Residential cool storage: peak load reduction alternatives

The authors investigate alternatives for achieving a peak load reduction in the residential airconditioning sector from a technical and economic point of view. Several thermal energy storage technologies are assessed, considering different types of houses and storage schemes. If the utility offered an incentive of $300-400/kW of deferred peak, residential thermal energy storage would have a short payback time for new installations. The payback time for retrofits is unacceptable. Two-stage evaporative coolers can reduce peak power by 60%, with an extra cost of about one-fifth that of new peaking facilities. They can totally replace conventional air conditioning in some climates without any loss of comfort. High efficiency air conditioners can also reduce peak power but their incremental cost over standard units is higher than that of new peaking facilities     

Motion analysis of grip and release with fingers using simple magnetic detection system

We have developed a magnetic grip-and-release motion detection system to measure time differences among fingers during motion. We designed a magnetic sensing system consisting of a magnetic oscillation coil, sensing coil, and circuit unit. We measured wave forms of grip-and-release motion (15 s) of seven healthy volunteers using the system. To provide the grip-and-release timing of each finger, we used the reference voltage of each subject in the state of grasping a rod with a 30 mm diameter. Using the reference voltage, the time differences in the finger movements of all volunteers were detected. The detected grip-and-release time difference of both dominant and nondominant hands had a main tendency in which the closing movement of the little finger is fast, within 10 ms, and the opening movement is slow, within 13 ms. Our data suggest that the new magnetic sensing system has the potential to detect the quantitative value of the time difference in grip-and-release motion among fingers.     

Sperm Proteases that May Be Involved in the Initiation of Sperm Motility in the Newt,Cynops pyrrhogaster

A protease of sperm in the newt Cynops pyrrhogaster that is released after the acrosome reaction (AR) is proposed to lyse the sheet structure on the outer surface of egg jelly and release sperm motility-initiating substance (SMIS). Here, we found that protease activity in the sperm head was potent to widely digest substrates beneath the sperm. The protease activity measured by fluorescein thiocarbamoyl-casein digestion was detected in the supernatant of the sperm after the AR and the activity was inhibited by 4-(2-aminoethyl) benzenesulfonyl fluoride (AEBSF), an inhibitor for serine or cysteine protease, suggesting the release of serine and/or cysteine proteases by AR. In an in silico analysis of the testes, acrosins and 20S proteasome were identified as possible candidates of the acrosomal proteases. We also detected another AEBSF-sensitive protease activity on the sperm surface. Fluorescence staining with AlexaFluor 488-labeled AEBSF revealed a cysteine protease in the principal piece; it is localized in the joint region between the axial rod and undulating membrane, which includes an axoneme and produces powerful undulation of the membrane for forward sperm motility. These results indicate that AEBSF-sensitive proteases in the acrosome and principal piece may participate in the initiation of sperm motility on the surface of egg jelly.     

Novel reworkable resins: thermo‐ and photo‐curable di(meth)acrylates

The aim of the study reported in this paper was to develop new di(meth)acrylates having aromatic units and thermally degradable units in their molecules. It was also the aim to clarify the photo‐curing and degradation properties of the new monomers. Di(meth)acrylates having aromatic units and thermally degradable units were synthesized. As thermally cleavable linkages, tertiary ester moieties were incorporated into the di(meth)acrylates. Three types of processes for curing and degradation of the cured resins were studied: thermal curing and thermal degradation; thermal curing and photodegradation; and photo‐curing and thermal degradation. In the thermal curing and photodegradation process, di(meth)acrylate films containing a thermally induced radical initiator and a photoacid generator (PAG) became insoluble in solvents on heating. The cured films became soluble in solvents after ultraviolet irradiation followed by baking. The re‐dissolution behaviors were strongly affected by the structures of the PAGs. A mechanism for the photo‐ or thermo‐curing and photoassisted thermal degradation was studied using Fourier transform infrared, ¹H NMR, thermogravimetric, mass spectrometric and size exclusion chromatographic analyses. Copyright © 2009 Society of Chemical Industry     

Control of secondary flow in a low solidity circular cascade diffuser

According to the previous experimental works on the low solidity circular cascade diffuser (LSD), a pressure recovery of a centrifugal blower was improved by the LSD significantly in a wide range of flow rate, and the pres-sure recovery was improved further by the LSD with a tandem cascade in comparison with the LSD with a sin-gle-row cascade. In the present study, the flow behavior in the LSD with the tandem cascade has been analyzed numerically by using the commercial CFD code of ANSYS-CFX12. It was shown clearly that the higher pressure recovery was achieved by applying the LSD with the tandem cascade, and the high pressure recovery is based on the high pressure rise in the vaneless space upstream of the LSD and the high blade loading of the front blade of the LSD. The high pressure recovery in the LSD could be achieved by controlling the flow separation on the suc-tion surface of the front blade and also on that of the rear blade due to formation of the favorable secondary flow and due to increase in mass flow passing through the slit section between the front and rear blades.     

Mass and size distribution of firebrands generated from burning Korean pine (Pinus koraiensis) trees

The present study reports on a series of real‐scale fire experiments that were performed to determine the mass and size distribution of firebrands generated from Korean Pine (Pinus koraiensis), a common conifer species indigenous to China, Japan, and Korea. The experiments were performed at the Building Research Institute in Tsukuba, Japan. The total tree height was fixed at 4.0 m and tree moisture content was varied to examine the influence that this parameter has on the mass and size distribution of the firebrands that are produced, under ambient wind conditions. The firebrands were collected using an array of pans. The pans used for firebrand collection were filled with water. This ensured that firebrands would be quenched as soon as they made contact with the pans. The firebrands were subsequently dried and the mass and size of more than 500 firebrands were measured. The Korean pine trees were also mounted on load cells during burning to determine the temporally resolved mass loss profiles. The mass loss data were used to compare the total amount of mass collected as firebrands with the total amount of mass burned. Results of this study are presented and compared with the mass and size distribution of firebrands collected from burning Douglas‐fir trees, a conifer tree species indigenous to the U.S.A. Copyright © 2008 John Wiley & Sons, Ltd.     

A Hydrogen Peroxide Activatable Gemcitabine Prodrug for the Selective Treatment of Pancreatic Ductal Adenocarcinoma

The main concern in the use of anticancer chemotherapeutic drugs is host toxicity. Patients need to interrupt or change chemotherapy due to adverse effects. In this study, we aimed to decrease adverse events with gemcitabine (GEM) in the treatment of pancreatic ductal adenocarcinoma and focused on the difference of hydrogen peroxide levels in normal versus cancer cells. We designed and synthesized a novel boronate-ester-caged prodrug that is activated by the high H₂O₂ concentrations found in cancer cells to release GEM. An H₂O₂-activatable GEM (A-GEM) has higher selectivity for H₂O₂ over other reactive oxygen species (ROS) and cytotoxic effects corresponding to the H₂O₂ concentration in vitro. A xenograft model of immunodeficient mice indicated that the effect of A-GEM was not inferior to that of GEM when administered in vivo. In particular, myelosuppression was significantly decreased following A-GEM treatment compared with that following GEM treatment.