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1.
《Journal of dairy science》2022,105(8):7097-7110
Biotin (B8), folate (B9), and vitamin B12 (B12) are involved in several metabolic reactions related to energy metabolism. We hypothesized that a low supply of one of these vitamins during the transition period would impair metabolic status. This study was undertaken to assess the interaction between B8 supplement and a supplementation of B9 and B12 regarding body weight (BW) change, dry matter intake, energy balance, and fatty acid (FA) compositions of colostrum and milk fat from d ?21 to 21 relative to calving. Thirty-two multiparous Holstein cows housed in tie stalls were randomly assigned, according to their previous 305-d milk yield, to 8 incomplete blocks in 4 treatments: (1) a 2-mL weekly i.m. injection of saline (0.9% NaCl; B8?/B9B12?); (2) 20 mg/d of dietary B8 (unprotected from ruminal degradation) and 2-mL weekly i.m. injection of 0.9% NaCl (B8+/B9B12?); (3) 2.6 g/d of dietary B9 (unprotected) and 2-mL weekly i.m. injection of 10 mg of B12 (B8?/B9B12+); (4) 20 mg/d of dietary B8, 2.6 g/d of dietary B9, and 2-mL weekly i.m. injection of 10 mg of B12 (B8+/B9B12+) in a 2 × 2 factorial arrangement. Colostrum was sampled at first milking. and milk samples were collected weekly on 2 consecutive milkings and analyzed for FA composition. Body condition score and BW were recorded every week throughout the trial. Within the first 21 d of lactation, B8?/B9B12+ cows had an increased milk yield by 13.5% [45.5 (standard error, SE: 1.8) kg/d] compared with B8?/B9B12? cows [40.1 (SE: 1.9)], whereas B8 supplement had no effect. Even though body condition score was not affected by treatment, B8?/B9B12+ cows had greater BW loss by 24 kg, suggesting higher mobilization of body reserves. Accordingly, milk de novo FA decreased and preformed FA concentration increased in B8?/B9B12+ cows compared with B8?/B9B12? cows. In addition, cows in the B8+/B9B12? group had decreased milk de novo FA and increased preformed FA concentration compared with B8?/B9B12? cows. Treatment had no effect on colostrum preformed FA concentration. Supplemental B8 decreased concentrations of ruminal biohydrogenation intermediates and odd- and branched-chain FA in colostrum and milk fat. Moreover, postpartum dry matter intake for B8+ cows tended to be lower by 1.6 kg/d. These results could indicate ruminal perturbation caused by the B8 supplement, which was not protected from rumen degradation. Under the conditions of the current study, in contrast to B8+/B9B12? cows, B8?/B9B12+ cows produced more milk without increasing dry matter intake, although these cows had greater body fat mobilization in early lactation as suggested by the FA profile and BW loss. 相似文献
2.
Liu Yang Pengfei Yu Wenyuan Li Fengliang Cao Xin Jin Sheng Xue Xianglong Zhang Tingwei Zhang Mingbo Wu Wenting Wu 《American Institute of Chemical Engineers》2022,68(9):e17760
Hydrogen peroxide (H2O2) has been listed as one of the 100 most important chemicals in the world. However, huge amount of residual H2O2 is hard to timely decomposed into O2 and H2O under acidic condition, easily resulting in explosion hazard. Here, we reported a core–shell structure catalyst, that is graphene with Co N structure encapsulated Co nanoparticles. Co N graphene shell serves as the active site for the H2O2 decomposition, and Co core further enhance this decomposition. Benefiting from it, the H2O2 decomposition were close to 100% after 6 cycles without pH adjustment, which increased 6 orders of magnitude compared with no catalyst. At the same time, the O2 generation reached 99.67% in 2 h with little metal leaching, and ·OH has been greatly inhibited to only 0.08%. This work can cleanly remove H2O2 with little deep oxidation and protect the process of H2O2 utilization to achieve a safer world. 相似文献
3.
《Ceramics International》2022,48(24):36802-36813
X-type samarium-cadmium co-substituted hexaferrite with compositions Ba2-xSmxCo2CdyFe28-yO46 (0.00 ≤ x ≤ 0.08, and 0 ≤ y ≤ 0.4) were prepared at 1340 °C using a simple heat treatment technique. All heated samples were characterized using FTIR, XRD, SEM, VSM, M?ssbauer, and low-frequency dielectric measurements. XRD analysis of prepared samples shows the formation of X as a major phase along with hematite. The MS value varied from 67.01 Am2/kg to 50.43 Am2/kg; whereas the Hc value changed from 2.95 kA/m to 6.17 kA/m, A high value of MS (67.01 Am2/kg) is observed in the pure sample, and a very low value of Hc (2.95 kA/m) is observed for x = 0.06, y = 0.3 compositions, but Mr/Ms < 0.5 confirm the multi-domain nature of prepared hexaferrites. Hysteresis loops of all samples are narrow, and confirmed that formed samples belong to magnetically soft. Mössbauer spectra of the three samples (S1, S3, and S5) show the existence of doublets. Significantly low values of coercivity, retentivity, and loss tangent in Sm–Cd substituted samples signified those prepared materials can be used to design electromagnets, transformer cores, electric motors, and maybe a potential candidate for lossless low-frequency applications. 相似文献
4.
Floating treatment wetlands (FTWs) use plants’ roots for water quality improvement. The plants are supported by a buoyant structure deployed at the water surface. The roots form a porous zone beneath the structure and remove pollutants carried in suspension through filtering, absorption and uptake. This paper used CFD simulation to model FTWs arranged in series and spanning the channel width and to study the effects of root length and spacing between FTWs on flow distribution and mass removal. The root zone was modelled as a porous media, and removal was computed using first-order decay, for which a range of removal constants was tested. Longer roots increased the reactive volume of the root zone, which increased the fraction of pollutant inflow entering the FTWs. Increasing the distance between FTWs allowed greater mixing between water that went through and beneath the upstream FTW. This increased the concentration entering each FTW, which enhanced mass removal per FTW. However, a larger distance between FTWs reduced the number of FTWs in the channel, reducing the reactive volume. In the tradeoff between mixing and reactive volume, the reactive volume was more important, such that total removal in the channel increased with longer roots and more units of FTW (shorter gap distance). However, removing the gap entirely was detrimental, as FTWs in series removed more mass than a continuous FTW of same volume. This study points to two design recommendations for FTWs in series. First, if resources for building FTWs are not limiting, but the channel length is, it is preferable to prioritize higher reactive volume (shorter gap distance) to achieve maximum removal per channel length. Second, if resources for FTWs are limiting, but channel length is not, it is better to place the FTWs with a longer gap distance, preferably along enough to allow mixing over the full depth between FTWs, as this will achieve maximum removal per FTW. 相似文献
5.
6.
《International Journal of Hydrogen Energy》2022,47(36):16121-16131
Ammonia is considered as a promising hydrogen or energy carrier. Ammonia absorption or adsorption is an important aspect for both ammonia removal, storage and separation applications. To these ends, a wide range of solid and liquid sorbents have been investigated. Among these, the deep eutectic solvent (DES) is emerging as a promising class of ammonia absorbers. Herein, we report a novel type of DES, i.e., metal-containing DESs for ammonia absorption. Specifically, the NH3 absorption capacity is enhanced by ca. 18.1–36.9% when a small amount of metal chlorides, such as MgCl2, MnCl2 etc., are added into a DES composed of resorcinol (Res) and ethylene glycol (EG). To our knowledge, the MgCl2/Res/EG (0.1:1:2) DES outperforms most of the reported DESs. The excellent NH3 absorption performances of metal–containing DESs have been attributed to the synergy of Lewis acid–base and hydrogen bonding interactions. Additionally, good reversibility and high NH3/CO2 selectivity are achieved over the MgCl2/Res/EG (0.1:1:2) DES, which enables it to be a potential NH3 absorber for further investigations. 相似文献
7.
《International Journal of Hydrogen Energy》2022,47(19):10736-10746
This study demonstrates the successful development of hybrid mesoporous siliceous phosphotungstic acid (mPTA-Si) and sulfonated poly ether ether ketone (SPEEK) as a proton exchange membrane with a high performance in hydrogen proton exchange membrane fuel cells (PEMFC). SPEEK acts as a polymeric membrane matrix and mPTA-Si acts as the mechanical reinforcer and proton conducting enhancer. Interestingly, incorporating mPTA-Si did not affect the morphological aspect of SPEEK as dense membrane upon loading the amount of mPTA-Si up to 2.5 wt%. The water uptake reduced to 14% from 21.5% when mPTA-Si content increases from 0.5 to 2.5 wt% respectively. Meanwhile, the proton conductivity increased to 0.01 Scm?1 with 1.0 wt% mPTA-Si and maximum power density of 180.87 mWcm?2 which is 200% improvement as compared to pristine SPEEK membrane. The systematic study of hybrid SP-mPTA-Si membrane proved a substantial enhancement in the performance together with further improvement on physicochemical properties of parent SPEEK membrane desirable for the PEMFC application. 相似文献
8.
9.
Xuejie Li Yaqing Wen Jian Zhang Dongyun Ma Jie Zhang Yanxia An Xiaoyan Song Xiujuan Ren Weifeng Zhang 《International Journal of Food Science & Technology》2022,57(3):1544-1553
The effects of non-thermal plasma (NTP) on the physicochemical properties of wheat flour and the quality of fresh wet noodles ( FWN) were investigated. The results showed that NTP effectively decreased the total plate count (TPC), yeast and mould count (YMC) and Bacillus spp. in wheat flour. Wet gluten contents and the stability time reached the maximum when treated for 20 s. The viscosity of starch increased significantly after treatment due to the increased of damaged starch. The contents of secondary structure were altered to some extent, which was because that the ordered network structure of gluten protein broken. Furthermore, compared with the control, texture properties of FWN were enhanced significantly at 20 s, and the darkening rate of FWN was greatly inhibited due to the low polyphenol oxidase (PPO) activity. Consequently, the most suitable treatment was 500 W for 20 s, providing a basis for the application of NTP in flour products. 相似文献
10.