Growth behavior and resource potential evaluation of gas hydrate in core fractures in Qilian Mountain permafrost area, Qinghai-Tibet Plateau

The Qilian Mountain permafrost area located in the northern of Qinghai-Tibet Plateau is a favorable place for natural gas hydrate formation and enrichment,due to its well-developed fractures and abundant gas sources.Understanding the formation and distribution of multi-component gas hydrates in fractures is crucial in accurately evaluating the hydrate reservoir resources in this area.The hydrate formation experiments were carried out using the core samples drilled from hydrate-bearing sediments in Qilian Mountain permafrost area and the multi-component gas with similar composition to natural gas hydrates in Qilian Mountain permafrost area.The formation and distribution characteristics of multi-component gas hydrates in core samples were observed in situ by X-ray Computed Tomography(X-CT)under high pressure and low temperature conditions.Results show that hydrates are mainly formed and distributed in the fractures with good connectivity.The ratios of volume of hydrates formed in fractures to the volume of fractures are about 96.8%and 60.67%in two different core samples.This indicates that the fracture surface may act as a favorable reaction site for hydrate formation in core samples.Based on the field geological data and the experimental results,it is preliminarily estimated that the inventory of methane stored in the fractured gas hydrate in Qilian Mountain permafrost area is about 8.67×1013 m3,with a resource abundance of 8.67×108 m3/km2.This study demonstrates the great resource potential of fractured gas hydrate and also provides a new way to further understand the prospect of natural gas hydrate and other oil and gas resources in Qilian Mountain permafrost area.

Growth behaviors and emission properties of Co-deposited MAPbI_(3) ultrathin films on MoS_(2)

Hybrid organic–inorganic perovskite thin films have attracted much attention in optoelectronic and information fields because of their intriguing properties. Due to quantum confinement effects, ultrathin films in nm scale usually show special properties. Here, we report on the growth of methylammonium lead iodide(MAPbI_(3)) ultrathin films via co-deposition of PbI_2 and CH_3NH_3I(MAI) on chemical-vapor-deposition-grown monolayer MoS_(2) as well as the corresponding photoluminescence(PL) properties at different growing stages. Atomic force microscopy and scanning electron microscopy measurements reveal the MoS_(2) tuned growth of MAPbI_(3) in a Stranski–Krastanov mode. PL and Kelvin probe force microscopy results confirm that MAPbI_(3) /MoS_(2) heterostructures have a type-Ⅱ energy level alignment at the interface. Temperaturedependent PL measurements on layered MAPbI_(3) (at the initial stage) and on MAPbI_(3) crystals in averaged size of 500 nm(at the later stage) show rather different temperature dependence as well as the phase transitions from tetragonal to orthorhombic at 120 and 150 K, respectively. Our findings are useful in fabricating MAPbI_(3) /transition-metal dichalcogenide based innovative devices for wider optoelectronic applications.

Crack growth behavior of SRR99 single crystal superalloy under thermal fatigue

The thermal fatigue behavior of a single crystal superalloy SRR99 was investigated. Specimens with V-type notch were tested at the peak temperatures of 900, 1000, and 1100℃. The crack growth curves as a function of the number of cycles were plotted. With the increase of peak temperature, the crack initiation life was shortened dramatically. Through optical microscopy （OM） and scanning electron microscopy （SEM） observation, it was found that multiple small cracks nucleated at the notch tip region but only one or two of them continued to develop in the following thermal cycles. The primary cracks generally propagated along a preferential direction. Microstructure changes after thermal fatigue were also discussed on the basis of SEM observation.

Effect of Deposition Time on Microstructures and Growth Behavior of ZrC Coatings Prepared by Low Pressure Chemical Vapor Deposition with the Br2-Zr-C3H6-H2-Ar System

ZrC coatings were deposited on graphite substrates by low pressure chemical vapor deposition（LPCVD） with the Br2-Zr-C3H6-H2-Ar system. The effects of deposition time on the microstructures and growth behavior of ZrC coatings were investigated. ZrC coating grew in an island-layer mode. The formation of coating was dominated by the nucleation of ZrC in the initial 20 minutes, and the rapid nucleation generated a fine-grained structure of ZrC coating. When the deposition time was over 30 min, the growth of coating was dominated by that of crystals, giving a column-arranged structure. Energy dispersive X-ray spectroscopy showed that the molar ratio of carbon to zirconium was near 1：1 in ZrC coating, and X-ray photoelectron spectroscopy showed that ZrC was the main phase in coatings, accompanied by about 2.5mol% ZrO2 minor phase.

Thin-film growth behavior of non-planar vanadium oxide phthalocyanine

The thin film properties of organic semiconductors are very important to the device performance.Herein,non-planar vanadyl phthalocyanine(VOPc)thin films grown on rigid substrates of indium tin oxide,silicon dioxide,and flexible substrate of kapton by organic molecular beam deposition under vacuum conditions are systematically studied via atomic force microscopy and x-ray diffraction.The results clearly reveal that the morphology and grain size are strongly dependent on the substrate temperature during the process of film deposition.Meanwhile,the VOPc films with the structure of phase I or phase II can be modulated via in situ annealing and post-annealing temperature.Furthermore,the crystalline structure and molecular orientation of vapor-deposited VOPc can be controlled using molecular template layer 3,4,9,10-perylenetetracarboxylic dianhydride(PTCDA),the VOPc film of which exhibits the phase I structure.The deep understanding of growth mechanism of non-planar VOPc film provides valuable information for controlling structure-property relationship and accelerates the application in electronic and optoelectronic devices.

Anisotropic monolayer of ReX_(2)on Au foils for exploring abnormal growth behavior and electronic properties

As an emerging class of semiconducting transition metal dichalcogenides(TMDCs),two-dimensional(2D)rhenium dichalcogenides(ReX_(2),X=S or Se)have recently aroused great research interest due to their unique anisotropic structure(1T′phase),and the related novel properties and applications.Recently,many efforts have been devoted to the controllable syntheses of high-quality monolayer or few-layer ReX_(2)flakes/films by chemical vapor deposition(CVD),wherein the metallic Au foil is found to be a unique substrate,due to the relatively strong interfacial coupling between monolayer ReX_(2)and Au.And the conductive nature of Au enables in situ characterizations of the as-grown ReX_(2)samples,which is essential for exploring the fundamental properties and internal growth mechanisms.Hereby,this review focuses on the recent progresses on the CVD syntheses and in situ characterizations of high-quality monolayer ReX_(2)flakes/films and their heterostructures with graphene on Au foils.The effects of Au foils on improving the crystal quality and inducing the growth of monolayer ReX_(2)single crystals are intensively addressed.The crystallinity,domain morphology,atomic and electronic structures,as well as the growth behaviors of monolayer ReX_(2)flakes/films and graphene/ReX_(2)heterostructures on Au revealed by in situ characterization techniques are also highlighted.As contrasts,the growth behaviors of monolayer or few-layer ReX_(2)on insulating substrates are also discussed.Besides,the potential applications of 2D ReX_(2)in new-generation electronic,optoelectronic devices,and energy-related fields are also introduced.Finally,future research directions are also prospected for propelling the practical applications of 2D ReX_(2)materials in more versatile fields.

Bainite Growth Behavior at Early Stage of Transformation in a High Carbon Silicon-Containing Steel

The growth behavior at the early stage of bainitic transformation was investigated using optical microscopy,X-ray diffraction analysis and transmission electronic microscopy.The bainite was obtained by isothermal transformation at 200 ℃ only for a short time in a high carbon silicon-containing steel after austenitization at 200 ℃ only for 20 min.Transmission electronic microscopy shows that the bainite appears in the form of plates with a width of about 30 nm,and that the interface of the bainite leading tip is wedge shaped.X-ray diffraction analysis reveals that the bainite plates consist of single ferrite phase,with absence of carbides.The results confirm the occurrence of the moiré which suggests the existence of austenite grain boundaries at the bainite leading tip.Both the lateral growth and longitudinal growth of bainite have weak ability to traverse the lattice-distortion strain fields and austenite grain boundary.The austenite grain boundary impedes the longitudinal growth of the bainite plate,i.e.,the growth of bainite plate stops at the austenite grain boundary.The longitudinal growth of bainite associated with the features of shear mechanism can not completely be in accordance with that of martensitic transformation.

Insight into the growth behaviors of MoS_(2)nanograins influenced by step edges and atomic structure of the substrate

The step edges and intrinsic atomic structure of single-crystal substrate play a critical role in determining the growth pathways of transition metal dichalcogenide(TMD)grains,particularly whether the TMDs will grow into wafer-scale single-crystal or anisotropic nanoribbons.Hereby,we investigate the growth behaviours of the MoS_(2)nanograins on(0001)and()sapphire substrates.On one hand,the step edges formed on the(0001)surface after thermal treatment are found to promote the macroscopic aggregation of MoS_(2)nanograins and to form unidirectional large triangular islands along with the<>steps in the annealing process,while on the pristine(0001)surface,the MoS_(2)nanograins grow into a random network-like pattern.Moreover,oxygen treatment on the substrate can further enhance the growth of MoS_(2)nanograins.Transmission electron microscopy and fast Fourier transform patterns reveal that the substrate could modulate the orientation of MoS_(2)nanograins during their growing process.On the other hand,the MoS_(2)nanograins on the surface could self-assemble into one-dimensional nanoribbons due to the strong structural anisotropy of the substrate.In addition,the ratio of Raman intensities for peaks that correspond to the and A1g phonon modes shows a linear relationship with the grain size due to the change of the“phonon confinement”.Moreover,new peaks located at 226 and 280 cm−1 can be observed in the off-resonant and resonant Raman spectra for the MoS_(2)nanograin samples,respectively,which can be attributed to the scatterings from the edges of as-fabricated MoS_(2)nanostructures.

Stk2,a Mitogen-Activated Protein Kinase from Setosphaeria turcica,Specifically Complements the Functions of the Fus3 and Kss1 of Saccharomyces cerevisiae in Filamentation,Invasive Growth,and Mating Behavior

Setosphaeria turcica,an essential phytopathogenic fungus,is the primary cause of serious yield losses in corn; however,its pathogenic mechanism is poorly understood.We cloned STK2,a newly discovered mitogen-activated protein kinase gene with a deduced amino acid sequence that is 96% identical to MAK2 from Phaeosphaeria nodorum,56% identical to KSS1 and 57% identical to FUS3 from Saccharomyces cerevisiae.To deduce Stk2 function in S.turcica and to identify the genetic relationship between STK2 and KSS1/FUS3 from S.cerevisiae,a restructured vector containing the open reading frame of STK2 was transformed into a fus3/kss1 double deletion mutant of S.cerevisiae.The results show that the STK2 complementary strain clearly formed pseudohyphae and ascospores,and the strain grew on the surface of the medium after rinsing with sterile water and the characteristics of the complementary strain was the same as the wild-type strain.Moreover,STK2 complemented the function of KSS1 in filamentation and invasive growth,as well as the mating behavior of FUS3 in S.cerevisiae,however,its exact functions in S.turcica will be studied in the future research.

Effects of salinity on survival,feeding behavior and growth of the juvenile swimming crab,Portunus trituberculatus(Miers,1876)

Effect of salinity on survival,feeding behavior and growth of juvenile swimming crab P ortunus trituberculatus was investigated under 5 salinity levels of 5,10,20,30 and 40. The results show that the crab juveniles fed 2 or 3 times at the salinity 20 and 30,each lasted for about 25 minutes,for a total feeding time of 73.2±22.65 minutes per day. At these salinities,there were significantly higher in the frequency of feeding and in total feeding time than those at lower salinities of 5 and 10. All crab juveniles moulted when reared at a salinity of 20 during the 5 days duration of the experiment,which is significantly higher than those at other salinities. All juveniles survived at salinity 20,and the survivorship was not significantly different from that at 30,but was signif icantly higher than those at other salinities. The crab juveniles reared at a salinity of 20 had the highest value of food ration of 0.190 8±0.011 3 g/g BW,average body weight gain of 0.796±0.128 g,gain rate of 87%–96%,and food conversion ratio of 1.20±0.09. There was no significant difference in the values found between 20 and 30 but these values were significantly lower than that at the other salinities( P> 0.05). Highest activities of digestive enzymes(Amylase,Protease,Lipase) and lowest activities of protective enzymes(SOD,PO,CAT) were also obtained on crab juveniles reared at salinity of 20.

Effects of different feeding methods and space allowance on the growth performance, individual and social behaviors of Holstein calves

The importance of nutrient provisions and weaning methods for calves has been well established over the past few years,while as increasing interest has focused on contribution of animal behavior and their overall performance in production regimes.The present study investigated the effects of feeding methods and space allowance on growth performance,individual and social behaviors in Holstein calves.Twenty-four Chinese Holstein male and female calves were allocated to either an individual or group of 6 and fed either with a bucket or a teat.Milk replacer,calf starter,and Chinese wildrye were offered during the experiment.A fecal index used in the present study was defined as the total fecal scores/total number of calves in each treatment.The results showed that there was no significant difference among the 4 treatments in terms of feed intake,body weight,average daily gain,and fecal index.For the feeding behaviors,the ingesting milk time and ingesting milk rate were significantly affected by space allowance,while the feeding methods showed a significant influence on the bunting behavior of the calves.There was no significant difference among the 4 treatments in terms of licking fixtures,self-grooming,and lying down behaviors,irrespective of the feeding method or space allowance.However,sucking an empty bucket or the teat was significantly affected by the feeding method.Several selected group behaviors were examined in the present study,and similar values for sniffing the other calves,social grooming,and cross-sucking behaviors were observed.Overall,the present study demonstrated that different feeding methods and space allowances had a significant effect on the feeding behavior of calves,while the feed intake,growth performance,health condition,individual and group social behaviors were not significantly influenced.Furthermore,under intensified production systems,Holstein calves raised in a group may obtain a similar production performance,thus reducing management input and profitability compared with those kept individually.However,there may be competition during the feeding period.

A Review of Feeding Behavior, Growth, Reproduction and Aquaculture Site Selection for Green-Lipped Mussel, <i>Perna viridis</i>

Green-lipped mussel, Perna viridis is a warm water mussel species that is distributed widely in the Indo-Pacific regions. It is a commercially important species and has demonstrated a great culture potential in tropical countries. The feeding behavior of P. viridis is influenced by both seston concentration and its nutritional values. It is shown the mussels exhibit higher ingestion rate when the organic content of the seston is higher. Interestingly, several studies have reported that P. viridis can demonstrate selective feeding behavior towards phytoplankton. Short term studies have shown that the P. viridis exhibits preferentially ingestion of dinoflagellates, while long term studies show that the P. viridis has a higher growth rate during diatom blooms. Nevertheless, spawning of P. viridis is induced by high primary productivity at relatively high sea water temperature. In the temperate countries, spawning is seasonal but normally occurs in summer. In the tropical countries, however, the P. viridis has been shown to spawn all year-round with two peaks which coincide with monsoon seasons. The site selection is critically important when considering the green mussel culture. Feasibility study for P. viridis farming is normally carried out first in order to evaluate the environmental conditions of the site. This paper attempts to review the current knowledge of biology, selective feeding behaviour, growth, reproductive and the aquaculture site selection methods for green-lipped mussel.

Kinetic Behaviors of a Competitive Population and Fitness System in Exchange-Driven Growth

We proposed an aggregation model of two species aggregates of fitness and population to study the inter-action between the two species in their exchange-driven processes of the same species by introducing the monomer birthof fitness catalyzed by the population,where the fitness aggregates perform self-death process and the population aggre-gates perform self-birth process.The kinetic behaviors of the aggregate size distributions of the fitness and populationwere analyzed by the rate equation approach with their exchange rate kernel K_1(k,j) = K_1kj and K_2(k,j) = K_2kj,the fitness aggregate's self-death rate kernel J_1(k) = J_1k,population aggregate's self-birth rate kernel J_2(k) =J_2k andpopulation-catalyzed fitness birth rate kernel I(k,j) = Ikj^v.The kinetic behavior of the fitness was found dependingcrucially on the parameter v,which reflects the dependence of the population-catalyzed fitness birth rate on the size ofthe catalyst (population) aggregate.(i) In the v≤0 case,the effect of catalyzed-birth of fitness is rather weak and theexchange-driven aggregation and self-death of the fitness dominate the process,and the fitness aggregate size distributionα_k(t) does not have scale form.(ii) When v>0,the effect of the population-catalyzed birth of fitness gets strong enough,and the catalyzed-birth and self-death of the fitness aggregates,together with the self-birth of the population aggregatesdominate the evolution process of the fitness aggregates.The aggregate size distribution α_k (t) approaches a generalizedscaling form.

Effect of behavior training on learning and memory of young rats with fetal growth restriction

Objective: To investigate the effect of behavior training on the learning and memory of young rats with fetal growth restriction (FGR). Methods: The model of FGR was established by passive smoking method to pregnant rats. The new-born rats were divided into FGR group and normal group, and then randomly subdivided into trained and untrained group respectively. Morris water maze behavior training was performed on postnatal months 2 and 4, then learning and memory abilities of young rats were measured by dark-avoidance testing and step-down testing. Results: In the dark-avoidance and step-down testing, the young rats’ performance of FGR group was worse than that of control group, and the trained group was better than the untrained group significantly. Conclusion: FGR young rats have descended learning and memory abilities. Behavior training could improve the young rats’ learning and memory abilities, especially for the FGR young rats.

Kinetic Behaviors of Catalysis-Driven Growth of Three-Species Aggregates on Base of Exchange-Driven Aggregations

我们建议一个可解决的聚集模型在一个社会模仿人口 A，财产 B，和可以计量的资源 C 的进化。在这个系统，人口和财产总数自己与率内核 K 1(k, j 通过自我交换成长)= K 1 kj 和 K 2(k, j )= K 2 kj 分别地。资源总数的聚集进化上的人口和财产聚集的行动被资源总数的催化人口的单体死亡和资源总数的催化财产的单体出生与率核 J 1(k, j 描述)= J 1 k 和 J 2(k, j )= J 2 k ，分别地。同时，财产和资源总数接合用率核催化人口总数的单体出生我1(k, i ， j )=我 1 ki μ j η,和人口和资源总数接合用率核催化财产总数的单体出生我2(k, i ， j )=我 2 ki v j η。种类 A， B，和 C 的运动行为借助于吝啬地的率方程途径被调查。资源总数的进化上的催化人口的死亡和催化财产的出生的效果基于人口和财产的自我交换出现在有效形式。有效催化人口的死亡和催化财产的出生的系数分别地被表示为 J 1e= J 1/K1 和 J 2e= J 2/K2, 。C 种类的总数尺寸分发被发现被在有效死亡和有效出生之间的比赛关键地统治。它在 J 1e【 J 2e, J 1e= J 2e, 和 J 1e 的情况中满足常规可伸缩形式，概括可伸缩的形式，和修改可伸缩的形式 】 J 2e, 分别地。同时，我们也发现总数人口的尺寸分布，财产两个都为不同参数 μ ， ν ，和 η 掉进二个不同范畴：(i) 什么时候 μ =ν =η = 0 并且 μ =ν = 0， η = 1，人口和财产总数服从概括可伸缩形式；并且(i i ) 什么时候 μ =ν = 1， η = 0，并且 μ =ν =η = 1，人口和财产总数经历在有限时间的转变和可伸缩的形式毁坏的冻结。

面向数字社会的学生社群互动行为分析

命运与共是当今世界的显著标志,人际交往对于社会生产与发展具有重要现实意义。信息技术的发展扩大了学生的成长空间,数字交往成为当代学生主要的人际互动形式,网络社群则成为学生成长的主要空间。然而,这也导致学生直面数字社交带来的交往异化和主体性丢失问题。因此,研究从交往理性的视角构建了数字社会CSS架构,涵盖数字文化(Digital Culture)、主体空间(Individual Space)和社会秩序(Social Order)三个层面,该架构为数字社会成员在新时代的生存发展和社会交往提供了可信机理。基于此架构详细分析了个体面向数字社会所应具备的胜任能力,具体包含数字文化中的工具意识、数字素养和主体效能;主体空间中的自我意识、身份认同和行为约束以及社会秩序中的群体意识、情绪驾驭和社会参与。

基于FP-growth算法的多尺度用电异常行为检测方法

异常用电行为检测直接关系到电力公司的利益。针对上述问题,提出一种基于FP-growth算法的多尺度用电异常行为检测方法。通过采集器远程获取用电数据,并对缺失数据填补和数据进行标准化处理。通过计算特征的重要性指数和贡献率选取多尺度用电行为特征。利用FP-growth算法建立特征与用电行为之间的关联规则,根据支持度和置信度判断是否存在异常,实现用电异常行为检测。实验结果表明,所研究方法的F1值始终高于0.8,说明该方法的检测更为准确。

Very High Cycle Fatigue Behaviors and Surface Crack Growth Mechanism of Hydrogen-Embrittled AISI 304 Stainless Steels

The influence of hydrogen embrittlement on the fatigue behaviors of AISI 304 stainless steel is investigated. The fatigue endurance limits of the untreated and hydrogen-embrittled materials were almost the same at 400 MPa, and hydrogen embrittlement had little influence even though the sample contained about 8.1 times more hydrogen. Thus, the sensitivity of hydrogen gas in this material is very low. A surface crack initiation, growth, coalescence, and micro ridge model is proposed in this study. Slip line formation?&rArr;microcrack formation?&rArr;increases in the crack width, and blunting of the crack tip as it grows?&rArr;formation of many slip lines because of deformation in the shear direction?&rArr;growth of the crack in the shear direction, forming micro ridges, coalescence with adjacent cracks &rArr;?continuous initiation, growth, coalescence, and ridge formation of surface cracks and specimen breakage.

投喂频率对红鳍东方鲀生长和行为的影响

以红鳍东方鲀(Takifugu rubripes)幼鱼为实验对象,研究在日投喂量相同的条件下,不同投喂频率[3次/d(F3)、4次/d(F4)和5次/d(F5)]对幼鱼生长和行为的影响。结果表明:(1)F4组幼鱼的生长性能显著高于F3和F5组(P<0.05);(2)在实验结束时,不同处理组幼鱼的游泳速度差异显著,从大到小依次为F4>F3>F5(P<0.05),F4组幼鱼的角速度显著高于F3和F5组(P<0.05),F4组幼鱼的加速度和活跃度显著低于F3和F5组(P<0.05),F3组幼鱼的对象间距离显著高于F4和F5组(P<0.05);(3)GLMMs的结果表明,F4组幼鱼的游速受到实验时间与投喂频率交互效应的影响显著(P<0.05),各处理组之间的比较结果显示,实验时间和投喂频率的交互效应对F5组幼鱼的加速度有正向效果,但其显著降低了F5组幼鱼的对象间距离。综上所述,不同投喂频率对幼鱼的生长性能和行为表现具有显著影响。实验推测4次/d的投喂频率可能改变了幼鱼的能量分配,更多的能量被用于生长和游泳,使得幼鱼的生长性能有所提高,并且增强了鱼群的整体凝聚力和稳定性。因此,建议红鳍东方鲀幼鱼的投喂频率为4次/d,并且可以将游速和对象间距等指标作为监测红鳍东方鲀摄食行为的主要参数。