THE Z-PHASE IN 9Cr FERRITIC/MARTENSITIC HEAT RESISTANT STEEL

Yin, F.S.,Chen, F.X.,Jiang, X.B.,Xue, B.,Zhou, L.,Jung, W.S. World Scientific Publishing 2009 International Journal of Modern Physics B Vol.23 No.6

Effects of Dietary Coptis Chinensis Herb Extract on Growth Performance, Nutrient Digestibility, Blood Characteristics and Meat Quality in Growing-finishing Pigs

Zhou, T.X.,Zhang, Z.F.,Kim, I.H. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.1

The effects of dietary Coptis chinensis herb extract (CHE) on growth performance, blood characteristics, nutrient digestibility and meat quality of growing-finishing pigs were investigated in an 18-wk feeding trial. A total of 36 Landrace${\times}$Yorkshire-Duroc pigs with an initial body weight of $20{\pm}1.0$ kg were randomly assigned to 3 dietary treatments with 6 replications per treatment and 2 pigs per pen. A maize-soybean meal-based diet was formulated as a control diet and other treatment diets were supplemented with 0.5, or 1 g CHE/kg, respectively. After the feeding period, meat samples were collected from those pigs that had reached the market BW. During the experimental periods, growth performance and apparent total tract digestibility of dry matter and nitrogen were unaffected (p>0.05) by the dietary supplementation of CHE. Plasma erythrocytes counts were increased (Linearly, p<0.05) in response to application of CHE at the end of the experiment. Moreover, pigs fed the CHE diets had better (p<0.05) meat color, pH and water holding capacity (WHC) than pigs fed the control diet. In conclusion, dietary supplementation with CHE could increase blood erythrocytes counts and improve meat quality in growing-finishing pigs but not improve growth performance.

Application of fractals to study the corroded reinforced concrete beam

Fan, Y.F.,Zhou, J.,Hu, Z.Q. Techno-Press 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.20 No.3

This paper is focused on fractal analysis of the surface cracking, a new tool for safety evaluation of corroded reinforced concrete (RC) beams. Comprehensive experimental investigations, including flexural tests, coupon tests on strength evaluation of corroded concrete and rusty rebar, and pullout tests to determine bond strength between concrete and rebar were carried out on nine Corroded Reinforced Concrete Beams (CRCB) exposed to an aggressive environment for more than 10 years. In combination with test results from a previous study on CRCBs fabricated in the laboratory from accelerated methods, it is found that, for both types of beams, the surface cracking distributions are fractal in character at loading and failure stages. Fractal dimension is calculated for all specimens at different corrosion states based on fractal analysis method. Relationships between the fractal dimension and mechanical properties of corroded concrete, rebar corrosion ratio, and ductility of CRCBs are discussed in detail. It is concluded that the fractal dimension can act as a damage index and can be efficiently used to describe the corrosion state of CRCBs.

Modeling of wind and temperature effects on modal frequencies and analysis of relative strength of effect

Zhou, H.F.,Ni, Y.Q.,Ko, J.M.,Wong, K.Y. Techno-Press 2008 Wind and Structures, An International Journal (WAS Vol.11 No.1

Wind and temperature have been shown to be the critical sources causing changes in the modal properties of large-scale bridges. While the individual effects of wind and temperature on modal variability have been widely studied, the investigation about the effects of multiple environmental factors on structural modal properties was scarcely reported. This paper addresses the modeling of the simultaneous effects of wind and temperature on the modal frequencies of an instrumented cable-stayed bridge. Making use of the long-term monitoring data from anemometers, temperature sensors and accelerometers, a neural network model is formulated to correlate the modal frequency of each vibration mode with wind speed and temperature simultaneously. Research efforts have been made on enhancing the prediction capability of the neural network model through optimal selection of the number of hidden nodes and an analysis of relative strength of effect (RSE) for input reconstruction. The generalization performance of the formulated model is verified with a set of new testing data that have not been used in formulating the model. It is shown that using the significant components of wind speeds and temperatures rather than the whole measurement components as input to neural network can enhance the prediction capability. For the fundamental mode of the bridge investigated, wind and temperature together apply an overall negative action on the modal frequency, and the change in wind condition contributes less to the modal variability than the change in temperature.

Exact calculation of natural frequencies of repetitive structures

Williams, F.W.,Kennedy, D.,Wu, Gaofeng,Zhou, Jianqing Techno-Press 1996 Structural Engineering and Mechanics, An Int'l Jou Vol.4 No.5

Finite element stiffness matrix methods are presented for finding natural frequencies (or buckling loads) and modes of repetitive structures. The usual approximate finite element formulations are included, but more relevantly they also permit the use of 'exact finite elements', which account for distributed mass exactly by solving appropriate differential equations. A transcendental eigenvalue problem results, for which all the natural frequencies are found with certainty. The calculations are performed for a single repeating portion of a rotationally or linearly (in one, two or three directions) repetitive structure. The emphasis is on rotational periodicity, for which principal advantages include: any repeating portions can be connected together, not just adjacent ones; nodes can lie on, and members along, the axis of rotational periodicity; complex arithmetic is used for brevity of presentation and speed of computation; two types of rotationally periodic substructures can be used in a multi-level manner; multi-level non-periodic substructuring is permitted within the repeating portions of parent rotationally periodic structures or substructures and; all the substructuring is exact, i.e., the same answers are obtained whether or not substructuring is used. Numerical results are given for a rotationally periodic structure by using exact finite elements and two levels of rotationally periodic substructures. The solution time is about 500 times faster than if none of the rotational periodicity had been used. The solution time would have been about ten times faster still if the software used had included all the substructuring features presented.

Effects of Alfalfa Meal on Growth Performance and Gastrointestinal Tract Development of Growing Ducks

Jiang, J.F.,Song, X.M.,Huang, X.,Zhou, W.D.,Wu, J.L.,Zhu, Z.G.,Zheng, H.C.,Jiang, Y.Q. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.10

A study was conducted to evaluate effects of alfalfa meal on growth performance and gastrointestinal tract development of growing layer ducks to provide evidence for application of alfalfa meal in the duck industry. Two hundred and fifty-six healthy Shaoxing 7-wk old growing layer ducks were selected and randomly allocated to 1 of 4 dietary treatments based on corn and soybean meal and containing 0, 3, 6, and 9% of alfalfa meal for 8 wks. Each treatment consisted of 4 replicates of 16 ducks each. Briefly, birds were raised in separate compartments, and each compartment consisted of three parts: indoor floor house, adjacent open area and a connecting water area. The results showed: i) Growing ducks fed alfalfa meal diet were not significantly different in average daily gain, feed intake and gain-to-feed ratio from those fed no alfalfa diet (p>0.05). ii) Alfalfa meal increased the ratio crop, gizzard to live weight, caecum to live weight, the caecum index of growing ducks (p<0.05). iii) Villus height in duodenum and jejunum of growing ducks increased significantly with the increase of alfalfa meal levels (p<0.05). Crypt depth in duodenum and jejunum of growing ducks decreased significantly with the increase of alfalfa meal levels (p<0.05). This experiment showed that feeding of alfalfa meal to growing layer ducks could improve gastrointestinal tract growth and small intestinal morphology without effect on performance. This experiment provides evidence that alfalfa meal is a very valuable feedstuff for growing layer ducks.

Effects of Biocom as a Replacement of Glutamine on Performance and Blood Biochemical Indexes of Early Weaned Piglets

Zhou, R.Y.,Peng, J.,Liu, Z.L.,Fang, Z.F. Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.6

The objective of this study was to evaluate Biocom (a protein source containing a high level of glutamine and alanyl-glutamine) as a replacement for glutamine (Gln) in nursery pig diets. Forty-two pigs (fourteen pigs per treatment) weaned at 28 d of age were used in a 28-d performance trial using three dietary treatments: control (no Gln), control supplemented with Gln or Biocom. The control diet was composed of corn, soybean meal, whey and fish meal. Individual body weight, pen feed disappearance and diarrhea were monitored. On d 0, 2, 7 and 14 postweaning, respectively, five pigs per treatment were selected and bled from the anterior vena cava to obtain five replicate samples of blood on each dietary treatment for determination of blood biochemical index. Dietary supplementation of Gln and Biocom did not influence performance, plasma Gln and total serum protein concentration (p>0.05). However, the addition of Gln and Biocom could prevent serum urea nitrogen and serum cortisol from increasing on d 2 postweaning (p<0.05). There were no significant differences (p>0.05) in any of the examined parameters between Gln- and Biocom-supplemented diets. In conclusion, dietary Gln did not influence the performance of early-weaned piglets owing to the complex diet containing whey, but could prevent the increase of serum urea and cortisol. Biocom could be used as a replacement for free pure Gln without any negative effect on early-weaned piglets.

Effects of Rice Straw Particle Size on Chewing Activity, Feed Intake, Rumen Fermentation and Digestion in Goats

Zhao, X.G.,Wang, M.,Tan, Z.L.,Tang, S.X.,Sun, Z.H.,Zhou, C.S.,Han, X.F. Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.9

Effects of particle size and physical effective fibre (peNDF) of rice straw in diets on chewing activities, feed intake, flow, site and extent of digestion and rumen fermentation in goats were investigated. A 4${\times}$4 Latin square design was employed using 4 mature Liuyang black goats fitted with permanent ruminal, duodenal, and terminal ileal fistulae. During each of the 4 periods, goats were offered 1 of 4 diets that were similar in nutritional content but varied in particle sizes and peNDF through alteration of the theoretical cut length of rice straw (10, 20, 40, and 80 mm, respectively). Dietary peNDF contents were determined using a sieve for particle separation above 8 mm, and were 17.4, 20.9, 22.5 and 25.4%, respectively. Results showed that increasing the particle size and peNDF significantly (p<0.05) increased the time spent on rumination and chewing activities, duodenal starch digestibility and ruminal pH, and decreased ruminal starch digestibility and $NH_{3}$-N concentration. Intake and total tract digestibility of nutrients (i.e. dry matter, organic matter, and starch) and ruminal fermentation were not affected by the dietary particle size and peNDF. Increased particle size and peNDF did not affect ruminal fibre digestibility, but had a great impact on the intestinal and total tract fibre digestibility. The study suggested that rice straw particle size or dietary peNDF was the important influential factor for chewing activity, intestinal fibre and starch digestibility, and ruminal pH, but had minimal impact on feed intake, duodenal and ileal flow, ruminal and total tract digestibility, and ruminal fermentation.

Effect of Feeding Enzymolytic Soybean Meal on Performance, Digestion and Immunity of Weaned Pigs

Zhou, S.F.,Sun, Z.W.,Ma, L.Z.,Yu, J.Y.,Ma, C.S.,Ru, Y.J. Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.1

The objective of this study was to investigate the effect of enzymolytic products of soybean meal (ESBM), as one of the protein sources in the diet, on the growth performance, nutrient digestibility and immune function of weaned piglets. Soybean meal produced by bioprocessing with fermentation and enzymolysis contains reduced anti-nutritional factors and improved protein utilization. A total of 240 weaned piglets (Duroc${\times}$Landrace${\times}$Yorkshire, $9.01{\pm}0.22\;kg$ body weight) were randomly allocated to 4 treatments with 6 pens per treatment and 10 piglets per pen. The diets were based on corn-soybean meal and ESBM partially replaced soybean meal and soybean protein isolate at the inclusion level of 5, 10 or 15% in the basal diet. Feed intake and body weight were measured weekly. On days 24 to 27, faeces of each replicate were proportionally collected to determine the nutrient digestibility. On day 28 of the experiment, one piglet from each replicate was slaughtered humanely to collect immune organs. The results showed that inclusion of ESBM increased (p<0.05) the final weight, daily feed intake and daily gain of weaned pigs compared with the control diet, and ESBM at the inclusion levels of 10 and 15% improved (p<0.05) the feed/gain compared with the control diet. There were no differences (p>0.05) in daily feed intake among the levels of ESBM, but increasing the levels of ESBM from 5 to 15% improved (p<0.05) the final weight, average daily gain of pigs and feed/gain. The inclusion of ESBM at 5 to 15% increased (p<0.05) the digestibility of crude protein (CP) by 5 to 16%, and ESBM at 15% increased (p<0.05) the digestibility of digestible energy (DE), Ca and P compared with the control diet. ESBM increased (p<0.05) the relative weights of thymus and mandibular lymph nodes by 57.7 and 29.6%, respectively. The percentages of T lymphocytes, CD4+ and CD8+ in peripheral blood of weaned piglets were also increased (p<0.05) by feeding ESBM. The results suggest that ESBM can be a better protein source in improving growth performance, nutrient digestibility and immune function of weaned piglets.

A pre-stack migration method for damage identification in composite structures

Zhou, L.,Yuan, F.G.,Meng, W.J. Techno-Press 2007 Smart Structures and Systems, An International Jou Vol.3 No.4

In this paper a damage imaging technique using pre-stack migration is developed using Lamb (guided) wave propagation in composite structures for imaging multi damages by both numerical simulations and experimental studies. In particular, the paper focuses on the experimental study using a finite number of sensors for future practical applications. A composite laminate with a surface-mounted linear piezoelectric ceramic (PZT) disk array is illustrated as an example. Two types of damages, one straight-crack damage and two simulated circular-shaped delamination damage, have been studied. First, Mindlin plate theory is used to model Lamb waves propagating in laminates. The group velocities of flexural waves in the composite laminate are also derived from dispersion relations and validated by experiments. Then the pre-stack migration technique is performed by using a two-dimensional explicit finite difference algorithm to back-propagate the scattered energy to the damages and damages are imaged together with the excitation-time imaging conditions. Stacking these images together deduces the resulting image of damages. Both simulations and experimental results show that the pre-stack migration method is a promising method for damage identification in composite structures.