Integrated Modelling of Microstructure Evolution and Mechanical Properties Prediction for Q&P Hot Stamping Process of Ultra‑High Strength Steel

High strength steel products with good ductility can be produced via Q&P hot stamping process,while the phase transformation of the process is more complicated than common hot stamping since two-step quenching and one-step carbon partitioning processes are involved.In this study,an integrated model of microstructure evolution relating to Q&P hot stamping was presented with a persuasively predicted results of mechanical properties.The transformation of diffusional phase and non-diffusional phase,including original austenite grain size individually,were considered,as well as the carbon partitioning process which affects the secondary martensite transformation temperature and the subsequent phase transformations.Afterwards,the mechanical properties including hardness,strength,and elongation were calculated through a series of theoretical and empirical models in accordance with phase contents.Especially,a modified elongation prediction model was generated ultimately with higher accuracy than the existed Mileiko’s model.In the end,the unified model was applied to simulate the Q&P hot stamping process of a U-cup part based on the finite element software LS-DYNA,where the calculated outputs were coincident with the measured consequences.

Physicochemical and Sensory Properties of japonica Rice Varied with Production Areas in China

Northeast of China and Jiangsu Province are major production areas of japonica rice in China.Rice from northeast of China is well-known for its good-eating and appearance quality,and that from Jiangsu Province is viewed as inferior.However,little is known concerning the difference in physicochemical and sensory properties of rice between the major two production areas.Analysis of 16 commercial rice samples showed marked differences in physicochemical properties,including chalky grain rate,contents of amylose and protein and pasting properties between the two main areas.Northeastern rice contained more shortchain amylopectin as compared with Jiangsu rice.However,Jiangsu rice is comparable to northeastern rice in terms of sensory quality including overall acceptability and textural properties of springiness,stickiness and hardness as evaluated by trained panel.Our results indicated the limitation of conventional index of physicochemical properties,and suggested the necessity of identification of new factors controlling rice sensory property.In addition,the taste analyzer from Japan demonstrates limitation in distinguishing the differences between northeastern and Jiangsu rice,and therefore needs localization to fit China.

Studies on the Absorption of NO_2 by Polyethylene Glycol and the Oxidizing Properties of the Resulting Absorbent Product

PEG (Polyethylene glycol average molecular weight 300) is used as absorbent of NO2. The absorption efficiency is found to reach up to 97%. The absorbing product, PEG NO2, can be used to cleave benzyl ethers mildly and selectively to benzaldehyde and corresponding fatty alcohols, showing that PEG is a valuable oxidizing agent of benzyl ethers. As a carrier of NO2.PEG can be recovered and utilized repeatedly after the oxidation.

Improvement of Concrete Properties and Reinforcing Steel Inhibition Using a Natural Product Admixture

The use of a natural white juice, taken from magrabe banana stem, as concrete admixture to improve mechanical and physicrvchemical properties of concrete has been studied. The compressive strength, bulk density the free lime liberated during hydration and the combined water content were determined. The results indicate that the admixture acts as a retarder in most cases and as accelerator in some ones. Also, the admixture effect on the corrosion resistance of the reinforcing steel against surrounding aggressive media has been investigated using galvanostatic polarization technique. The addition of 0.2% admixture leads to the more inhibition of the steel

Technology Development and Market Trends of Laundry Detergent Sheets

Laundry detergent sheets have appeared in Chinese market and developed rapidly in the past year. The technology development, product properties and development problems were discussed. Meanwhile, the properties and performances of the novel laundry detergent were studied, and the development trend of product was also forecasted.

Studies on the seed production properties of Hunong 5s/Teqing 2

From Nongken 58s/Laser 4 // Xiandang, aphotoperiod-sensitive genic male sterile indicarice line, Hunong 5s was developed, and au-thorized by Hubei Province in 1992, and by theCommittee of the State Science Foundation ofChina in 1993. Hunong 5s was crossed to a in-dica restorer line Teqing 2 to produce a two-line Fhybrid Hunong 5s/Teqing 2. Growth and blossom characteristics of thetwo parents and the seed production propertieswere studied in this experiment. The resultswere as follows: Hunong 5s and Teqing 2 wereboth medium-maturing rice in Jingsha, Hubei,and their photo-thermo-growing properties

Hydrothermal carbonization pretreatment makes a remarkable difference in activation of rice and lettuce in food waste

Cooked rice and the vegetables like lettuce are common kitchen waste,which are carbonaceous materials and have the potential as feedstock for the production of activated carbon.Cooking is similar to hydrothermal treatment(HTC),which might impact the subsequent activation of kitchen waste.In this study,the HTC of lettuce,rice,or their mixture and the activation of the resulting hydrochars were conducted.The results indicated that cross-polymerization between the N-containing organics from lettuce and the sugar derivatives from rice took place in their co-HTC,which significantly increased the hydrochar yield.Activation of the hydrochar from the coHTC generated the AC with a yield of 2 times that from direct activation of mixed lettuce/rice.However,the coHTC facilitated aromatization,reducing reactivity with K2C2O4in activation and producing the AC with main micropores and low specific surface area.Activation of the hydrochar from HTC of rice followed the above trend,while that from lettuce was the opposite.The organics in lettuce were thermally unstable and could not undergo sufficient aromatization.The activation of hydrochar from HTC of lettuce thus generated the AC with the lowest yield,but the highest specific surface area(1684.9 m2/g),abundant mesopores,and superior capability for adsorption of tetracycline.However,the environmental impacts and energy consumption for the production of AC from the hydrochar of lettuce were higher than that from hydrochar of co-HTC.

Unique Ergodicity for Zero-entropy Dynamical Systems with the Approximate Product Property

We show that for every topological dynamical system with the approximate product property, zero topological entropy is equivalent to unique ergodicity. Equivalence of minimality is also proved under a slightly stronger condition. Moreover, we show that unique ergodicity implies the approximate product property if the system has periodic points.

Approximation of the Shannon Capacity Via Matrix Cone Programming

This paper proposes a novel formulation using the matrix cone programming to compute an upper bound of the Shannon capacity of graphs,which is theoretically superior to the Lovász number.To achieve this,a sequence of matrix cones is constructed by adding certain co-positive matrices to the positive semi-definite matrix cones during the matrix cone programming.We require the sequence of matrix cones to have the weak product property so that the improved result of the matrix cone programming remains an upper bound of the Shannon capacity.Our result shows that the existence of a sequence of suitable matrix cones with the weak product property is equivalent to the existence of a co-positive matrix with testable conditions.Finally,we give some concrete examples with special structures to verify the existence of the matrix cone sequence.