LEAST COST WORLD TRADE PATTERNS FOR GRAINS AND MEATS

International Relations/Trade,

Ignition of dust dispersions by shock waves

Imperial Users onl

High-Power and Low-Noise Circuit Techniques for Wideband RF, Millimeter-Waves and Optical Wireline Systems in Advanced RFSOI Technologies

The inevitable migration to deeply-scaled technology nodes forces special considerations on high-power, low-noise, and high spectral purity integrated circuits. The dissertation addresses these considerations for a wide spectrum of RF, mm-waves, and optical-wireline circuits in advanced CMOS SOI technologies. The major contributions are in distributed power amplifiers (DPAs), optical drivers, RF and mm-wave voltage controlled oscillators (VCOs), mm-waves low-noise amplifiers (LNAs), and high linearity mixers. The work in power amplifiers culminated in the design and measurement of several novel ultra-wide-band DPAs/drivers with 100+GHz of bandwidth (BW) in GlobalFoundries 45nm RFSOI technology. Several design techniques are introduced to break the gain-bandwidth (GBW), and power-BW trade-offs in conventional distributed designs. The first PMOS-only DPA with 100+GHz BW is demonstrated exploiting the decreasing gap between NMOS and PMOS performance in deeply-scaled technology nodes. Transistors stacking is exploited for high power while introducing two new stack compensation techniques, the multi-drive intra-stack and inter-stack coupling. Improved stability coupling networks and magnetic field confining transmission lines are also devised to allow high gain stable operation. Over 4.5 THz GBW is recorded from a cascaded DPA and over 100 Gb/s is measured in both 64-QAM and PAM-4 modulations for a CMOS modulator driver.The mm-wave 5G LNAs contributions focus on K/Ka bands designs for next generation phased-array systems and exploits the body-bias of fully depleted SOI devices to control the linearity and gain of LNAs in 22nm FDSOI technology.The efforts in RF and mm-waves LC VCOs focus on implementations in deeply scaled 22nm FDSOI technology node. New circuit techniques are proposed to allow ultra-low-voltage operation (sub 0.1 V), low flicker noise variability across the tuning range without a dedicated tuning for the common-mode, ultra-low phase noise while using thin-oxide only devices, and over 70% of tuning range spanning the X and Ku-bands.The work in high linearity mixers exploits the enhancement of the figure of merit of CMOS switches in new technology nodes, to implement all-passive 16-path harmonic-reject mixers with watt-level IIP3 and over 35 dBc harmonic rejection ratio for all harmonics up to 3 GHz

High-Power and Low-Noise Circuit Techniques for Wideband RF, Millimeter-Waves and Optical Wireline Systems in Advanced RFSOI Technologies

The inevitable migration to deeply-scaled technology nodes forces special considerations on high-power, low-noise, and high spectral purity integrated circuits. The dissertation addresses these considerations for a wide spectrum of RF, mm-waves, and optical-wireline circuits in advanced CMOS SOI technologies. The major contributions are in distributed power amplifiers (DPAs), optical drivers, RF and mm-wave voltage controlled oscillators (VCOs), mm-waves low-noise amplifiers (LNAs), and high linearity mixers. The work in power amplifiers culminated in the design and measurement of several novel ultra-wide-band DPAs/drivers with 100+GHz of bandwidth (BW) in GlobalFoundries 45nm RFSOI technology. Several design techniques are introduced to break the gain-bandwidth (GBW), and power-BW trade-offs in conventional distributed designs. The first PMOS-only DPA with 100+GHz BW is demonstrated exploiting the decreasing gap between NMOS and PMOS performance in deeply-scaled technology nodes. Transistors stacking is exploited for high power while introducing two new stack compensation techniques, the multi-drive intra-stack and inter-stack coupling. Improved stability coupling networks and magnetic field confining transmission lines are also devised to allow high gain stable operation. Over 4.5 THz GBW is recorded from a cascaded DPA and over 100 Gb/s is measured in both 64-QAM and PAM-4 modulations for a CMOS modulator driver.The mm-wave 5G LNAs contributions focus on K/Ka bands designs for next generation phased-array systems and exploits the body-bias of fully depleted SOI devices to control the linearity and gain of LNAs in 22nm FDSOI technology.The efforts in RF and mm-waves LC VCOs focus on implementations in deeply scaled 22nm FDSOI technology node. New circuit techniques are proposed to allow ultra-low-voltage operation (sub 0.1 V), low flicker noise variability across the tuning range without a dedicated tuning for the common-mode, ultra-low phase noise while using thin-oxide only devices, and over 70% of tuning range spanning the X and Ku-bands.The work in high linearity mixers exploits the enhancement of the figure of merit of CMOS switches in new technology nodes, to implement all-passive 16-path harmonic-reject mixers with watt-level IIP3 and over 35 dBc harmonic rejection ratio for all harmonics up to 3 GHz

Poly (acrylonitrile-co-methyl methacrylate) nanoparticles: I. Preparation and characterization

This work concerns the preparation and characterization of poly (acrylonitrile-co-methyl methacrylate) Copolymer, P(AN-co-MMA), nano-particles using precipitation polymerization technique. Potassium per-sulfate redox initiation system was used to perform polymerization process in an alcoholic aqueous system. The impact of different polymerization conditions such as comonomer concentration and ratio, polymerization time, polymerization temperatures, initiator concentration and co-solvent composition on the polymerization yield and particle size was studied. Maximum polymerization yield, 70%, was obtained with MMA:AN (90%:10%) comonomer composition. Particle sizes ranging from 16 nm to 1483 nm were obtained and controlled by variation of polymerization conditions. The co-polymerization process was approved by FT-IR and TGA analysis. The copolymer composition was investigated by nitrogen content analysis. Copolymers with a progressive percentage of PAN show thermal stabilities close to PAN Homopolymer. SEM photographs prove spherical structure of the produced copolymers. The investigated system shows promising future in the preparation of nanoparticles from comonomers without using emulsifiers or dispersive agents

Non-mastoidectomy Cochlear Implant Approaches: A Literature Review

Abstract Introduction Posterior tympanotomy approach for cochlear implant (CI) surgery, has been the most commonly used worldwide with current 0.7% rate of facial nerve injury. Non-mastoidectomy CI approaches include the suprameatal approach (SMA) and its modifications, the transcanal approach and its modifications and the pericanal approach for electrode insertion. Objectives The objective of this study was to review the literature regarding nonmastoidectomy CI approaches. Data Synthesis A search was performed in the LILACS, MEDLINE, SciELO, PubMed databases and Cochrane Library in February 2015, and the key words used in the search were CI, SMA, transcanal approach, pericanal approach, or electrode extrusion. About 30 studies that met the criteria described in "Study Selection" were read in full. The studies showed 1014 patients that underwent CI by SMA or its modifications, 266 CI patients treated by transcanal approach or its modifications, and 15 patients implanted by the pericanal approach. Reported complication with SMA was 99 (9.8%) minor and 13 (1.3%) major. With transcanal, there were 24 complications; 19 (7.1%) minor and 5 (1.9%) major. No post-operative complication was reported in pericanal approach. Studies showed no reported facial nerve paresis or paralysis in all non-mastoidectomy approaches. Conclusion Complications rates with non-mastoidectomy approaches are similar to those found in the mastoidectomy approach. Thus, non-mastoidectomy approaches may be an alternative in cases where the conventional mastoidectomy approach is difficult to perform. It would be helpful for CI surgeons to become familiarized with these approaches