The critical role of Zr in controlling the activity of Pd/Beta on the hydrogenation of phenol to cyclohexanone

The promoting effect of zirconium addition on Pd/Beta catalysts has been investigated in the selective hydrogenation of phenol to cyclohexanone in the aqueous phase. The activity of the catalyst in the reaction was greatly improved by introducing Zr atoms into the framework of H-Beta zeolite. An important synergy between the Zr species and Pd, affecting the Pd dispersion state on the support, has been observed. The modification of the support with Zr^(4+) improves the Lewis/Brφnsted acid ratio of the catalyst, suppressing the further transformation of cyclohexanone. The kinetics of Pd/Zr-Beta catalyst showed high selectivity to cyclohexanone. The catalytic results showed that the Pd/Zr-Beta had the best catalytic performance at the desired temperature of 80℃ for 5 h.

A real-time performance improvement method for composite time scale

The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern society.The improvement of CTS’s real-time performance will improve its stability,which strengths related applications’performance.Aiming at this goal,a method achieved by determining the optimal calculation interval and accelerating adjustment stage is proposed in this paper.The determinants of the CTS’s calculation interval(characteristics of the clock ensemble,the measurement noise,the time and frequency synchronization system’s noise and the auxiliary output generator noise floor)are studied and the optimal calculation interval is obtained.We also investigate the effect of ensemble algorithm’s initial parameters on the CTS’s adjustment stage.A strategy to get the reasonable initial parameters of ensemble algorithm is designed.The results show that the adjustment stage can be finished rapidly or even can be shorten to zero with reasonable initial parameters.On this basis,we experimentally generate a distributed CTS with a calculation interval of 500 s and its stability outperforms those of the member clocks when the averaging time is longer than1700 s.The experimental result proves that the CTS’s real-time performance is significantly improved.

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.

Quality, fatty acid composition and oxidation stability of ten cold-pressed seed oils

Cold-pressed oils from six herb plant seeds and four woody plant seeds were analyzed and compared for their quality characteristics such as oil, crud protein, shell, and moisture content, fatty acid （FA） compositions and oxidation stability. Results showed that walnut kernel contained the greatest amount of seed oil and safflower seed contained the lowest. Safflower, pumpkin, hemp, camellia and peony seeds had high shell content, their kernel oil content significantly increased after shelling. These oils had significant differences （p〈0.01） in levels of fatty acids and the ratio of n-6：n-3 fatty acids. Camellia, safflower, and flax seed oil contained the highest oleic acid, linoleic acid, and a-linolenic acid respectively. Hemp seed oil was observed in a 3.53：1 ratio of n-6 and n-3 fatty acids. All these ten oils were obviously different in moisture and volatile content, acid value, peroxide value and induction period （IP） （p〈0.01）. IP of peony seed oil was lowest （0.94 h） and almond oil was the highest （14.10 h）. IP of oils negatively correlated with polyunsaturated fatty acids content ^=-0.664, p=0.036）. These studies of ten cold-pressed oils may provide better explanation for their potential health benefits and further developing their commercial value.

Adsorption behavior of free fatty acids and micro-components in rapeseed oil on alkaline microcrystalline cellulose

Alkaline microcrystalline cellulose (AMC) was used as adsorption agent in deacidification in this paper. Changes of isothermal adsorption of free fatty acids (FFA) and micro-components (α-tocopherol and β-sitosterol) in rapeseed oil on AMC were investigated. The results showed that difference in initial micro-component contents would not change adsorption characteristics of AMC to FFA. Adsorption characteristics were always as the following: Langmuir equation was more suitable to static adsorption process of AMC to FFA than Freundlich equation; moderate temperature (30-40oC) was advantageous to adsorption; adsorption was a preferential one. The highest retention rate of α-tocopherol and β-sitosterol during absorptive deacidification by AMC were 99.5% and 91.5% respectively. Therefore, AMC was suitable for adsorption deacidification application of rapeseed oil.

MCM-22 zeolite-based system to produce jet fuel from the 1-hexene oligomerization

The oligomerization of light olefins is an alternative for generating clean liquid fuels.In this study,the MCM-22 zeolite featuring a partially disordered layered structure with framework combined 10 membered ring(10 MR)was discussed for 1-hexene oligomerization.MCM-22 and Y zeolite were compared to investigate the influences of the framework and acidity strength on the activity and yield in the 1-hexene oligomerization.The results indicated that the MCM-22 zeolite was an efficient catalyst for oligomerization compared to Y zeolite.The MCM-22 zeolite was characterized in detail by NMR,Py-FTIR,and TG analyses.The catalytic performance and deactivation properties of MCM-22 zeolite in the oligomerization reaction of 1-hexene were investigated.Structure-activity relationships were established through the kinetic study.Although the density of strong acid sites was essential for the oligomerization of 1-hexene,the presence of low pressure was also necessary for the formation of dimers.Thus,MCM-22 zeolite demonstrates a substantial improvement in initial conversion and catalyst lifespan for 1-hexene oligomerization.

DEAD-box helicase 17(DDX17)protects cardiac function by promoting mitochondrial homeostasis in heart failure

DEAD-box helicase 17(DDX17)is a typical member of the DEAD-box family with transcriptional cofactor activity.Although DDX17 is abundantly expressed in the myocardium,its role in heart is not fully understood.We generated cardiomyocyte-specific Ddx17-knockout mice(Ddx17-cKO),cardiomyocyte-specific Ddx17 transgenic mice(Ddx17-Tg),and various models of cardiomyocyte injury and heart failure(HF).DDX17 is downregulated in the myocardium of mouse models of heart failure and cardiomyocyte injury.Cardiomyocyte-specific knockout of Ddx17 promotes autophagic flux blockage and cardiomyocyte apoptosis,leading to progressive cardiac dysfunction,maladaptive remodeling and progression to heart failure.Restoration of DDX17 expression in cardiomyocytes protects cardiac function under pathological conditions.Further studies showed that DDX17 can bind to the transcriptional repressor B-cell lymphoma 6(BCL6)and inhibit the expression of dynamin-related protein 1(DRP1).When DDX17 expression is reduced,transcriptional repression of BCL6 is attenuated,leading to increased DRP1 expression and mitochondrial fission,which in turn leads to impaired mitochondrial homeostasis and heart failure.We also investigated the correlation of DDX17 expression with cardiac function and DRP1 expression in myocardial biopsy samples from patients with heart failure.These findings suggest that DDX17 protects cardiac function by promoting mitochondrial homeostasis through the BCL6-DRP1 pathway in heart failure.

Physicochemical properties and volatile components of hempseed oils in Bama region

A comparison study has been performed in hempseed oils (HSO) extracted from different cultivars in Bama region. Squeezing properties, chemical compositions, thermal stability and flavor profile of pressed HSO were determined in this study. Results indicated that there were no significant differences in crude fat, protein, fiber of different hempseeds and fatty acid composition in HSOs. Hempseeds with small size and dark-colored peel have lower squeezing oil yield than big ones. Average content of total phytosterol, tocopherol and phenol in HSO from small seeds were 872.0 mg/100 g, 124.1 mg/100 g and 15.5 mg SA/100 g respectively. Thermal oxidation by differential scanning calorimetry (DSC) revealed three step oxidation of HSO with mean onset and oxidation temperature at 124oC and 135-315oC. Oxidation temperature of HSO from small seeds was higher than that from big seeds (big size and light-colored peel). Main volatile ingredients in HSO contained 11 kinds of monoterpene and 7 kinds of sesquiterpene. Volatile terpene content in HSO from small seeds was nearly 30% higher than that of big seeds. Quality of HSO with different peel feature has significant difference in squeezing yield, thermal stability and volatile flavors. This work may be useful to produce high quality hempseed oils through quality evaluation.

Non-covalent interaction between almond protein and sinapic acid: impact on protein structure and antioxidant activity

Plant phenolic acids are good sources of antioxidants and sinapic acid(SA)is one of them that can be applied in protein-based food system.However,little research is available regarding interactions between almond protein(AP)and SA.In this study,structure-affinity interaction between SA and AP,structure and antioxidant activity of proteins were investigated.Different mathematical models showed that Ka of binding SA and AP were 3.27×10^4 L/mol and 3.08×10^4 L/mol.CD(Circular dichroism)spectroscopy and FT-IR(Fourier transform infrared)spectroscopy showed that the amount of random coil andα-helix decreased whileβ-sheet increased in AP-SA complex.In combination,the interaction model of AP-SA complex was static quenching and attributed to hydrophobic interaction.Further,AP-SA complex exerted better DPPH radical scavenging ability(36.97±0.78%),ABTS+radical scavenging ability(47.26±0.45%),and higher ORAC value(2.41±0.23 M trolox/g)compared to AP.In the further,SA can be applied in protein matrix to improve film stability,gel strength and restraining fat oxidation degradation.

Preparation and characterization of nanocellulose from rapeseed hull

Rapeseed hull, a by product in rapeseed processing, deserves deep research for extensive application to promote its limited value at present. The aim of this study was to explore utilization of rapeseed hull as a source of raw material for nanocellulose. On the basis of pretreatment with sodium hydroxide solution and peroxide solution, nanocellulose from rapeseed hull(NRH) was prepared by sulfuric acid hydrolysis. Samples of different pretreatment stages were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, infrared spectrum and thermo-gravimetric analysis. Results showed that sodium hydroxide solution and peroxide solution pretreatment could significantly increase cellulose content of the material(p < 0.05). NRH prepared by sulfuric acid hydrolysis was of short rod structure, 50-250 nm in length with diameter of 5-25 nm. It had a typical type of celluloseⅠcrystal with 64.4% crystallinity. Initial thermal decomposition temperature of NRH was the lowest among all samples. NRH was expected to be applied in biodegradable composites. Therefore, this work will provide reference for further utilization of rapeseed hull as a low-cost source of nanocellulose.

Effects of microwave pretreatment on oxidation of pressed rapeseed oil during accelerated storage

To investigate advantages of microwave pretreatment for oil storage, oxidative stability of pressed rapeseed oil with microwave pretreatment (M-RO) was evaluated, while pressed rapeseed oil (RO) and RO with 200 ppm tertiary butylhydroquinone added (T-RO) were used for comparison. Oil samples were collected after accelerated storage at 60oC in dark for 0-32 d. A total of 37 oxidized volatile compounds were identified and 9 typical key compounds were quantified by solid-phase microextraction gas chromatography/mass spectrometry (HS-SPME-GC/MS). Correlation analysis showed that lipid oxidation parameters and induction time (IP) had significant association with typical indicators of volatile oxidized compounds. Hexanal and (E,E)-2,4-heptadienal were most suitable for differentiating RO sample at different storage times while 1-hexanol, 1-heptanal and (E)-2-octenal were suitable for T-RO sample. To M-RO sample, 5 substances described above together can provide a guide for monitoring lipid oxidation. M-RO has better oxidation resistance than RO, with advantage of 4 d in accelerated conditions both in sensory evaluation and PCA analysis. However, it still produces more volatile oxidized compounds and has higher peroxide value (PV) and p-anisidine value (p-AV) than T-RO sample at any sampling point. Anti-oxidation efficiency of rapeseed oil can be promoted via microwave pretreatment. This work provid new clues of benefits about microwave pretreatment in oil storage.

Microwave pre-treatment improved antioxidant activities of Brassica seeds, cold-pressed oil and cake

In order to analyze microwaving effects on antioxidant activities of seeds, oil, pressed-cake, and defatted-meal in cold pressed process, 3 species of Brassica (B. napus, B. juncea and B. rapa) seeds were treated in microwave oven at 560 W for 7 min. Antioxidant activities of samples from untreated seeds and 7-min microwaved seeds were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, ferric reducing antioxidant power (FRAP) method, and β-carotene bleaching (BCB) test. Results showed that microwave pre-treatment increased free radical scavenging activities (RSA), total antioxidant activities (TAA), and coefficient of antioxidant activity (CAA). Antioxidant activities of 7-min microwave pre-treated cold pressed oil were significantly higher than those of untreated ones due to increasing canolol content. Furthermore, microwave enhanced antioxidant activities of B. napus seeds more effectively than those of the other 2 species. This research provided better understanding for microwave pre-treatment application in antioxidant activity improvement of cold pressed oil.

Bioactive compounds and antioxidant activities of cold-pressed seed oil

Ten cold-pressed oil from 6 herb plant seeds （sesame, fax, saffower, pumpkin, tomato and hemp） and 4 woody plant seeds （camellia, almond, walnut and peony） were analyzed to determine bioactive compounds content, including tocopherols, phytosterols and phenolics, as well as their antioxidant activities. Total tocopherols content ranged from 161.11 mg/kg in camellia seed oil to 1,072.51 mg/kg in tomato seed oil. Tomato seed oil had the highest total phytosterols （708.89 mg/100 g） and phenolics content （20.27 mg SAE/100 g）,whereas, saffower seed oil has the lowest total phytosterols （173.75 mg/100g） and walnut kernel oil contained the lowest phenolics （2.32 mg SAE/100 g）, respectively. Tomato seed oil exhibited the strongest ferric-reducing antioxidant power （FARP, 311.36 μmol/100 g） and 2,2-diphenyl-1-picrylhydrazyl （DPPH） radical scavenging activity （56.40 μmol/100 g）, while camellia seed oil had the lowest FRAP value （34.83 μmol/100 g） and fax seed oil had the lowest DPPH value （2.75 μmol/100 g）. Correlation coeffcient was determined as 0.647 and 0.863 between FRAP value and total tocopherols and phenolics, and 0.673 and 0.711 between DPPH value and total tocopherols and phenolics （p 〈 0.05）, respectively. This result indicated the antioxidant activities （FRAP and DPPH） were highly correlated with total tocopherols and phenolics content of oil. This study will be very useful for comprehensive utilization of all 10 cold-press oils.

Conversion of mouse fibroblasts into oligodendrocyte progenitor-like cells through a chemical approach

Transplantation of oligodendrocyte progenitor cells (OPCs) is a promising way for treating demyelinating diseases. However, generation of scalable and autologous sources of OPCs has proven difficult. We previously established a chemical condition M9 that could specifically initiate neural program in mouse embryonic fibroblasts. Here we found that M9 could induce the formation of colonies that undergo mesenchymal-to-epithelial transition at the early stage of reprogramming. These colonies may represent unstable and neural lineage-restricted intermediates that have not established a neural stem cell identity. By modulating the culture signaling recapitulating the principle of OPC development, these intermediate cells could be reprogrammed towards OPC fate. The chemical-induced OPC-like cells (ciOPLCs) resemble primary neural stem cell-derived OPCs in terms of their morphology, gene expression, and the ability of self-renewal. Upon differentiation, ciOPLCs could produce functional oligodendrocytes and myelinate the neuron axons in vitro, validating their OPC identity molecularly and functionally. Therefore, our study provides a non-integrating approach to OPC reprogramming that may ultimately provide an avenue to patient-specific cell-based or in situ regenerative therapy.

The variable structure controller design for a class of nonlinear uncertain systems based on robust observer

The variable structure controller is designed for a class of nonlinear uncertain time-delay system by using robust observer, and incorporating H-infinity control technique, the controller can guarantee the H-infinity performance of sliding mode dynamics and satisfy the reaching condition, which also does not require uncertainties to satisfy matching condition and linear boundary condition. The simulation example is given to illustrate the method.

Promotional effect of Mn doping on Ru/layered MCM-49 catalysts for the conversion of Levulinic acid to γ-Valerolactone

Selective hydrogenation of Levulinic acid(LA)toγ-Valerolactone(GVL)is an important reaction to produce high value-added chemicals and fuels but remains a big challenge.Herein we reported a Ru/zeolite catalyst with Mn promotion,which exhibited excellent catalytic performance(yield:98%)towards LA to GVL.The intrinsic activity(TOF)also increased obviously with the Mn addition.The particle size of Ru gradually decreased with the increase of Mn loading and a strong interaction between Ru and support was observed for the Ru-Mn/MCM-49 catalyst.The addition of Mn not only offered a good dispersion of Ru species on MCM-49,but also increased the L/B ratio of the catalyst,thereby contributing to the high GVL selectivity.High dispersed Ru sites were the intrinsic active sites of the catalyst verified by the in-situ experimental studies.The dissociation of the reactants was significantly enhanced,resulting in higher catalytic activity.

Retrospective study on Professor Zhongying Zhou's experience in Traditional Chinese Medicine treatment on diabetic nephropathy

OBJECTIVE:To study and analyze the etiology and pathogenesis,diagnosis and prescription for cases of diabetic nephropathy(DN) treated by Professor Zhongying Zhou(Prof.Zhou) with the help of dada mining technique,so as to inherit his clinical experience and academic thoughts.METHODS:After pretreatment of the medical record information,statistical software SPSS 13.0 was used to analyze and process the standardized data using the descriptive analysis,cluster analysis and association rules.RESULTS:Ninety-four entries derived from Traditional Chinese Medicine(TCM) four-diagnostic information were selected.Through data mining,the highest frequency was yellow-thin-greasy tongue coating,followed by dark tongue,and then by thready-slippery pulse.The main self-conscious symptoms were limb numbness,dry mouth,frequent micturition,etc.With respect to pathogenesis,the etiology related to kidney reached 73.46%.The frequency of pathological factors for deficiency,blood stasis,heat,dampness,phlegm and dryness were 137.65%,80.25%,78.40%,48.77%,21.60%,and 14.20% respectively.A total of 236 kinds of herbs were used 2913 person times,averaging 17.98 herbs per prescription.CONCLUSION:The pathological location of DN is in the kidney.The pathogenesis of the disease is deficiency in origin and excess in superficiality,the former of which include deficiency of the liver and kidney,and deficiency of both Qi and Yin.The main pathological factors are blood stasis,heat,dampness,phlegm,and dryness;and they act upon each other to form the complex pathogenesis in terms of blood stasis-heat,dampness-heat,phlegm-heat,and dryness-heat.All the above factors are always crucial in the aggravation of DN throughout the whole course of its pathological evolution.

Iridium(I)-catalyzed deoxgenation of fluoroalkylsulfoxides with dimethyl diazomalonate to access fluoroalkylthioethers

A new method for the preparation of fluoroalkylthioethers including trifluoromethylthioether and difluoromethylthioether by iridium(Ⅰ)-catalyzed deoxgenation of fluoroalkylsulfoxides with dimethyl diazomalonate was developed.In the reaction system,dimethyl diazomalonate was used as reducing reagent and the corresponding fluoroalkylthioethers were produced through oxygen atom transfer from fluoroalkylsulfoxides to diazomalonate.The protocol featuring effective oxygen atom transfer,mild reaction conditions and good functional groups tolerance offers an alternative strategy for the synthesis of fluoroalkylthioethers.