Variable valve timing unit, which is able to decrease environmental load and improve fuel economy is loaded onto many automobiles recently. This unit consists mainly of sprocket, housing and rotor. These parts are requested different properties according to environment. We produce sintered parts for variable valve timing unit by selecting compact, sinter process and special treatment according to demanded properties. In this paper, demanded properties of sintered parts for variable valve timing unit and adopted technique to satisfy them are presented.

Thermoelectric conversion efficiency of thermoelectric elements can be increased by using a structure combining n-type and p-type semiconductors. From the above point of view, attention was directed at ZnO as a candidate n-type semiconductor material and investigations were made. As the result, a dimensionless figure of merit ZT close to 0.28 (1073K) was obtained for specimens produced by the PCS (Pulse Current Sintering) method with addition of specified quantities of , CoO, and to ZnO. It was found that the interstitial in the ZnO restrains the grain growth and CoO acts onto the bond between grains. The influence of the inclusion of and CoO onto the sintering behavior also was investigated.

The influence of the internal current for the ZnO ceramics on the sintering behavior by pulse current sintering (PCS) method was investigated. To clear the dependence of inner current on the sintering behavior of ZnO ceramics, direct measurement of electric resistance of ZnO specimen under sintering by SPS device was carried out. It was observed that electric resistance of specimen decreases with increase in the temperature. The electric resistance begins to decrease from the low temperature of . The internal structure of sintered ZnO ceramics changed by the control of the internal current in the specimen using plate.

Ru-C nano-composite films were prepared by MOCVD, and their microstructures and their electrode properties for oxygen gas sensors were investigated. Deposited films contained Ru particles of 5-20 nm in diameter dispersed in amorphous C matrix. The AC conductivities associating to the interface charge transfer between Ru-C composite electrode and YSZ electrolyte were 100-1000 times higher than that of conventional paste-Pt electrodes. The emf values of the oxygen gas concentration cell constructed from the nano-composite electrodes and YSZ electrolyte showed the Nernstian theoretical values at low temperatures around 500 K. The response time of the concentration cell was 900 s at 500 K.

More and more applications or demands for machine parts etc are expected for AISI 440C (hereinafter referred to as "440C") Stainless Steel because of its characteristic features, i.e. high-strength as well as high-corrosion resistance. This research has enabled us to obtain sintered products with good quality even under a wide range of temperature by utilizing the pinning effect of NbC, improving the relevant sintering feature of 440C Stainless Steel in the MIM method.

Austenitic stainless steel has been used as a corrosion resistance material. However, austenitic stainless steel has poor wear resistance property due to its low hardness. In this investigation, we apply powder composite process to obtain hard layer of Stainless steel. The composite material was fabricated from planetary ball milled SUS316L stainless steel powder and WC powder and then sintered by Pulsed Current Sintering (PCS) method. We also added TiC powder as a hard particle in WC layer. Evaluations of wear properties were performed by pin-on-disk wear testing machine, and a remarkable improvement in wear resistance property was obtained.

Image created by stack imaging spectral amplitudes based on the impact-echo (SIBIE) method is largely one-dimensional because a single frequency domain spectrum for wave reflected below a single point of impact is used to create the image. The method has limitations for representing defects in a cross section of a concrete structural element using two-dimensional coordinates. This study focused on defect detection and visualization in a concrete structural element using multiple impacts and accumulated SIBIE. An impactor was used to induce energy at multiple points at positioned at prescribed intervals along the structural element. A modified SIBIE method was applied to the collected data of each point and the modified SIBIE images were accumulated to generate one image (an accumulated SIBIE image). As a result, the defect positions could be represented in the cross section of the structural element using a two-dimensional coordinate system.

New food material "Rosa rugosa petal" with strong anti-oxidant activity We have recognized that administration of the flower of R. rugosa reduced the odor of mouse's feces. Thus, we supposed that it must be effective for human, and the effect was proved by the experiments of volunteer. Moreover, it was proved to be effective for aging odor of human. The effects must be due to anti-oxidative activities of R. rugosa. Ear wax was collected from volunteer, 50 year old or more, and the ether extract of the wax was analyzed by GC-MS for detection of 2-nonenal. 2-Nonenal was detected in the ear wax of few volunteers, but the administration of 2 capsules containing 100mg of R. rugosa per day reduced the 2-nonenal under detection limit. These results were patented in Japan(JP No.4008369), and a new company, Harunire bio laboratory Co., was established in Kitami Institute of Technology in 2003 for development of new products. The active constituents in R. rugosa supposed to be polyphenols, hydrolysable tannnins, such as rugosin A, tellimagrandin, and the contents of these polyphenols exceed more than 20% in dry flower of R. rugosa. The flower of R. rugosa was also shown to inhibit many enzymes, such as α-amylase and α-glucosidase, and prevent intestinal disorder. Various physiological activities are evaluated using isolated polyphenols now. Product development of new functional foods from onion (Sun Onion) The amount of onion production in the Abashiri-Kitami area is about 30% of Japan. Thus, the research for development of functional foods using onion was started for the increment of onion consumption. The following new results were obtained (JP No.3697524). The flavonoids in the juice and the squeezing residue resulted in process of onion juice manufacture were analyzed, and large amount of quercetin and its glycosides were shown to remained in the squeezing residue. The amounts of flavonoids in the residue are 5-10 times of those in the juice. Moreover, the squeezing residue contains insoluble dietary fibers, and it must be expected to improve of intestinal disorders. The irradiation of light (2500lux) on onion in artificial weather machine increased the amount of quercetin eight times. Thus, the new food material using the squeezing residue after the irradiation of sunlight, stronger than artificial light was developed. The amount of flavonoid (total quercetin) was shown to exceed 800mg/100g, and the amount of the pectin was about 10g/100g, these contents were extremely higher than those without irradiation. Moreover, α-glucosidase inhibitor was isolated from onion irradiated by sunlight, and the activity of irradiated onion was shown to be twice of that of without irradiation. Breeding of new onion rich in functional constituents We analyzed flavonoids by HPLC in 15 kinds of onions cultivated in Hokkaido Kitami Agricultural Experiment Station, and 15 kinds onions cultivated in Sapporo Agricultural Experiment Station. Total flavonoids contents of edible part of these onions were 24～293mg/100g, and those in outer peel were 265～5,613mg/100g. The onion breed with high flavonoids contents was discovered. The cultivation characteristic and the processing characteristic are now under investigation. In a human clinical trial, the R. rugosa petal was proven to decreased neutral fat (triglycerides). The R. rugosa petal must to be commercialized as the functional food and cosmetic product. In the case of sunlight onion, applications for vegetable juice and function food are under investigation.

A cDNA Fragment encoding iron storage protrin generated by polymerase chain reaction(PCR) using highly conserved regions of ferritin related genes were used to sereen a red pepper cDNA library. cDNA clone was designated as Fp1. Fp1 clone contatines a 5' nontranslated region of 51dp containing stop conds. Down stream from 5' UTP. an open reading frame of 750bp was observed. followed by a 3' UTR of 272bp. The deduces amino acid sequence of red pepper protein(Fp1) showed 84%, 48% and 36% identity with soybean(SolC). human(HuL H) and horse spleen(HoS-L) ferritin mRNA accumulation in response to iron. Ferritin mRNA accumulation was transient and particularly abundant in leaves. reaching a maxmum at 12h. The level of ferritin mRNA in roots was affected to a lesser extent than in leaves.

Total iron content and ferritin distribution have been determined in red pepper(Capsicum annuum L.) during development stage under conditions of iron nutritional status from hydroponic culture. Color of the leaves become chlorotic on iron deficient and high concentration. The plant height on each iron concentration had retarding effect at concentration lower than 25μM and greater than 12525μM. In normal green leaves. Total iron content was almost constant with a mean value of 2.5μmole of iron/mg of dry matter, except at 63day, for which it increases slightly to 4μmole. Howere, iron content of chlorotic plants grew on iron free medium was not almost detectable. Also in post chlorotic leaves(++Fe), iron content was evidently increase unitl 7days after transfer on liquid medium, but decreased from after 14days. Also, ferritin protein analysed total protein extracts prepared from leaves of different ages using antibodies raised against ferritin protein. Ferritin protein deereased progressively during the first week of germination and was not detectable in vegetative tissues. Ferritin protein in post chlorotic leaves wasevidently strongly cnhanced until 11days after transfer on liquid medium but decreased until the leves became chlorotic.