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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2007.03.036 Byline: K.L. Lin (a), W.C. Chang (b), D.F. Lin (c), H.L. Luo (c), M.C. Tsai (c) Keywords: Nano-SiO.sub.2; Sewage sludge ash; Mortar Abstract: The effects of nano-SiO.sub.2 on three ash particle sizes in mortar were studied by replacing a portion of the cement with incinerated sewage sludge ash. Results indicate that the amount of water needed at standard consistency increased as more nano-SiO.sub.2 was added. Moreover, a reduction in setting time became noticeable for smaller ash particle sizes. The compressive strength of the ash-cement mortar increased as more nano-SiO.sub.2 was added. Additionally, with 2% nano-SiO.sub.2 added and a cure length of 7 days, the compressive strength of the ash-cement mortar with 1[mu]m ash particle size was about 1.5 times better that of 75[mu]m particle size. Further, nano-SiO.sub.2 functioned to fill pores for ash-cement mortar with different ash particle sizes. However, the effects of this pore-filling varied with ash particle size. Higher amounts of nano-SiO.sub.2 better influenced the ash-cement mortar with larger ash particle sizes. Author Affiliation: (a) Department of Environmental Engineering, National Ilan University, 1, Section 1, Shen Lung Road, I-Lan 26041, Taiwan, ROC (b) Department of Civil Engineering, Kao Yuan University, No.1821,Chung Shan Road, Lu Chu Hsiang, Kaohsiung County 821, Taiwan, ROC (c) Department of Civil and Ecological Engineering, I-Shou University, 1, Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang , Kaohsiung County 84008, Taiwan, ROC Article History: Received 10 April 2006; Revised 8 March 2007; Accepted 25 March 2007

A novel solar-powered adsorption cooling system for low-temperature grain storage has been built, which consists of a solar-powered water heating system, a silica gel-water adsorption chiller, a cooling tower and a fan coil unit. The adsorption chiller is composed of two identical adsorption units, each of them containing an adsorber, a condenser, and an evaporator/receiver. The two water evaporators have been incorporated into one methanol evaporator by the use of the concept of a gravity heat pipe. In order to improve the system efficiency and achieve continuous cooling production, the adsorbers are operated out-of-phase, and heat and mass recovery processes have been used. During the period from July to September of 2004, the system was put into experimental operation to cool the headspace (i.e., the air volume above the grain) of a grain bin. Three months of operation showed promising performance. The chiller had a cooling power between 66 and 90 W per [m.sup.2] of collector surface, with a daily solar cooling coefficient of performance ([COP.sub.solar]) ranging from 0.096 to 0.13. The electric cooling COP was between 2.6 and 3.4. Keywords: Solar-powered water heating system; Adsorption refrigeration; Water chiller; Low-temperature storage; Grain storage

There is a lack of fossil record of Cambrian chordates, however two distinct types of agnathan from the Lower Cambrian Chengjiang fossil-Langerstatte of the Quiongzhusi Formation at Haikou, Kumming City, Yunnan, have been described. One form is lamprey-like, and the other is closer to the more primitive hagfish.

The present study was undertaken to evaluate the influence of rumen-protected folic acid (RPFA) on slaughter performance, visceral organ and gastrointestinal tract coefficients, and meat quality in lambs. Sixty-six lambs from 120 Hu ewes were selected based on body weight and maternal diets and then assigned to six groups using a randomised block experimental design in a 3 × 2 factorial arrangement. The first factor was folic acid (FA) as RPFA in the maternal diet (0 mg/kg (M0F), 16 mg/kg (M16F) or 32 mg/kg (M32F) on DM basis). The second factor was FA in the lambs' diet from weaning until slaughter (0 mg/kg (OC) or 4·0 mg/kg (OF)). The results indicated that the addition of 16 mg/kg FA to the maternal diet increased pre-slaughter weight (PSW), dressing and meat percentage, the reticulum and omasum coefficients, length of the jejunum and ileum, tail fat and perirenal fat coefficient and a* value of the meat colour. The addition of RPFA to the lambs' diet increased PSW, dressing and meat percentage, eye muscle area, abomasum weight, weight and length of the small intestine, but reduced the coefficients of tail fat. An M × O interaction was observed for the weights of heart, lungs, rumen and total stomach, weight and coefficient of omental fat and the girth rib value. Collectively, RPFA in the maternal and lambs' diet improved slaughter performance and meat quality by stimulating the morphological development of the gastrointestinal tract and the distribution of fat in the body. [ABSTRACT FROM AUTHOR]

Examination of the properties of the Mn and Co-volume-doped acicular gamma-Fe2O3 particles with high coercivity and low content, prepared by a new technique involving high-temperature ion diffusion and step annealing, reveals that these particles exhibit a low-temperature coefficient of coercivity and a high magnetic thermal stability. High uniaxial anisotropy induced by the large anisotropic arrangements of cobalt ions is responsible for the novel characteristics of these particles. Manganese promotes this anisotropic rearrangement during the process of step annealing.

X-ray diffraction studies help study the magnetic and magnetostrictive properties of Ga substituted TbFe2 compounds. The decrease in Curie temperature with increasing Ga substitution is due to the decrease in R-T coupling strength. The enhancement of Ga concentration also reduces magnetostriction and the intersublattice coupling constant. There is a decrease in magnetic properties of TbFe2 compounds when there is an increase in Ga concentration.

X-ray photoelectron spectroscopy of Ho(Fe(1-x)Mnx)2 compounds indicates the absence of chemical shift and a constant binding energy value. Mossbauer studies show a decrease in the average hyperfine fields with an increase in Mn content and a change in isomer shift. This isomeric shift is due to size effects and is not affected by electron transport.

Transverse magnetic field annealing, torque and Mossbauer experiments help study the coercivity promotion and the instability of acicular cobalt ferrite particles containing Fe2+ ions when subjected to magnetic field and temperature. Uniaxial magnetic anisotropy contributes to coercivity promotion and the instability of Co modified iron oxide particles. An Fe2+-Co2+ pair model explains the uniaxial magnetic anisotropy.

X-ray line measurements of size effects and the magnetic properties of fine ferrimagnetic particles show that specific saturation magnetization linearly depends on the specific surface area of the ferrimagnetic crystallites. The spin canting anomaly of the gamma-Co(x)Fe(2-x)O(3) particles differs from that of gamma-Fe2O3 particles. The difference in the slopes representing the anomalies arises due to the distinct anisotropies of the two crystallites.

Experimental analysis of the influence of magnetoannealing on the magnetic properties of Fe-Ag granular films reveals that annealing in a magnetic field of 3 kOe results in an anisotropic giant magnetoresistance (GMR) in the films. The anisotropic GMR features correlate to the magnetic anisotropy that develops during the magnetoannealing. The shape of GMR curves varies in the hard and easy field direction under temperatures of 400 and 300 degrees Celsius.

The magnetic thermal stability of Mn and Co volume-doped acicular [Gamma]-[Fe.sub.2][O.sub.3] particles was studied. These MnCo-[Gamma]-[Fe.sub.2][O.sub.3] particles with a coercivity about 950 Oe and Co content about 3.5 wt.% have been prepared by high temperature ion diffusing and step annealing. The MnCo-[Gamma]-[Fe.sub.2][O.sub.3] particles exhibit a much higher transverse field stability than that of Co-[Gamma]-[Fe.sub.2][O.sub.3] particles. The induced effective uniaxial anisotropy constant, [K.sub.u] and the magnetocrystalline anisotropy constant, [K.sub.1] of the particles were determined by the analysis of torque curves. The high magnetic thermal stability of these particles is mainly due to the higher and more stable induced uniaxial anisotropy, which is the result of the anisotropic arrangements of cobalt ions promoted by the presence of manganese ions during the step annealing. The MnCo-[Gamma]-[Fe.sub.2][O.sub.3] particles show a smaller irreversible decrease of uniaxial anisotropy with temperature and time in a magnetic field.

The microstructural and magnetic characteristics of Bi/Al/Mn/SiO multilayered structures were investigated using magnetic measurements. A new type of domain structure which was characterized by increasing ramified branches and conspicuous circular envelopes was reported. The results showed that these branches were associated with the magnetization orientations of the films.