Effect of microwave pre-treatment on physical quality,bioactive compounds,safety risk factor,and storage stability of peanut butter

Microwave,as a new heat treatment technology,has the characteristics of uniform and fast heating speed.It is an energy-saving technology known for improving oilseed product quality.Its efficiency mainly depends on the roasting power and time.However,the production of high-quality peanut butter using short-time roasting con-ditions are limited.Herein,we determined an appropriate microwave roasting power and time for peanuts and evaluated its impacts on the quality of peanut butter.Different roasting powers(400 W,800 W and 1200 W)and times(4,4.5,5,and 5.5 min)were preliminarily tested.Among them,800 W at 5 min was the most suitable.The roasting efficiency was further evaluated using color,sensory,bioactive compounds,storage stability,and safety risk factors of peanut butter produced from four peanut cultivars(Silihong,Baisha-1016,Yuanza-9102,and Yuhua-9414).The pre-treated butter obtained from three cultivars(Silihong,Yuanza-9102,and Yuhua-9414)with moisture content between 5%and 7.2%had a similar sensory score(6-7)as the commercial on a 9-point hedonic scale compare to the other.The color of the pre-treated peanut butter varies statistically with the commercial but remained in the recommended range of Hunter L*values of 51-52,respectively,for high initial moisture peanut cultivars.The total polyphenol(35.20-31.59±0.59μmol GAE/g)and tocopherol(19.05±0.35 mg/100 g)content in the butter obtained from three cultivars(Yuahua-9102,Yuhua,and Baisha-1016)and Silihong respectively,were significantly(P<0.05)higher than those in the commercial butter.The induction times of all pre-treated butter(19.80±0.99-7.84±0.07 h)were significantly(P<0.05)longer during storage at accelerated temperature than commercial samples.In addition,no benzo[a]pyrene was found in the pre-treated samples.Collectively,the microwave pretreated peanut butter was superior to the commercial one.These findings provided data support and a reference basis to promote microwave use for peanut butter production.

Investigation of spherical and concentric mechanism of compound droplets

Polymer shells with high sphericity and uniform wall thickness are always needed in the inertial confined fusion(ICF)experiments.Driven by the need to control the shape of water-in-oil(W1/O)compound droplets,the effects of the density matching level,the interfacial tension and the rotation speed of the continuing fluid field on the sphericity and wall thickness uniformity of the resulting polymer shells were investigated and the spherical and concentric mechanisms were also discussed.The centering of W1/O compound droplets,the location and movement of W1/O compound droplets in the external phase(W2)were significantly affected by the density matching level of the key stage and the rotation speed of the continuing fluid field.Therefore,by optimizing the density matching level and rotation speed,the batch yield of polystyrene(PS)shells with high sphericity and uniform wall thickness increased.Moreover,the sphericity also increased by raising the oil/water(O/W2)interfacial tension,which drove a droplet to be spherical.The experimental results show that the spherical driving force is from the interfacial tension affected by the two relative phases,while the concentric driving force,as a resultant force,is not only affected by the three phases,but also by the continuing fluid field.The understanding of spherical and concentric mechanism can provide some guidance for preparing polymer shells with high sphericity and uniform wall thickness.

DETERMINATION OF STABILITY CONSTANTS OF THE COORDINATION COMPOUNDS OF Au(Ⅲ)-2-MERCAPTOPYRIDINE-1-OXIDE AND METHYL DERIVATIVES——METHOD OF DUAL-WAVELENGTH CORRESPONDING SOLUTIONS

In this paper,we report the deductive formula used for the method of dual-wavelength corresponding solutions under condition of having ligand interference and the stability constants of three new coordination compounds [AuL_2]^+determined with this method.The stability of the three compounds,the necessity of controlling pH in experimental systems and the advantage of this method are discussed in detail.

ANALYSIS OF ROLL SYSTEM STABILITY ABOUT ALUMINUM FOIL MILLS

To improve roll system stability of aluminum foil mills, roll system stability of 2200 highspeed aluminum foil mill is analyzed with energy stable method. Two different restrictive conditions which gaps between chock of work roll and window of stand whether exist or not, are studied respectively. A new concept of roll system with open /closed compound pair conies up with as well for re-newably synthesizing restrictive mechanism of aluminum foil mills' chock. Through these studies, the conflict, whether reserving the gap for the roller replacement or eliminating the gap for roller's normal work, is successfully settled. This concept and analyzed result give the actual mechanism with open/closed compound restriction and the method of realizing high-speed rolling and prolonging longevity of end thrust bearing on work roll. It has important theoretical meaning and engineering value for modern technical reform of aluminum foil mills and plate strip mills.

Structure, magnetic properties, and thermal stability of Sm(1-x)Tm_xCo_5compounds

Structure, magnetic properties, and thermal stability of ternary Sm1-xTmxCo5 compounds were studied via X-ray diffraction（XRD）, thermal magnetic analysis（TMA）, and magnetic measurements. XRD results show that all the compounds have a main phase of hexagonal CaCu5-type crystal structure with small amount of impurity phases; increasing Tm content is associated with contraction of the hexagonal unit cell in the direction of the c axis and expansion of the a and b parameters. TMA results indicate that the Curie temperature（TC） of Sm1-xTmxCo5 compounds gets higher with the increase in Tm content.Magnetic measurements show that both the magnetic anisotropy field（HA） and the magnetization at an applied field of 7 T（M7 T） decrease with the increase of Tm content. However, the thermal stability of both the HAand M7 Tof all the Tm doped compounds is remarkably improved compared with that of the pure SmCo5 compound, leading to the result that both the M7 Tand HAof Sm0.8Tm0.2Co5 .2are higher than those of SmCo5 compound at 473 K, which indicates the good potential of Tm doped compound in the practical applications at elevated temperature.