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One new sterpurane sesquiterpene (1), named (3R,6S,7S,8R,10S)-3,7,14-trihydroxy-1-sterpurene was isolated from cultures of the basidiomycete Pholiota nameko. The structure of new compound was elucidated by extensive spectroscopic. Additionally, a single crystal X-ray diffraction not only confirmed the structure, but also determined the absolute configuration of the new compound. The compound was evaluated for cytotoxicity against five human cancer cell lines, but no significant cytotoxicity were found (IC50 values > 40 μM).

One new sterpurane sesquiterpene (

A novel welan gum-modified cellulose adsorbent was prepared through emulsification, regeneration, and modification. SEM and FTIR were used to characterize the modified cellulose adsorbent. The adsorption isotherms of metal ions on the adsorbent were well fitted by Langmuir model, with the maximum adsorption capacities of 83.6, 77.0, and 67.4 mg/g for Cd2+, Pb2+, and Cu2+, respectively. The adsorption kinetics was well described using the pseudo-first-order model. Moreover, the adsorption capacities for the three metal ions increased with the increase of temperature, and the optimal pH was 5. Furthermore, the thermodynamic analysis indicated that the adsorption processes were spontaneous and endothermic.

Based on a municipal highway tunnel in western China, for the building of the tunnel surface dense, especially import Portal Jude Biao most shallow depth of less than 10m building project, we proposed borehole layout, charge and detonate Network Road design method, and the corresponding control points of drilling and blasting operations and blasting safety control measures and means to ensure that the duration and quality of construction, can provide some experience of similar projects and basis.

Based on a tunnel in western China as a project, with high water pressure, water-rich, karst features and other projects, launched grouting water research, the cement-silicate slurry mixing method for determining the mixing ratio to ensure the effectiveness and construction safety grouting key factors, as well as the specific implementation grouting effect evaluation method has important theoretical and practical value for the design and construction of similar tunnels provide a reference.

Based on the comprehensive data collection of the status of operating highway tunnels’ leakage diseases in Chongqing area, this essay conducted statistical analysis on the leakage state of the typical tunnel with leakage disease. According to statistical rule, this essay builds up numerical simulation model and applies Finite difference method to study the security of the lining when the cracks appear in different parts and under the conditions with or without water. The results of this research can be applied to the control of the leakage disease of the tunnel in Chongqing area and maintaining in operating, and this can also provide a reference to the calculation of lining security and bearing capacity for these tunnels.

One city subway shield tunnel under-passing an existing bridge is analyzed, using the method of the three dimensional finite element analysis to simulate the process of excavating the left and right tunnel to get the data of the subsidence, lateral, stress of the bridge, besides the reaction of the upper structure of the bridge when the shield machine thrusting ahead. The results of the study show that the overall settlement value of the pier is not big, but around piers on both sides, the maximum lateral come to 2.6 mm, and the maximum tension, compression stress of the bridge foundation increased by 1.07MPa and 0.4MPa, and arch structure in construction process stress adverse, it is suggested that we should reinforce the soil around the tunnel treatment to control the bridge foundation of uneven settlement, and at the same time, the process of closely monitor the situation of arch bridge.

An even-mode power combining technique was developed for a high-performance K-band push-push voltage control oscillator (VCO) in standard 0.18 m CMOS technology. The VCO was designed based on linear time variant (LTV) phase noise model. The obtained frequency tuning range and maximum output power were 1.95 GHz and 9.68 dBm with core power consumption of 3.6 mW at maximum oscil- lation frequency of 26.7 GHz. The push-push VCO demonstrated a phase noise of 117.5 dBc/Hz at 1 MHz offset, which resulted in an excellent FoM of 199.82 dBc/Hz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 3242-3246, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop. 23917

A Ka-band push-push oscillator and a Ku- band fundamental oscillator designed using GaAs pHEMT 0.15 mum technology are reported in this paper. The use of finite ground CPW structure that enhanced Q value of the passive element and improved the phase noise with the value of -113.2 dBc/Hz at 1 MHz offset of the push-push oscillator. The push-push oscillator achieves an oscillating frequency of 30.3 GHz while exhibiting a maximum output power of -1.5 dBm with the DC power consumption of 29 mW, together with a figure-of-merit (FOM) of -188.2 dBc/Hz at 1 MHz offset.