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The manganese based lithium ion sieve H1.6Mn1.6O4 is regarded as a promising adsorbent for recovering lithium from salt-lake brines. However, the poor recycle stability caused by the dissolution of manganese hinders its industrial application. In this work, the Co-doped H1.6CoxMn1.6-xO4 ion sieve with enhanced cycling performance for Li + adsorption was prepared through hydrothermal synthesis. The results of XRD and SEM indicated that Co-doping did not affect the spinel crystal structure of Li1.6Mn1.6O4 and a micro array structure was obtained. The cooperative effect of Co-doping and the micro array structure morphology on the Li + adsorption performance was investigated. Compared with H1.6Mn1.6O4(23.53 mg/g), the adsorption capacity of H1.6Co0.16Mn1.44O4 reached 29.95 mg/g. Also, H1.6Co0.16Mn1.44O4 showed excellent cycling performance that the Li + adsorption capacity maintained over 88% and the dissolution rate of manganese was below 2% after five cycles. The Co-doped H1.6CoxMn1.6-xO4 ion sieves show the prospects to be employed for the Li + extraction from aqueous lithium resources.

Clostridioides difficile is considered an urgent threat to human health by the US Centers for Disease Control and Prevention. In recent years, C. difficile has been reported increasingly as a cause of gastrointestinal disease in children, and the prevalence of hospital-acquired C. difficile infection and community-acquired CDI in children is increasing.To perform a systematic review and meta-analysis of risk factors for CDI in children.MEDLINE/PubMed, EMBASE, Web of Science, Scopus, OVID, China National Knowledge Infrastructure, Wanfang (Chinese), SinoMed (Chinese) and Weipu (Chinese) were searched from inception to 12In total, 25 observational studies were included in the analysis. Prior antibiotic exposure [OR 1.93, 95% confidence interval (CI) 1.25-2.97], prolonged hospitalization (OR 14.68, 95% CI 13.24-16.28), history of hospitalization (OR 3.67, 95% CI 1.91-7.06), gastric acid suppressants (OR 1.96, 95% CI 1.41-2.73), male gender (OR 1.18, 95% CI 1.05-1.32), neoplastic disease (OR 3.40, 95% CI, 2.85-4.07), immunodeficiency (OR 4.18, 95% CI 3.25-5.37), solid organ transplantation (OR 4.56, 95% CI 3.95-5.27) and enteral feeding (OR 2.21, 95% CI 1.05-4.62) were associated with increased risk of CDI.This systematic review and meta-analysis provides further evidence for the susceptibility factors of CDI to improve clinicians' awareness of CDI, and prevent C. difficile-associated diarrhoea in children.

To investigate the influences of dietary riboflavin (RF) addition on nutrient digestion and rumen fermentation, eight rumen cannulated Holstein bulls were randomly allocated into four treatments in a repeated 4 × 4 Latin square design. Daily addition level of RF for each bull in control, low RF, medium RF and high RF was 0, 300, 600 and 900 mg, respectively. Increasing the addition level of RF, DM intake was not affected, average daily gain tended to be increased linearly and feed conversion ratio decreased linearly. Total tract digestibilities of DM, organic matter, crude protein (CP) and neutral-detergent fibre (NDF) increased linearly. Rumen pH decreased quadratically, and total volatile fatty acids (VFA) increased quadratically. Acetate molar percentage and acetate:propionate ratio increased linearly, but propionate molar percentage and ammonia-N content decreased linearly. Rumen effective degradability of DM increased linearly, NDF increased quadratically but CP was unaltered. Activity of cellulase and populations of total bacteria, protozoa, fungi, dominant cellulolytic bacteria, Prevotella ruminicola and Ruminobacter amylophilus increased linearly. Linear increase was observed for urinary total purine derivatives excretion. The data suggested that dietary RF addition was essential for rumen microbial growth, and no further increase in performance and rumen total VFA concentration was observed when increasing RF level from 600 to 900 mg/d in dairy bulls.

Coated copper sulphate (CCS) could be used as a Cu supplement in cows. To investigate the influences of copper sulphate (CS) and CCS on milk performance, nutrient digestion and rumen fermentation, fifty Holstein dairy cows were arranged in a randomised block design to five groups: control, CS addition (7·5 mg Cu/kg DM from CS) or CCS addition (5, 7·5 and 10 mg Cu/kg DM from CCS, respectively). When comparing Cu source at equal inclusion rates (7·5 mg/kg DM), cows receiving CCS addition had higher yields of fat-corrected milk, milk fat and protein; digestibility of DM, organic matter (OM) and neutral-detergent fibre (NDF); ruminal total volatile fatty acid (VFA) concentration; activities of carboxymethyl cellulase, cellobiase, pectinase and α-amylase; populations of Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes; and liver Cu content than cows receiving CS addition. Increasing CCS addition, DM intake was unchanged, yields of milk, milk fat and protein; feed efficiency; digestibility of DM, OM, NDF and acid-detergent fibre; ruminal total VFA concentration; acetate:propionate ratio; activity of cellulolytic enzyme; populations of total bacteria, protozoa and dominant cellulolytic bacteria; and concentrations of Cu in serum and liver increased linearly, but ruminal propionate percentage, ammonia-N concentration, α-amylase activity and populations of Prevotella ruminicola and Ruminobacter amylophilus decreased linearly. The results indicated that supplement of CS could be substituted with CCS and addition of CCS improved milk performance and nutrient digestion in dairy cows.

Se can enhance lactation performance by improving nutrient utilization and antioxidant status. However, sodium selenite (SS) can be reduced to non-absorbable elemental Se in the rumen, thereby reducing the intestinal availability of Se. The study investigated the impacts of SS and coated SS (CSS) supplementation on lactation performance, nutrient digestibility, ruminal fermentation and microbiota in dairy cows. Sixty multiparous Holstein dairy cows were blocked by parity, daily milk yield and days in milk and randomly assigned to five treatments: control, SS addition (0.3 mg Se/kg DM as SS addition) or CSS addition (0.1, 0.2 and 0.3 mg Se/kg DM as CSS addition for low CSS (LCSS), medium CSS (MCSS) and high CSS (HCSS), respectively). Experiment period was 110 days with 20 days of adaptation and 90 days of sample collection. Dry matter intake was higher for MCSS and HCSS compared with control. Yields of milk, milk fat and milk protein and feed efficiency were higher for MCSS and HCSS than for control, SS and LCSS. Digestibility of DM and organic matter was highest for CSS addition, followed by SS addition and then control. Digestibility of CP was higher for MCSS and HCSS than for control, SS and LCSS. Higher digestibility of ether extract, NDF and ADF was observed for SS or CSS addition. Ruminal pH decreased with dietary Se addition. Acetate to propionate ratio and ammonia N were lower, and total volatile fatty acids (VFAs) concentration was greater for SS, MCSS and HCSS than control. Ruminal H ion concentration was highest for MCSS and HCSS and lowest for control. Activities of cellobiase, carboxymethyl-cellulase, xylanase and protease and copies of total bacteria, fungi, Ruminococcus flavefaciens, Fibrobacter succinogenes and Ruminococcus amylophilus increased with SS or CSS addition. Activity of α-amylase, copies of protozoa, Ruminococcus albus and Butyrivibrio fibrisolvens and serum glucose, total protein, albumin and glutathione peroxidase were higher for SS, MCSS and HCSS than for control and LCSS. Dietary SS or CSS supplementation elevated blood Se concentration and total antioxidant capacity activity. The data implied that milk yield was elevated due to the increase in total tract nutrient digestibility, total VFA concentration and microorganism population with 0.2 or 0.3 mg Se/kg DM from CSS supplementation in dairy cows. Compared with SS, HCSS addition was more efficient in promoting lactation performance of dairy cows.

The combined addition of branched-chain volatile fatty acids (BCVFAs) and folic acid (FA) could improve growth performance and nutrient utilization by stimulating ruminal microbial growth and enzyme activity. This study was conducted to evaluate the effects of BCVFA and FA addition on growth performance, ruminal fermentation, nutrient digestibility, microbial enzyme activity, microflora and excretion of urinary purine derivatives (PDs) in calves. Thirty-six Chinese Holstein weaned calves (60 ± 5.4 days of age and 107 ± 4.7 kg of BW) were assigned to one of four groups in a randomized block design. Treatments were control (without additives), FA (with 10 mg FA/kg dietary DM), BCVFA (with 5 g BCVFA/kg dietary DM) and the combined addition of FA and BCVFA (10 mg/kg DM of FA and 5 g/kg DM of BCVFA). Supplements were hand-mixed into the top one-third of total mixed ration. Dietary concentrate to maize silage ratio was 50 : 50 on a DM basis. Dietary BCVFA or FA addition did not affect dry matter intake but increased average daily gain (ADG) and feed conversion efficiency. Ruminal pH and ammonia N were lower, and total volatile fatty acids (VFAs) concentration was higher for BCVFA or FA addition than for control. Dietary BCVFA or FA addition did not affect acetate proportion but decreased propionate proportion and increased acetate to propionate ratio. Total tract digestibility of DM, organic matter, CP and NDF was higher for BCVFA or FA addition than for control. Dietary BCVFA or FA addition increased activity of carboxymethyl cellulase and cellobiase, population of total bacteria, fungi, Ruminococcus albus, R. flavefaciens, Fibrobacter succinogenes and Prevotella ruminicola as well as total PD excretion. Ruminal xylanase, pectinase and protease activity and Butyrivibrio fibrisolvens population were increased by BCVFA addition, whereas population of protozoa and methanogens was increased by FA addition. The BCVFA × FA interaction was significant for acetate to propionate ratio, cellobiase activity and total PD excretion, and these variables increased more with FA addition in diet without BCVFA than in diet with BCVFA. The data indicated that supplementation with BCVFA or FA increased ADG, nutrient digestibility, ruminal total VFA concentration and microbial protein synthesis by stimulating ruminal microbial growth and enzyme activity in calves.

Two tree peony species, Paeonia ostii and Paeonia rockii, from eight different provenances in China (four provenances for each species) were collected for their photosynthetic characteristics. Their diurnal variations of photosynthesis, the light- and CO2-response curves and chlorophyll content were determined. Among all eight provenances, Ziwuling P. rockii had a significantly higher average daily net photosynthetic rate, showing a superior photosynthetic capacity, followed by Fengxiang P. ostii and Xunyang P. ostii. In addition, Ziwuling P. rockii had the highest maximum net photosynthetic rates, thus, presented a strong photosynthetic potential. Furthermore, Xunyang P. ostii, Fengxiang P. ostii, and Heze P. ostii also exhibited a great photosynthetic capacity and light adaptability, which was consistent with their high chlorophyll a/b values. Taken together, Ziwuling P. rockii had the strongest photosynthetic capacity among all tested sources, followed by Fengxiang P. ostii, and Xunyang P. ostii, which are recommended to be used as seed sources for oil peony cultivation and cross-breeding.

This study evaluated the effects of branched-chain volatile fatty acids (BCVFA) and rumen protected folic acid (RPFA) supplementation on lactation performance, ruminal fermentation, nutrient digestion and blood metabolites in dairy cows. Fifty-six multiparous Chinese Holstein cows (3.2 ± 1.1 of parity, 631 ± 16.4 kg of body weight [BW], 65 ± 2.6 days in milk [DIM] and 30.2 ± 2.1 kg of milk yield per day, mean ± SD) were blocked by lactation number, milk yield per day and DIM and were arranged into one of four groups in a randomized block design with a 2 × 2 factorial arrangement. Supplemental BCVFA (0 g/d [BCVFA-] or 80 g/d [BCVFA+]) and RPFA (0 mg/d [RPFA-] or 128 mg/d [RPFA+]) were hand-mixed into the top one-third of total mixed ration. Dietary concentrate to forage ratio was 50:50 based on a dry matter (DM) basis. Experimental periods comprised 105 days with 15 d of adaptation followed by 90 d of data collection. DM intake was increased with BCVFA supplementation, but was unaffected by RPFA. The BW changes were similar among treatments. Yields of milk, milk fat and lactose were increased, and milk true protein yield tended to increase with BCVFA or RPFA supplementation. Milk fat percentage was increased with BCVFA supplementation, but was unaffected by RPFA. Percentage of milk true protein was increased, lactose was unaltered and feed conversion ratio was decreased with BCVFA or RPFA supplementation. Ruminal pH and ammonia N concentration were decreased, but total volatile fatty acids concentration was increased with BCVFA or RPFA supplementation. Molar proportion of acetate was increased and propionate was decreased, resulting in an increased ratio of acetate to propionate with BCVFA supplementation. Acetate and propionate molar proportion and the ratio of acetate to propionate were not affected by RPFA. Digestibilities of DM, organic matter, crude protein, non-fiber carbohydrates, neutral detergent fibre and acid detergent fibre were increased with BCVFA or RPFA supplementation. Similarly, activities of caboxymethyl-cellulase, cellobiase, xylanase, pectinase, α-amylase and protease and abundance of R. albus, R. flavefaciens, F. succinogenes, B. fibrisolvens and P. ruminicola were increased. However, R. amylophilus abundance was not affected by BCVFA and increased with RPFA supplementation. Serum concentrations of glucose and non-esterified fatty acids (NEFA) were unaltered and total protein was increased with BCVFA or RPFA supplementation. Serum acetoacetate (ACAC) and BHBA were increased by BCVFA, but were decreased by RPFA. Supplementation of BCVFA or RPFA increased serum growth hormone releasing hormone, growth hormone and insulin-like growth factor-1. These results indicated that lactation performance, ruminal fermentation, nutrient digestion and hormone secretion improved due to the stimulated ruminal bacteria growth and enzyme activity with BCVFA or RPFA supplementation, but no BCVFA × RPFA interaction was detected during the trial.

This study evaluated the effects of branched-chain volatile fatty acids (BCVFA) supplementation on growth performance, ruminal fermentation, nutrient digestibility, hepatic lipid content and gene expression of dairy calves. Forty-eight Chinese Holstein male calves (10 months of age; 345 ± 6.4 kg of body weight [BW]) were assigned randomly to four treatments with 0, 60, 120 and 180 mg BCVFA per kg BW per day for each calf. Supplemental BCVFA was hand-mixed into the top third of the daily ration and fed to calves for 100 days to the experimental treatments. Supplementation of BCVFA in calves ration increased ADG and feed conversion linearly. Dry matter (DM) intake was unaffected, but digestibilitiy of DM, organic matter, crude protein, ether extract, neutral detergent fibre and acid detergent fibre increased linearly with increasing levels of BCFVA supplementation. Similarly, Supplementation of BCVFA linearly decreased ruminal pH and ammonia-N but increased total VFAs. Molar proportion of acetate linearly increased, whereas propionate linearly decreased and the ratio of acetate to propionate increased linearly with increasing BCVFA in rations. Relative mRNA expressions of peroxisome-proliferator-activated receptor α and carnitine palmitoyl transferase-1 linearly increased with BCVFA levels. The results suggested that BCVFA supplementation improved ruminal fermentation, nutrient digestibility and growth of calves with promoted hepatic lipid oxidation. Due to the unsignificant difference between 120 and 180 mg groups for all parameters, the optimum supplementary dose of BCVFA was 120 mg per kg BW per day.

Isovalerate supplements could stimulate rumen development by improving morphology and function of rumen mucosa, and then promote the growth of calves. This study was done to evaluate the effects of isovalerate supplements on morphology and functional gene expression of rumen mucosa in dairy calves. In total, 48 Chinese Holstein male calves with 15 days of age and 45.1±0.36 kg of BW were randomly assigned to four groups. The treatments were: control, low-isovalerate, moderate-isovalerate and high-isovalerate with 0, 3, 6 and 9 g isovalerate per calf per day, respectively. Supplementary isovalerate was hand-mixed into milk in pre-weaning calves and into concentrate portion in post-weaning calves. The study consisted of a 15-day-adaptation period and a 60-day-sampling period. Calves were weaned at 60 days of age. Three calves were slaughtered from each of the four treatments at 30, 60 and 90 days of age. The weight of body and stomach were measured, samples of ruminal tissues and blood were analyzed. Total stomach weight, total stomach to BW ratio, rumen wall and keratinized layer thickness, serum growth hormone and IGF-1 for both pre- and post-weaning calves increased linearly with increasing isovalerate supplements. Rumen to total stomach weight ratio, the length and width of rumen papillae, and serum β-hydroxybutyrate increased linearly for post-weaning calves. However, abomasum weight to total stomach weight ratio decreased linearly for both pre- and post-weaning calves. The relative messenger RNA expression for growth hormone receptor, IGF-1 receptor and 3-hydroxy-3-methylglutaryl-CoA synthase 1 in rumen mucosa increased linearly for post-weaning calves. Our results suggested that isovalerate supplements promoted rumen development in a dose-dependent manner. The optimum dose was 6.0 g isovalerate per calf per day.

The first Water Cherenkov detector of the LHAASO experiment (WCDA-1) has been operating since April 2019. The data for the first year have been analyzed to test its performance by observing the Crab Nebula as a standard candle. The WCDA-1 achieves a sensitivity of 65 mCU per year, with a statistical threshold of 5 . To accomplish this, a 97.7% cosmic-ray background rejection rate around 1 TeV and 99.8% around 6 TeV with an approximate photon acceptance of 50% is achieved after applying an algorithm to separate gamma-induced showers. The angular resolution is measured using the Crab Nebula as a point source to be approximately 0.45° at 1 TeV and better than 0.2° above 6 TeV, with a pointing accuracy better than 0.05°. These values all match the design specifications. The energy resolution is found to be 33% for gamma rays around 6 TeV. The spectral energy distribution of the Crab Nebula in the range from 500 GeV to 15.8 TeV is measured and found to be in agreement with the results from other TeV gamma ray observatories.

This study evaluated the influences of guanidinoacetic acid (GAA) and betaine (BT) on growth performance, nutrient digestion and ruminal fermentation in bulls. Forty-four Angus bulls were blocked by live body weight and then randomly divided into four groups in a 2 × 2 factorial design. Betaine of 0 or 0.6 g/kg dry matter (DM) was added to diets containing 0 or 0.6 g/kg DM GAA, respectively. The experiment included a 20 day period for adaptation and a 60 day period for data collection. Average daily gain and feed efficiency were increased by GAA or BT but no further increase was observed for supplementing BT and GAA together than for addition with BT or GAA alone. Supplementary GAA or BT did not influence DM intake but increased apparent digestibility of DM, organic matter (OM), crude protein (CP) and acid detergent fibre (ADF). Digestibility of neutral detergent fibre (NDF) was increased by GAA inclusion but was unaltered with BT provision. Ruminal pH reduced but total volatile fatty acids and ammonia nitrogen elevated with dietary inclusion of GAA or BT. Rumen short chain fatty acids percentages and fermentation pattern were not influenced by GAA. Dietary inclusion of BT increased molar proportions of acetate, valerate, isobutyrate and isovalerate as well as the ratio of acetate to propionate. Rumen populations of Ruminococcus flavefaciens and Fibrobacter succinogenes increased with addition of GAA or BT and the increase was greater when BT was added in diets with GAA compared to diets without GAA. Addition of GAA or BT increased activities of cellobiase, xylanase, α-amylase and protease and populations of total bacteria, cellulolytic bacteria and Ruminobacter amylophilus but did not affect Prevotella ruminicola. Addition of BT increased carboxymethyl-cellulase and pectinase activities and total fungi population. Blood creatine content was increased by GAA or BT and was greater for addition of GAA and BT together than for GAA or BT addition alone. Serum contents of glucose, folate, arginine and methionine were unchanged but total protein increased with GAA or BT provision. Blood homocysteine content was unaffected by GAA but decreased with BT supplementation. The data showed that GAA or BT addition improved growth performance and feed efficiency but supplementing GAA and BT together did not further increase the performance of bulls when compared with GAA or BT inclusion alone.

Isobutyrate supplements could improve rumen development by increasing ruminal fermentation products, especially butyrate, and then promote the growth performance of calves. The objective of this study was to evaluate the effects of isobutyrate supplementation on growth performance, rumen development, blood metabolites and hormone secretion in pre- and post-weaned dairy calves. In total, 56 Chinese Holstein male calves with 30 days of age and 72.9±1.43 kg of BW, blocked by days of age and BW, were assigned to four groups in a randomized block design. The treatments were as follows: control, low-isobutyrate, moderate-isobutyrate and high-isobutyrate with 0, 0.03, 0.06 and 0.09 g isobutyrate/kg BW per calf per day, respectively. Supplemental isobutyrate was hand-mixed into milk of pre-weaned calves and the concentrate portion of post-weaned calves. The study consisted of 10 days of an adaptation period and a 50-day sampling period. Calves were weaned at 60 days of age. Seven calves were chosen from each treatment at random and slaughtered at 45 and 90 days of age. BW, dry matter (DM) intake and stomach weight were measured, samples of ruminal tissues and blood were determined. For pre- and post-weaned calves, DM intake and average daily gain increased linearly (P

This experiment was done to investigate the influences of supplementary rumen-protected folic acid (RPFA) on ruminal fermentation parameters, microbial enzyme activity, cellulolytic bacteria and urinary excretion of purine derivatives in growing beef steers. Eight ruminally fistulated Jinnan beef steers (398.4 ± 1.9 kg) were used in a repeated 4 × 4 Latin square experimental design. The treatments were: control (without RPFA), low RPFA (LRPFA), medium RPFA (MRPFA) and high RPFA (HRPFA) with 0, 0.6, 1.2 and 1.8 g RPFA per steer per day, respectively. The dietary corn silage to concentrate ratio was 50:50 (dry matter [DM] basis). The dry matter intake was confined to 95% of voluntary intake. Mean ruminal pH was quadratically reduced with altering RPFA supplementation, and was the lowest for MRPFA and HRPFA, highest for the control, and intermediate for the LRPFA. Ruminal total VFA concentration was quadratically increased with increasing RPFA supplementation and was higher in MRPFA than in control. The ratio of acetate to propionate was quadratically increased due to the increased acetate concentration and the unchanged propionate concentration. Ruminal degradabilities of DM and neutral detergent fibre of corn silage, and DM and crude protein of concentrate mix increased quadratically with increasing RPFA supplementation. Ruminal enzyme activity of cellobiase, xylanase, pectinase and α-amylase quadratically increased and was higher in MRPFA than in control. The populations of B. fibrisolvens, R. albus, R. flavefaciens and F. succinogenes quadratically increased with altering the supplementary PRFA. Urinary excretion of purine derivatives quadratically increased with altering RPFA supplementation and was higher in HRPFA and MRPFA than in LRPFA and control. The results indicated that dietary supplements of RPFA improved ruminal fermentation, in situ ruminal degradation and urinary excretion of purine derivatives. It was suggested that the RPFA regulated the activity of rumen microbe or enzymes in a concentration-dependent manner. Under this experimental condition, the appropriate dose of RPFA was at 1.2 g/d for steer.

The objective of this study was to evaluate the effects of 2-methylbutyrate supplementation on growth performance and rumen development in pre- and post-weaned dairy calves. Fifty-six Chinese Holstein male calves with 15 days of age and 46.5 ± 0.37 kg of body weight (BW) were randomly assigned to one of four groups. The treatments were: control, low-2-methylbutyrate (LMB), moderate-2-methylbutyrate (MMB) and high-2-methylbutyrate (HMB) with 0, 3, 6 and 9 g 2-methylbutyrate per calf per day, respectively. Supplemental 2-methylbutyrate was hand- mixed into milk in pre-weaned calves and the concentrate portion of post-weaned calves. The study lasted 75 days, including a 15-day adaptation period and followed by a 60-day sampling period. Calves were weaned at 60 days of age. Six calves were chosen from each treatment at random and slaughtered at 30 and 90 days of age. Body weight, dry matter (DM) intake and stomach weight were measured, samples of ruminal tissues and blood were determined. DM intake increased linearly (P

3Ag2 and AuAg). The results show that the migration mechanisms of He atoms mainly depend on the crystal structures of alloys, and their migration energy barriers are aected by the migration paths in Au‐Ag alloys. He interstitials preferentially occupied the most stable sites, but it is dicult for He interstitials to migrate to nearest most stable sites via second stable positions at room temperature. When He atom is at the tetrahedral position which has higher formation energy, it possibly migrates to nearest tetrahedral positions directly for AuAg alloy. In addition, comparing the migration of He defects in the two alloys, we found that the properties of migration energy and relative stability of He atoms probably slightly depend on the mass‐density of Au‐Ag alloys.

The objective of this study was to evaluate the effects of dietary supplements of rumen-protected folic acid (RPFA) on lactation performance, energy balance, reproductive performance and blood parameters of dairy cows. Ninety-six multiparous Holstein cows were assigned to four groups of 24 each according to their previous 305-days milk production. The treatments were: control, low RPFA (LRPFA), medium RPFA (MRPFA) and high RPFA (HRPFA) with 0–3 g RPFA/cow per day, respectively. Supplements of RPFA were top-dressed and manually mixed into the upper one third of the ration during the morning feeding from 3 weeks before the expected calving date to 15 weeks after parturition. Dry matter (DM) and net energy (NE) intakes, milk yield, milk protein content and production increased linearly ( P P P P P

A highly porous titanium foam with open cells was made by the process of impregnating polymer foam in slurry and then sintering, which displayed a three-dimensional reticular structure with interconnected pores. For this reticular titanium foam, the electromagnetic shielding performance was investigated in the frequency range of 0.3–3000 MHz (covering that of radio waves). The experimental results indicated the porous samples displayed an evident effectiveness of electromagnetic shielding, especially a good performance at low frequencies. The shielding effectiveness presented an overall tendency of decrease with the increase of the frequency, and the corresponding curve shows a fluctuating region when the frequency is higher than some value. In this region, the shielding effectiveness fluctuated around an average value. In the whole range of testing frequency, the shielding effectiveness could be remarkably enhanced when the thickness increased for the sample with the same pore-parameter. In addition, this titanium foam exhibited a relatively low thermal conductivity, which was measured to be about 0.4–0.8 W/(m·K) at room temperature for the sample with the porosity of 87%–89%. Besides, the thermal conductivity showed a greatly decreasing tendency when increasing the porosity of the sample. Keywords: Porous metal, Metal foam, Titanium foam, Electromagnetic shielding, Thermal conductivity

This study investigated the effects of palm fat powder (PFP) and coated folic acid (CFA) supplementation on performance, energy balance, nutrient digestion, ruminal fermentation and blood metabolites in early lactation dairy cows. Thirty-two multiparous Holstein dairy cows were arranged into four treatments in a 2 × 2 factorial randomized block design. Supplemental PFP (0 g/d [PFP−] or 500 g/d [PFP+]) and CFA (0 mg/d [CFA−] or 135 mg/d of folic acid from CFA [CFA+]) were mixed into the top one-third of the daily ration from d 52 prepartum (based on expected calving date) to d 42 postpartum. Dry matter intake was unaltered but milk yield, milk fat content and feed efficiency increased with PFP or CFA supplementation. Milk protein content was not affected by PFP but increased with CFA supplementation. Body weight change was not affected by PFP or CFA supplementation. Energy balance increased with PFP supplementation but decreased with CFA supplementation. Apparent total-tract digestibility of dry matter, organic matter, crude protein, non-fiber carbohydrates, aNDF, ADF and gross energy, ruminal pH and total volatile fatty acids concentration were unchanged with PFP supplementation but increased with CFA supplementation. Ruminal acetate to propionate ratio was decreased by PFP but increased with CFA supplementation. Lower ammonia-N was observed for PFP or CFA supplementation. Activity of α-amylase and population of Butyrivibrio (B.) fibrisolvens and Ruminobacter (Rb.) amylophilu increased but total protozoa decreased with PFP supplementation. Supplementation of CFA increased activity of cellobiase, xylanase, pectinase, α-amylase and protease and population of total bacteria, fungi, protozoa, Ruminococcus (R.) albus, R. flavefaciens, Fibrobacter succinogenes, B. fibrisolvens, Prevotella ruminicola and Rb. amylophilus. Significant PFP × CFA interaction was not observed during the trial. The results indicated that dietary supplementation of PFP or/and CFA had the potential to improve performance of early lactation dairy cows.

The objective of this study was to evaluate the effects of 2-methylbutyrate supplementation on rumen microflora, enzyme activities and methane production in Simmental steers consuming a diet consisting of 600 g/kg corn stover and 400 g/kg concentrate (dry matter [DM] basis). Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square design. The treatments were: control (without 2-methylbutyrate), low 2-methylbutyrate (LMB), medium 2-methylbutyrate (MMB) and high 2-methylbutyrate (HMB) with 0, 8.4, 16.8 and 25.2 g 2-methylbutyrate per steer and per day, respectively. Dry matter intake (averaged 9 kg/day) was restricted to a maximum of 0.9 of ad libitum intake. Whether direct counts, roll-tube technique or real-time PCR quantification were used, populations of total bacteria, cellulolytic bacteria and anaerobic fungi linearly increased (P

The High Energy cosmic-Radiation Detection (HERD) facility is one of several space astronomy payloads onboard China's Space Station, which is planned for operation starting around 2025 for about 10 ...

Microstructure modification and pressurized solidification were conducted to improve the mechanical property of AZ91 alloy. The addition of SiC inoculants causes remarkable grain refinement and formation of Mg 2 Si phase with script-like morphology. After solution treatment, the spheroidization process of Mg 2 Si phase is elucidated and its morphology transforms into particulate-shaped with smooth boundary. Moreover, pressurized solidification is beneficial for enhancing the feeding behavior of residual liquid and the relative density increases continuously with increasing the applied pressure. Due to the combined effect of grain size strengthening, solution strengthening and reduction of stress concentration of brittle phase, maximum tensile strength reaches 167 MPa as for refined AZ91 alloy coupled with exerting pressure during solidification and solution treatment.

In this work, a comprehensive model is established to predict the surface roughness achieved by single point diamond turning. In addition to the calculation of the roughness components in relation to the kinematics and minimum undeformed chip thickness, the newly developed model also takes the effects of plastic side flow and elastic recovery of materials as machined into account. Moreover, the ‘size effect’ has also been successfully integrated into the model, i.e. an inflection point appears in the trend line of predicted surface roughness as the ratio of maximal undeformed chip thickness to cutting edge radius (hDmax/rn) is equal to one unit. Face turning experiments validate that the maximal prediction error is only 13.35%. As the ratio of hDmax/rn is higher than one unit, both the prediction and experiments reveal that a conservation law exists in diamond turned surface roughness, owing to the competitive effects of kinematics, minimum undeformed chip thickness, plastic side flow and elastic recovery of materials on surface formation. Under the conservation law, the freedom control for an invariable surface roughness can be fulfilled in response to a quantitative ratio of hDmax/rn, either through an accurate configuration of feed rate and depth of cut with fixed tool nose radius and cutting edge radius, or by a reasonable selection of tool nose radius and controlled cutting edge radius with designed feed rate and depth of cut.

Pressurized solidification in combination with grain refinement by rare element was performed for conventional AZ91D magnesium alloy. Both the resultant microstructure and mechanical properties of as-cast ingots were studied. After the addition of 0.75 wt% Ce into AZ91D alloy, a comparable grain refinement can be achieved and an acicular phase Al 11 Ce 3 is formed near the grain boundary. Affected by applying certain amount of pressure during solidification process, micro-segregation is weakened and the amount of shrinkage void in the microstructure is reduced due to the enhancement of flow and feeding capacity of residual liquid. Mechanical property evaluation reveals that the adoption of pressure with 0.2 MPa during solidification generates significant improvement of tensile strength, which gives a promising method for the production of high performance lightweight magnesium alloy.