/sulfur determinator and TG-DSC were employed for the characterization of the morphology, structure, chemical composition and thermal stability of the as-synthesized ZrC samples. The as-synthesized samples demonstrated high purity, low oxygen content and evenly distributed Zr C nano-powders with an average particle size of 50 nm. In addition, the effects of endothermic rate and the possible chemical reaction mechanism were also discussed.
基金This work was supported by the National Natural Science Foundation of China“Study on the dynamic mechanism of grassland ecosystem response to climate change in Qinghai Plateau”under grant number U20A2098the Second Tibet Plateau Scientific Expedition and Research Program(STEP)under grant number 2019QZKK0804.
文摘Accumulated temperature,which is now widely used in agronomy,is an important ecological factor to the growth of plants,but few relative studies have been found on the vegetation area of floodplain grasslands in Poyang Lake.This research used the classification and regression tree(CART)to classify normalized vegetation area index derived from MODIS LAI(Moderate Resolution Imaging Spectroradiometer Leaf Area Index)images from 2008 to 2014,according to different climate indexes,such as mean daily air temperature(n),accumulated temperature(jw),daily maximum temperature(g),daily minimum temperature(d),accumulative precipitation(j),water level(s)and average water level for 20 days preceding(a).The results showed that:(1)The accumulated temperature and the 20-day average WL(water level)were found to have the greatest impact on variation in wetland vegetation area,and they both dominated the classification process twice;(2)Two classification thresholds of accumulated temperature were 790°C and 1784°C,approximately corresponding to the beginning of April and midMay;(3)790°C could also be used as a threshold to select remote sensing images to analysis the annual variability of vegetation,i.e.while accumulated temperature is lower than 790°C,remote sensing images of similar accumulated temperature rather than similar date should be selected from different years for comparison.We also found that,effects of different hydrological factors on area of floodplain grasslands showed stage characteristics:(1)From January to March,water level changes slowly with less rainfall,as a result,the 20-day average WL which can interpret the hydrologic characteristics smoothly showed significant importance in this stage;(2)While entering April,intense rainfall make accumulative precipitation to be the dominating factor of classification;(3)From late April to mid-May,in condition of accumulative precipitation higher than 405 mm,daily water level is of most importance,because to the flood recession process as well as rapid water level fluctuations.
基金Supported by National Natural Science Foundation of China(31360452)&National Natural Science Foundation of China(41161068)Guide Project of Xinjiang Academy of Agricultural and Reclamation Science(YYD2009-3)
文摘[Objective]The paper was to study the relationship between temperature and development of Potosia brevitarsis Lewis.[Methods]Six constant temperatures(21,24,27,30,33 and 36℃)were set in the laboratory to study developmental threshold temperature and effective accumulated temperature of P.brevitarsis.[Result]The developmental durations of various states of P.brevitarsis were shortened with the increasing temperature ranged from 21℃to 36℃;the developmental rates were accelerated with the increasing temperature.The developmental threshold temperatures of egg,larva,pupa and pre-oviposition of adult were estimated to be 12.79,9.15,14.86 and 13.80℃,respectively;the effective accumulated temperature were 136.25,3 031.31,308.92 and 98.35 d·℃,respectively.The developmental threshold temperature and effective accumulated temperature for one complete generation were 9.96℃and 3 628.73 d·℃,respectively.Combined with meteorological data,the theoretical generation number of P.brevitarsis occurred in Shihezi was presumed to be one per year,which was basically coincided with actual occurrence generations in fields.[Conclusion]The paper provided theoretical basis for effective control against P.brevitarsis.
基金the National Natural Science Foundation of China(NSFC,31971413)the Natural Science Foundation of Hebei Province(C2020205038)to Dongming Li.
文摘Light is an essential environmental cue influencing the endogenous circadian clocks that regulate behavioral and physiological processes in animals.Despite extensive research on the circadian rhythms of avian behavior and physiology,the mechanisms by which they adapt and adjust to abnormal photoperiod conditions,such as artificial light,have yet to be fully elucidated.Here,the circadian rhythms of the body mass,activity,and core and peripheral body temperatures of the Eurasian Tree Sparrow(Passer montanus,ETS)-a diurnal passerine-were examined under three different lighting conditions:constant light(LL),constant darkness(DD),and normal light-dark cycles(LD).Our results showed that the activity,body mass,core,tarsometatarsus,and eye temperatures of the ETSs varied significantly with treatment,time,and the interaction between treatment and time;however,there was no significant change in body mass in response to the interaction between time and treatment.Under LD conditions,the ETSs exhibited significant circadian rhythms in activity and core,tarsometatarsus,and eye temperatures.Under LL conditions,only the core temperature exhibited significant rhythmicity.Under DD conditions,there were no significant circadian rhythms in activity,body mass,and eye temperature;however,the core and tarsometatarsus temperatures remained rhythmic.Our results indicate that the core body temperature rhythm of ETS is endogenous and can be maintained under abnormal photoperiods.In contrast,the activity and body surface temperature,uncoupled from the core body temperature under abnormal photoperiod conditions,strongly depend on light.These results differ from those of other diurnal avian species,suggesting a unique coping mechanism of ETS in response to an abnormal photoperiod.
基金supported by the Gorgan University of Agricultural Sciences and Natural ResourcesSabz Fanavaran Loozan Shomal Company+1 种基金University of GuilanGuilan Science and Technology Park, Iran
文摘As an abiotic stress,adverse germination temperatures cause serious disruptions in physiological and biochemical processes involved in seed germination.Using a factorial experiment,we examined the effects of different seed priming treatments on enzymatic and biochemical performances of rice seed germination under different temperatures.Each of the rice genotypes(Hashemi,Sadry-domsefid,IRON-70-7053-7 and NORIN-22)was primed with hydro-hardening,KCl,CaCl2 and ascorbic acid(AsA)and without a priming agent as a control at low(15℃),optimum(25℃)and high(35℃)germination temperatures.The results showed that the enzymatic and biochemical performances of all the rice genotypes were affected by the seed priming agents,especially under the low germination temperature.At 15℃,seed priming with AsA was found to be the best agent for the activities of amylase,α-amylase,catalase(CAT),peroxidase(POX),ascorbate peroxidase(APOX)and superoxide dismutase(SOD)as well as the content of soluble sugars in the NORIN-22 genotype,and for protease activity and soluble protein content in the IRON-70-7053-7 genotype.SOD at the low germination temperature and CAT,POX and protease at the optimum and high germination temperatures were the most important enzymes in occurrence of germination potential in terms of seedling length,vigor index,normal seedling rate and germination rate.Under the priming agents,the highest changes in normal seedling rate were observed at the low and optimum germination temperatures by AsA priming in the Hashemi and NORIN-22 genotypes,and at the high germination temperature under KCl priming in the Hashemi genotype.
基金funded by the Norwegian Research Council and the Norwegian Growers Association
文摘Hibiscus rosa-sinensis, Rosa sp. (miniature roses), Sinningia speciosa, Gerbera hybrida, Kalanchoe blossfeldiana, Hydrangea, Begonia x hiemalis, Calceolaria, Cyclamen persicum and Pelargonium domesticum were grown at six photon flux densities (85, 130, 170, 215, 255 and 300 μmol·m-2·s-1, PFD) during lighting periods of 20 h·day-1 at three air temperatures (18°C, 21°C and 24°C) in midwinter at latitude 59° north. This corresponded to photosynthetic active radiations (PAR) ranging from 6.1 to 21.6 mol·m-2·day-1. Time until flowering decreased in all species except Cyclamen when the temperature increased from 18°C to 21°C, particularly at lower PFD levels. A further increase in temperature, from 21°C to 24°C, clearly decreased time until flowering in six of the ten tested species. Generally, this represented a reduction in the time until flowering between 20% and 40%. The dry weight of the plants at time of flowering increased up to 170 μmol·m-2·s-1 PFD (12.2 mol·m-2·day-1 PAR) in Hibiscus, miniature rose, Kalanchoe and Pelargonium, while the dry weight reached a maximum at 85 to 130 μmol·m-2·s-1 PFD mol·m-2·day-1 (6.1 to 9.4 mol·m-2·day-1)in the other species. Based on the present results a PAR level of 6 to 8 mol m-2·day-1 is recommended for Calceolaria and Cyclamen, of 8 to 10 mol·m-2·day-1 for Sinningia, Gerbera, Kalanchoe, Hydrangea and Begonia, of 10 to 12 mol·m-2·day-1 for Pelargonium and of 12 to 15 mol·m-2 day-1 for Hibiscus and miniature roses.
基金Supported by Taishan Industrial Leading Talent Project (Efficient Ecological Agriculture Innovation) (LJNY202001)Science and Technology R&D Project of Longkou City in Shandong Province (2021KJJH028)Science and Technology Small and Medium-sized Enterprises Innovation Capability Improvement Project in Shandong Province (2023 TS GC0906).
文摘[Objectives]To explore the effects of different sterilization conditions on nutrition and flavor of apple vinegar.[Methods]Five kinds of high temperature short time(HTST)sterilization conditions were selected to treat apple vinegar,and the volatile aroma components and the content of active components in apple vinegar before and after sterilization were analyzed.[Results]Compared with the control,the contents of total acid and malic acid in the samples after sterilization changed little,but the contents of citric acid increased significantly(P<0.01),and the contents of total phenols,ascorbic acid and total flavonoids decreased.Ethyl acetate,isopentyl acetate,ethyl caprylate,phenethyl acetate,1-pentanol,phenylethyl alcohol,acetic acid,and sec-butyl ether were the characteristic aroma components which contributed to the flavor of apple vinegar.As sterilization temperature increased,the content of esters decreased,while the content of acids,alcohols and aldehydes increased.The contents of nutrition,active components and volatile aroma components in apple vinegar under 100℃and 30 s sterilization conditions had little change compared with other sterilization conditions,so 100℃and 30 s were the optimal sterilization conditions.[Conclusions]Under different sterilization conditions,the content of flavor components in apple vinegar will change greatly,which will affect the quality of apple vinegar.
文摘This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eigenvectors of the solar background magnetic field (SBMF) and with changes of Sun-Earth distances caused by solar inertial motion resulting from the gravitation of large planets in the solar system. Using the wavelet analysis of the GLB and HadCRUTS datasets two periods: 21.4 and 36 years in GLB, set and the period of about 19.6 years in the HadCRUTS are discovered. The 21.4-year period is associated with variations in solar activity defined by the summary curve of the largest eigenvectors of the SBMF. A dominant 21.4-year period is also reported in the variations of the sea level, which is linked with the period of 21.4 years detected in the GLB temperature and the summary curve of the SBMF variations. The wavelet analysis of ice and snow areas shows that in the Southern hemisphere, it does not show any links to solar activity periods while in the Northern hemisphere, the ice area reveals a period of 10.7 years equal to a usual solar activity cycle. The TSI in March-August of every year is found to grow with every year following closely the temperature curve, because the Sun moves closer to the Earth orbit owing to gravitation of large planets (solar inertial motion, SIM), while the variations of solar radiation during a whole year have more steady distribution without a sharp TSI increase during the last two centuries. The additional TSI contribution caused by SIM is likely to secure the additional energy input and exchange between the ocean and atmosphere.
基金Supported by the Hi-Tech Research and Development Program of China(863 program of China2012AA092103)China Ocean Mineral Resources R&D Association(DY125-15-T-06)
文摘A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temperature and dissolved oxygen(DO) on cold active lipase production by batch culture of metagenomic library recombinant clone(CAPL3) from deep-sea sediment were investigated. First, a two-stage temperature control strategy was developed, in which the temperature was kept at 34 °C for the first 15 h, and then switched to30 °C. The cold active lipase activity and productivity reached 315.2 U·ml^(-1)and 8.08 U·ml^(-1)·h^(-1), respectively,increased by both 14.5% compared to the results obtained with temperature controlled at 30°C. In addition, different DO control modes were conducted, based on the data obtained from the different DO control strategies and analysis of kinetics parameters at different DO levels. A step-wise temperature and DO control strategy were developed to improve lipase production, i.e., temperature and DO level were controlled at 34 °C, 30% during 0–15 h;30 °C, 30% during 15–18 h, and 30 °C, 20% during 18–39 h. With this strategy, the maximum lipase activity reached 354.6 U·ml^(-1)at 39 h, which was 28.8% higher than that achieved without temperature and DO control(275.3 U·ml^(-1)).
基金This project is funded by the Livelihood Plan Project of Department of Science and Technology of Liaoning Province(2021JH2/10300069,2019-ZD-0845)Department of Education of Liaoning Province(LJKZ0918)National College Students’Innovation and Entrepreneurship Training Program(202210163013).
文摘The aim of this study was to investigate changes of polyphenols content and the antioxidant activity of mulberry fruit powder after heating at high temperature.The mulberry fruit powder was heated by baking method at different temperature and time.The DPPH scavenging ability,the OH^(•-) scavenging ability and the O_(2)^(•-) scavenging ability were used to evaluate the changes in the antioxidant activity of the mulberry fruit powder after the heat treatment.The results showed that 74.87%of the polyphenols in the mulberry powder were lost after heating at 150℃for 5 min,and almost all the polyphenols were lost with the increase of the heating time and temperature.The antioxidant experiment showed that the DPPH scavenging rate,OH^(•-) scavenging rate and O_(2)^(•-) scavenging rate of mulberry fruit powder were 68.90%,39.15%and 14.09%,respectively after treatment at 150℃ for 5 min.Mulberry fruit powder still has some potential to be added to baked goods as a functional ingredient.
