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B. N. Ganguly N. N. Mondal M. Nandy F. Roesch 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(2):685-698
Positron emission tomography (PET) is an imaging modality for medical diagnoses that can determine biochemical and physiological
processes in vivo in a quantitative way by using radio-pharmaceuticals labeled with positron emitting radionuclides. This
article brings together various aspects of the basic physics, critical design and instrumentation along with the modalities
of the application of radiotracers and the radiological protections involved in the processes. A critical discussion on the
various aspects of the PET system is also included. Several new advances and scope of future investigations in terms of better
sensitivity, local as well as kinetic resolution, specific tracer targeting (including chemical speciation) and better spatial
resolution of the PET image are also covered. 相似文献
74.
Arbain D Syafni N Friardi Putra DP Komala I Yamaguchi K Asakawa Y 《Natural product communications》2011,6(3):349-352
The Sumatran forest plants Lerchea cf. bracteata and L. parviflora were found to contain alkaloids and their extract showed siginificant activity toward some testing pathogenic microbes. Isolation work on L.cf bracteata yielded known quaternary alkaloid N(b)-methylantirhine (2) while L. parviflora gave 5,6-dihydroflavopereirine (3). 相似文献
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John Augustine Sandip Das Anil Maheshwari Sabhas C. Nandy Sasanka Roy Swami Sarvattomananda 《Computational Geometry》2013,46(3):340-357
A new class of geometric query problems are studied in this paper. We are required to preprocess a set of geometric objects P in the plane, so that for any arbitrary query point q, the largest circle that contains q but does not contain any member of P, can be reported efficiently. The geometric sets that we consider are point sets and boundaries of simple polygons. 相似文献
77.
Beneficial role of carbon nanotubes on mustard plant growth: an agricultural prospect 总被引:3,自引:0,他引:3
Anindita Mondal Ruma Basu Sukhen Das Papiya Nandy 《Journal of nanoparticle research》2011,13(10):4519-4528
Nowadays an increasing application of nanotechnology in different fields has arisen an extensive debate about the effect of
the engineered nanoparticles on environment. Phytotoxicity of nanoparticles has come into limelight in the last few years. However, very few studies have been done so
far on the beneficial aspects of nanoparticles on plants. In this article, we report the beneficial effect of multi-walled
carbon nanotubes (MWCNTs) having diameter of ~30 nm on Brassica juncea (mustard) seeds. Measurements of germination rate, T
50 (time taken for 50% germination), shoot and root growth have shown encouraging results using low concentration of oxidized
MWCNT (OMWCNT) treated seeds as compared to non-oxidized as well as high concentration OMWCNT treated seeds. For toxicity
study we measured the germination index and relative root elongation, while conductivity test and infra-red spectra were also
performed to study the overall effect of oxidized and non-oxidized nanotubes on mustard seeds and seedlings. 相似文献
78.
Chunlin Wu Xurong Qin Adhitya Mangala Putra Moeljadi Hajime Hirao Jianrong Steve Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(9):2731-2735
Copper complexes of monodentate phosphoramidites efficiently promote asymmetric arylation of N‐azaaryl aldimines with arylboroxines. DFT calculations and experiments support an elementary step of 1,4‐insertion in the reaction pathway, a step in which an aryl‐copper species adds directly across four atoms of C=N?C=N in the N‐azaaryl aldimines. 相似文献
79.
A multiwavelength Brillouin/erbium fiber laser (BEFL) with low threshold power is realized. A low threshold power of 3 mW and a wide tuning range of 18 nm can be achieved by controlling the reflected power in the nonlinear optical loop mirror (NOLM). Up to 24 lines with a wavelength spacing of 0.086 nm are generated at the Brillouin pump and at the 1 480-nm pump with 0.5 dBm (0.9 mW) and 25 mW of power, respectively. 相似文献
80.
Nandy Putra YanuarFerdiansyah N. Iskandar 《Experimental Thermal and Fluid Science》2011,35(7):1274-1281
Microprocessor power dissipation is constantly increasing. An increase in microprocessor size has also resulted in higher heat fluxes. The growth of information technology has rapidly increased over the past few years, causing an increase in the demand for a microprocessor that has a very high computing ability. The previous generation of central processing units (CPU) had 1.17 billion transistors planted in it, which indicates that a significant amount of heat was generated. The total heat dissipation resulting from a high end CPU is approximately 110-140 W, which will increase if the CPU voltage and frequency increase. Conventional air-cooled cooling systems are no longer adequate to remove these heat fluxes. For a number of applications, direct air-cooling systems will have to be replaced or enhanced by other high performance compact cooling techniques. In this study, the application of nanofluids as the working fluid on a heat pipe liquid-block combined with thermoelectric cooling is investigated. The type and effect of volume concentrations of nanofluids, coolant temperature, and thermoelectricsystem as heat pumps of a PC on the CPU’s temperature are considered. The results obtained from this technique are compared to those from other conventional cooling techniques. The heat pipe liquid-block combined with the thermoelectric system has a significant effect on heat transfer from the CPU. The higher thermal performance heat pipe liquid-block and thermoelectric cooled system with nanofluids proved its potential as a working fluid. 相似文献