Research progress of CO_(2)oxidative dehydrogenation of propane to propylene over Cr-free metal catalysts

CO_(2)-assisted oxidative dehydrogenation of propane(CO_(2)-ODHP)is an attractive strategy to offset the demand gap of propylene due to its potentiality of reducing CO_(2)emissions,especially under the demands of peaking CO_(2)emissions and carbon neutrality.The introduction of CO_(2)as a soft oxidant into the reaction not only averts the over-oxidation of products,but also maintains the high oxidation state of the redox-active sites.Furthermore,the presence of CO_(2)increases the conversion of propane by coupling the dehydrogenation of propane(DHP)with the reverse water gas reaction(RWGS)and inhibits the coking formation to prolong the lifetime of catalysts via the reverse Boudouard reaction.An effective catalyst should selectively activate the C–H bond but suppress the C–C cleavage.However,to prepare such a catalyst remains challenging.Chromium-based catalysts are always applied in industrial application of DHP;however,their toxic properties are harmful to the environment.In this aspect,exploring environment-friendly and sustainable catalytic systems with Cr-free is an important issue.In this review,we outline the development of the CO_(2)-ODHP especially in the last ten years,including the structural information,catalytic performances,and mechanisms of chromium-free metal-based catalyst systems,and the role of CO_(2)in the reaction.We also present perspectives for future progress in the CO_(2)-ODHP.

Two-dimensional Nb_(3)Cl_(8)memristor based on desorption and adsorption of O_(2)molecules

As a novel two-dimensional(2D)semiconductor material with biocompatibility and ferromagnetic properties,Nb_(3)Cl_(8)exhibits a great prospect in the field of implantable electrical equipment.In this work,the effects of the light illumination and the gate voltage on the desorption of O_(2)molecules from Nb_(3)Cl_(8)were systemically investigated via the in situ electrical transport characterization in the vacuum environment.The experimental results showed that the light illumination and the negative gate voltage could enhance the desorption of oxygen molecules while the positive gate voltage could promote the re-adsorption of O_(2).The multi-bit storage function was demonstrated via adjusting the p-doping effect caused by oxygen adsorption.A novel mechanism of optical writing and electrical erasing in this Nb_(3)Cl_(8)memristor was proposed,which was in coincidence with the expected results of the control experiment in air.These results shed light on the great potential of Nb_(3)Cl_(8)in high-density data storage,neuromorphic,wearable applications and implantable devices application.

Genetic polymorphism analyses of a novel panel of 19 X-STR loci in the Chinese Uygur ethnic minority

The population genetic data and forensic parameters of 19 X-chromosome short tandem repeat （X-STR） loci in Chinese Uygur ethnic minority are presented. These loci were detected in a sample of 233 （94 males and 139 females） unrelated healthy individuals. We observed 238 alleles at the 19 X-STR loci, with the corresponding gene frequencies spanning the range from 0.0021 to 0.5644. After Bonferroni correction （P〉0.0026）, there were no signif- icant deviations from Hardy-Weinberg equilibrium. The cumulative power of discrimination in females and males, and the probability of exclusion of the 19 X-STR loci were 0.999 999 999 999 999 999 998 091,0.999 999 999 999 966, and 0.999 999 986 35, respectively. The cumulative mean exclusion chance was 0.999 999 992 849 in deficiency cases, 0.999 999 999 999 628 in normal trios, and 0.999 999 998 722 in duo cases. The high value of the forensic parameters mentioned above revealed that the novel panel of 19 loci had important values for forensic applications in the LJygur group.

Genetic distribution and forensic evaluation of multiplex autosomal short tandem repeats in the Chinese Xinjiang Mongolian group

To further enrich the genetic data of the Chinese Xinjiang Mongolian group,the genetic distribution and forensic parameters of 19 autosomal short tandem repeats(STRs)were investigated.Altogether,249 alleles were observed in these 19 STRs.The mean values of the polymorphism information content(PIC),match probability(MP),discrimination power(DP),and probability of exclusion(PE)for these 19 STRs were 0.7775,0.0699,0.9301,and 0.6085,respectively.Additionally,the cumulative DP and PE values obtained in the Mongolian group were 0.999 999 999 999 999 999 999 995 67 and 0.999 999 992 163,respectively.

The Effects of Ground and Treadmill Running on Energy Metabolism and Muscle Contractile Properties:A Randomized Cross-Over Study

Purpose This study aimed to compare the effects of ground and treadmill running on energy metabolism and muscle con-tractile properties,providing a basis for the general public to choose running venues.Methods Ten male college students(age,20.10±1.53 years;height,176.20±5.49 cm;weight,72.14±8.25 kg;body fat percent,12.41%±4.65%)were recruited in this study.Energy expenditure(EE)was measured using the accelerometer(GT9X)combined with specific estimation equations.Average heart rate(HR)was measured using a heart rate band(Polar).Muscle contractile properties were assessed by measuring muscle displacement(Dm)and contraction velocity(Vc)using tensiomyography(TMG-S1).Blood glucose(Glu)and lactate(Lac)were measured by portable devices(eB-G and Lactate Scout).The running speed was 9 km/h and the duration was 25 min.Two-way ANOVA(protocol×time)was used to analyze the effect of running protocols on energy metabolism and muscle contractile properties.Results EE of treadmill running was significantly higher than EE of ground running(protocol main effect,P<0.001),and HR of treadmill running was significantly higher than that of ground running in the first testing time(protocol simple effect,P=0.026;protocol×time interaction P=0.043).The decrease in Dm of the rectus femoris after treadmill running was significantly higher than that of ground running(protocol main effect,P=0.009).The interaction of different running protocols and testing times on Lac was significant(P=0.025),but all results of the simple effects analysis were not statisti-cally significant(P>0.05).Conclusion Our study found a difference in energy expenditure between treadmill and ground running at 9 km/h with duration of 25 min.In addition,treadmills are more likely to cause a decrease in muscle displacement distance of the rectus femoris measured after exercise than ground running.Future studies are needed to further investigate whether the differences are induced by internal metabolism or the environmental conditions of running.