Modifications in aroma characteristics of'Merlot'dry red wines aged in American,French and Slovakian oak barrels with different toasting degrees

Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to wines.In the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermented in two types of fermenters(stainless steel tank and rotated oak barrel)and aged in six types of oak barrels(three geographic origins×two toasting degrees)for different time(0,3,6 and 9 months,respectively).Results showed that 30 volatiles were associated with barrels and increased during oak aging.The fermenters could influence the intensities of the toast,leathery,smoky,fruity,floral and caramel aromas.The concentration of whisky lactone,eugenol,cis-isoeugenol,and the intensities of the toast and spicy aromas were highest in the wines aged in American oak and were lowest in the wines aged in French oak barrels.The concentrations of guaiacol,syringol,trans-isoeugenol,furfural alcohol,vanilla,cis-whisky lactone enabled the medium toasting barrels to be distinguished from the light toasting ones.The compounds originating from the barrels could be used to distinguish the types of different barrels,but the other general grape-derived and fermentation-derived volatiles could not.The fermenters,oak species and toasting degrees of the barrels all had significant effects on the aroma profiles of the aged‘Merlot’dry red wines,but the influence of the geographic origin was not obvious.

基于BLI技术的BamAβ-barrel结合化合物检测方法的建立

目的以革兰阴性菌外膜蛋白折叠辅助因子关键蛋白BamA为靶蛋白,基于生物膜干涉(Biolayer interferometry,BLI)技术建立化合物与BamA蛋白β折叠结构域(BamA_(β-barrel))结合活性的评价方法,为建立靶向BamA蛋白的抗革兰阴性菌先导物奠定基础。方法应用BLI方法检测BamA_(β-barrel)与已知的阳性化合物darobactin的结合活性。原核表达并纯化带有His标签的大肠埃希菌BamA_(β-barrel)蛋白,使用表面活性剂LDAO对其进行复性和折叠;使用生物素标记折叠和未折叠蛋白,并结合到超级链霉亲和素(super streptavidin,SSA)生物传感器,然后检测蛋白与不同浓度的darobactin结合信号的变化,同时做无蛋白或darobactin稀释液对照;空白对照采用未结合生物素化的BamA_(β-barrel)蛋白的传感器,检测上述系列稀释样品。相应信号采用Steady state analysis方式拟合分析,计算平衡常数(KD)值。结果成功获得高纯度的折叠状态BamA_(β-barrel)蛋白,通过BLI技术检测到折叠状态的BamA_(β-barrel)与阳性化合物darobactin具有良好结合活性且呈现浓度依赖性,R^(2)为0.9998,KD值为(2.2E-06±8.0E-08)M。结论基于BLI技术成功建立了折叠状态的BamA_(β-barrel)-化合物结合活性的评价方法,为后续BamA蛋白靶向性抗革兰阴性菌抗生素的发现建立基础。

Symbols in The Magic Barrel

The article takes the famous modern American Jewish writer Bernard Malamud’s novel The Magic Barrel as the object of study,and uses symbolism to interpret it,analyzing it one by one in terms of the magic barrel,the colors,the seasons and the windows,respectively,so as to reveal the process of getting rid of the childishness within the novel’s male protagonist,Leo Finkel,who is maturing,as well as the novel’s Jewish theme of searching for the soul of the self.

幼年及成年SD大鼠Barrel脑区的变化

目的研究幼年和成年SD大鼠Barrel脑区的发育及变化。方法应用细胞色素氧化酶组织化学法研究成年SD鼠Barrel脑区的精确定位,及不同年龄段SD大鼠(出生后20d及3月龄成年SD大鼠)Barrel脑区的发育情况。结果成年SD大鼠的Barrel脑区面积明显小于年轻鼠(P<0.01);发育过程中,Barrel脑区各列之间的间距缩小,尤其是D和E列之间的间距;应用Nissl复染后发现,分隔各个Barrel桶之间的间距缩小,且神经元数目减少;成年SD大鼠的Barrel桶中高活性细胞色素氧化酶细胞比例明显高于年轻鼠(P<0.01)。结论啮齿类动物躯体感觉皮层Barrel脑区神经网络的排布精细,其构筑在发育过程中存在着微妙的变化。

SD大鼠Barrel脑区氧化酶活性区域及其特殊细胞构筑研究

【目的】确定控制大鼠胡须感觉的大脑皮质Barrel脑区的氧化酶活性区和该区的细胞构筑，为研究大脑皮质功能奠定基础。【方法】用多聚甲醛固定后的SD鼠脑组织修块、切片，应用氧化酶酶组织化学法及尼氏染色和尼氏复染等方法定位了SD鼠Barrel脑区，并观察了其脑区特殊的细胞构筑。【结果】SD鼠Barrel脑区定位结果表明，控制SD鼠胡须感觉的Barrel脑区高氧化酶活性区域位于皮层下约405～720μm；脑区的神经细胞成特殊的环状分布，通常在控制1根胡须的Barrel桶内同时包括数目不等的亚结构，亦成类似的环状排列，在这些小圆环状亚结构中包含有排布规则的高活性氧化酶细胞。【结论】Barrel脑区的精细排布及其内部存在的圆环状细胞亚结构，提示这些结构在感觉皮层神经网络运作中发挥着重要作用。

Modeling and simulation of bullet-barrel interaction process for the damaged gun barrel

In this paper,the influences of bore damage on the bullet-barrel interaction process and the mechanism of how bore damage results in the end of a machine gun barrel’s service life were studied,which had seldom been paid attention to in the past several decades.A novel finite element mesh generation method for the damaged barrel and a new transient coupled thermo-mechanical finite element(FE)model,which were based on the damage data obtained through barrel life tests,were developed to simulate the interior ballistics process of a coupled bullet-barrel system.Additionally,user subroutine VUAMP was developed in the FE model in order to take the bullet base pressure brought by propellant gas into account.Good consistency between the simulation results and the experimental results verified the preciseness of the proposed mesh generation method and the FE model.The simulation results show that the increase of bullet’s initial disturbance at the muzzle and the variation of its surface morphology caused by bore damage are primarily responsible for the life end of this 12.7 mm machine gun barrel.

GABAergic神经元在BARREL和VPM区组织结构及形态特点的研究（英文）

啮齿类以胡须为感觉器官，通过其摆动获取物体质地和空间位置信息。在老鼠的每一侧嘴部，有5列水平排布的机械感受器，位于胡须下面的囊泡中。胡须摆动可打开机械型离子通道，产生动作电位，经传出纤维传入位于脑干的三叉神经节中，从而使三叉核团的谷氨酸型突触产生兴奋。三叉丘脑核团在三叉核团处形成躯体代表区，称为“barrelettes”。接着脑干中的这些神经元又将信息传入丘脑的Ventral poslerior medial（VPM）核团，

The law of barrel wear and its application

A power function relation between number of rounds and barrel wear amount is created based on the test data from firing of large-caliber barrels. The function is optimized to fully fit the test data. A new concept of diameter change rate of bore is proposed and the law of barrel wear is put forward by means of comparing the diameter change rates for large-caliber barrels with different calibers. It is shown that the law of barrel wear is successful in barrel life prediction.

GABAergic神经元在BARREL和VPM区组织结构及形态特点的免疫组织化学研究

[目的]研究GABAergic神经元在VPM和"barrel"区的组织结构及形态特点;[方法]通过免疫组织化学的方法和激光共聚焦电子显微镜研究GABAergic神经元在VPM和"barrel"区分布状态;[结果]GABAergic神经元在VPM和"barrel"区分布状态不同,信息传递这2个区域编码程度也不一样;GABAergic在VPM区主要分布在列与列之间,且呈非对称分布,而GABAergic神经元的胞体、树突和轴突出现限定在"barrel"内,与周围"barrel"很少形成突触联系。[结论]提示VPM和"barrel"可能在信息传递及处理过程中具有不同的功能。

Study on performance degradation and failure analysis of machine gun barrel

An increase in the use of the gun barrel will cause wear of the inner wall,which reduces the muzzle velocity and the spin rate of the projectile.The off-bore flight attitude and trajectory of the projectile also change,affecting the shooting power and the accuracy.Exterior ballistic data of a high-speed spinning projectile are required to study the performance change.Therefore,based on the barrel’s accelerated life test,the whole process of projectile shooting is reproduced using numerical simulation technology,and key information on the ballistic performance change at each shooting stage are acquired.Studies have shown that in the later stages of barrel shooting,the accuracy of shooting has not decreased significantly.However,it is found that the angle of attack of the projectile increases as the wear of the barrel increases.The maximum angle of attack reaches 0.106 rad when the number of shots reaches 4300.Meanwhile,elliptical bullet hole has appeared on the target at this shooting stage.Through combining external ballistic theory with simulation results,the primary reason of this phenomenon is found to be a significant decrease in the muzzle spin rate of the projectile.At the end of the barrel life,the projectile muzzle spin rate is 57.5%lower than that of a barrel without wear.

Development of multi-physics numerical simulation model to investigate thermo-mechanical fatigue crack propagation in an autofrettaged gun barrel

In this research,a detailed multi-physics study has been carried out by numerically simulating a solid fractured gun barrel for 20 thermo-mechanical cycles.The numerical model is based on thermal effects,mechanical stress fields and fatigue crack mechanics.Elastic-plastic material data of modified AISI 4340 at temperatures ranging from 25 to 1200℃and at strain rates of 4,16,32 and 48 s^(-1) was acquired from high-temperature compression tests.This was used as material property data in the simulation model.The boundary conditions applied are kept similar to the working gun barrel during continuous firing.A methodology has been provided to define thermo-mechanically active surface-to-surface type interface between the crack faces for a better approximation of stresses at the crack tip.Comparison of results from non-autofrettaged and autofrettaged simulation models provide useful information about the evolution of strains and stresses in the barrel at different points under combined thermo-mechanical loading cycles in both cases.The effect of thermal fatigue under already induced compressive yield due to autofrettage and the progressive degradation of the accumulated stresses due to thermo-mechanical cyclic loads on the internal surface of the gun barrel(mimicking the continuous firing scenario)has been analyzed.Comparison between energy release rate at tips of varying crack lengths due to cyclic thermo-mechanical loading in the non-autofrettaged and autofrettaged gun has been carried out.

Barrel Shifter的三种实现方案

本文详细地研究了现代RISC微处理机的一个重要功能部件BS(Barrel-Shifter)的三种实现方案,并从VLSI实现的角度对三种方案进行了比较,根据比较结果,最后决定在我们自行设计的32位嵌入式定点RISC微处理机中将采用部分译码的方案。

Research on Effect of Adding Nanomaterial to Propellant on Gun Barrel

The barrel lifes of three small caliber rifles were tested by using the propellant with nanomaterial and the standard propellant respectively. The test results show that the service life increases observably due to adding nanomaterial to the propellant. Then, the influence of the nanomaterial on the tube was researched by splitting the two barrels tested and detecting their inner surfaces. It was found that the erosion of the barrel bore is reduced observably by using the propellant with nanomaterial. And it makes the volume and the size of the gun chamber change less. Therefore, the barrel life can be prolonged by adding the nanomaterial in the propellant.

The uncertainty propagation analysis of the projectile-barrel coupling problem

Based on the model which couples the projectile and gun barrel during an interior ballistic cycle,the uncertainty propagation analysis of the model is presented caused by the uncertainty of the input parameters.The Bootstrap method is employed to calculate the statistical moments(i.e.the mean,variance,skewness coefficient and kurtosis coefficient)of the parameters of the projectile.Meanwhile,the maximum entropy method is used to estimate the probability density function(PDF)and the cumulative density function(CDF),the interval of the parameters of the projectile are also given.Moreover,the results obtained are compared to the results calculated by Monte Carlo(MC)method to verify the effectiveness of the presented method.Finally,the rule and the uncertainty propagation model of the projectile-barrel coupling system are given with the variation of the uncertainties of the input parameters.

Experimental study of the mechanical property of barrel processed by cold radial forging

The cold radial forging process usually introduces some changes of the material, such as the increased strength, the decreased plasticity and the introduction of anisotropic mechanical prop- erty. To obtain the changes of mechanical property of barrel processed by cold radial forging, the tangential mechanical properties of the barrel blank and the forged barrel are measured with a de- signed test based on the plastic deformation analysis for a barrel and by applying internal pressure, and their axial mechanical properties are measured by the tensile test. The changes of mechanical property of barrel processed by cold radial forging are obtained by comparing the mechanical proper- ties of the barrel blank and the forged barrel. The tangential and axial flow stresses of the barrel blank and the forged barrel are also presented.

Mechanical assisted electroless barrel-plating Ni-P coatings on magnesium alloy

A mechanically assisted electroless barrel-plating Ni-P was carried out in a rolling drum containing Mg alloy specimens and ceramic balls, which was submerged in a bath containing electroless plating solution deposited by this novel technique have a It is demonstrated that the Ni-P coatings crystallized Ni-P solid solution structure, showing fine-grains, higher hardness, and higher corrosion resistance compared with the conventional electroless plated amorphous Ni-P coatings. After heat treatment at 400 ℃ for 1 h, the structure of such Ni-P coatings were transformed to a structure with Ni-Ni3P double phases, and cracks in these coatings could not be observed, whereas cracks appeared seriously in the conventional electroless plated Ni-P coating after same heat treatment. Therefore, both hardness and corrosion resistance of these Ni-P coatings can be improved further by heat treatment. All of these beneficial effects can be attributed to the role of mechanical attrition during the mechanically assisted electroless barrel-plating process.

The detrimental effect of autofrettage on externally cracked modern tank gun barrels

Overstraining gun tubes has a twofold advantage. First, it enables the increase of the Safe Maximum Pressure(SMP) in the tube, resulting in a higher muzzle velocity which extends the gun's range and its projectile kinetic energy. Second, it reduces the tube's susceptibility to internal cracking which prolongs its fatigue life. Unfortunately, autofrettage also bears an inherent detrimental effect as it considerably increases the tensile hoop stress at the outer portion of the barrel's wall, which enhances external cracking of the tube by increasing the prevailing Stress Intensity Factor(SIF). In order to quantify this disadvantageous effect, 3-D Mode I SIFs distributions along the front of a single external radial semielliptical crack initiating from the outer surface of an autofrettaged modern gun barrel, overstrained by either the Swage or the Hydraulic autofrettage processes, are evaluated. The analysis is performed by the finite element(FE) method, using singular elements along the crack front. Innovative residual stress fields(RSFs), incorporating the Bauschinger effect for both types of autofrettage are applied to the barrel.Hill's [1] RSF is also applied to the tube for comparison reasons. All three RSFs are incorporated in the FE analysis, using equivalent temperature fields, Values for K_(IA)-the SIF resulting from the tensile residual stresses induced by autofrettage are evaluated for: a typical barrel of radii ratio R_o/R_i = 2, crack depth to wall-thickness ratios(a/t = 0.005-0.1),crack ellipticities(a/c = 0.2-1.0),and five levels of Swage,Hydraulic and Hill's autofrettage(e = 40%,60%,70%,80%,and 100%). In total,375 different 3-D cases are analyzed. The analysis demonstrates undoubtedly the detrimental effect of all types of autofrettage in increasing the prevailing effective stress intensity factor of external cracks, resulting in crack initiation enhancement and crack growth rate acceleration which considerably shortens the total fatigue life of the barrel. Nonetheless, the detrimental effect is autofrettage-type dependent. Swage and Hydraulic autofrettage RSFs differ substantially from each other. The disadvantageous effect of Swage autofrettage is much greater than that resulting from Hydraulic autofrettage. The results also emphasize the significance of the Bauschinger effect and the importance of the 3-D analysis.

Amending Research on the Expression of the Contact Force of the Spindle Barrel Finishing Based on EDEM Simulation

The spindle barrel finishing is commonly used to improve the surface integrity of the important parts of the high-end equipment while it is difficult to provide enough test artifacts for the traditional trial and error experiment to obtain the desirable processing technology.The EDEM simulation of the spindle barrel finishing can provide effective help for the process design,however,the difference between the simulation and experiment is closely related to the selection of the contact model during simulation.In this paper,simulations and experiments are conducted based on the identical apparatus and conditions to facilitate the comparison and validation between each other.Based on the Hertz contact theory,the effect of the material properties of contact objects and the relative position of the workpiece on the contact force is qualified.The expression of the correlation coefficient of the contact model is deduced.Then the formula for calculating the contact force between the barrel finishing abrasive and the workpiece that includes influence coefficient of the material properties and the relative positions is established.Finally,the contact force calculation formula is verified by changing the rotating speed.The result shows that the material correction coefficient ranges from 1.41 to 2.38,which is inversely related to the equivalent modulus E.The position correction coefficient ranges from 2.0 to 2.3.The relative error value between the calculation result and the experimental test result is from 0.58%to 14.07%.This research lay a theoretical foundation for the correction theory of the core elements of the spindle barrel finishing process.

Research on Prediction Model for Erosion and Abrasion of Barrel Based on LSSVM

To predict the erosion and abrasion of high bore pressure tank gun barrel, the least square support vector machine (LSSVM) algorithm was used. Based on the gun firing test data, the prediction model for barrel's erosion and abrasion was established. It was adopted to predict the wear increment of gun barrel. The results show that the prediction values given by the model coincide with the measured data better, and the model can predict the barrel's wear accurately and rapidly.

Analysis for the residual prestress of composite barrel for railgun with tension winding

Based on the elastic theory of cylindrical shells and the theory of composite laminates,a prediction model for the residual prestress of the simplified round composite barrel for railgun is established.Only the fibre pretension is considered in this model.A three dimensional numerical simulation for the residual prestress in the railgun barrel is carried out,by combining the temperature differential method with the element birth and death technology.The results obtained by the two methods are compared.It reveals that the distribution trends of residual prestress are consistent.And the difference for residual prestress in the filament wound composite housing of barrel is relatively small.The same finite element method is used to analysis the residual prestress in the non-simplified composite barrels for railgun,which are under different control modes of winding tension.The results mean that the residual prestress in barrel will increase while the taper coefficient for winding is decreasing.Therefore,the sealing performance in bore is improved,but the strength of the filament wound composite housing drops.In addition,the axial and circumferential residual prestress in the filament wound composite housing with constant torque winding are close to the ones in iso-stress design for barrel.