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Humite-group minerals play a crucial role in transporting water and fluorine to the Earth’s deep mantle through slab sinking. In this study, we have used Brillouin scattering to determine the single-crystal elastic constants of four natural humite-group minerals with varying H2O and fluorite contents under ambient conditions, including one chondrodite [Mg4.88Si1.94O8(OH0.78F1.22)] (F61-Chn), one humite [Mg7.03Si3.07O12(OH1.26F0.74)] (F37-Hu), and two clinohumite [Mg8.85Ti0.19Si3.93O16(OH1.11F0.89) and Mg8.63Fe0.10Ti0.24Si3.97O16(OH1.84F0.16)] (F45-Chu and F8-Chu) samples. The adiabatic bulk (KS0) and shear (G0) moduli calculated from the elastic constants using Voigt-Reuss-Hill averages are: KS0= 120.4(3) GPa and G0= 74.1(5) GPa for F61-Chn, KS0= 122.4(3) GPa and G0= 78.4(2) GPa for F37-Hu, KS0= 126.2(3) GPa and G0= 79.7(2) GPa for F45-Chu, and KS0= 120.5(3) GPa and G0= 76.8(2) GPa for F8-Chu. Our results indicate that the addition of F leads to a noticeable increase in the elasticity of clinohumite and chondrodite, which is in contrast to the effect of H2O. Although Fe has a negligible effect on the bulk modulus of clinohumite, it can produce a substantial decrease in the shear modulus. These results provide important insights into the influence of humite-group minerals on the mantle velocity structure. Furthermore, we have investigated the effects of composition on the elasticity and sound velocities of minerals along the forsterite-brucite join in the MgO-SiO2-H2O system, confirming previous observations. Increasing H2O content along the forsterite-brucite join leads to apparent reductions in the elasticity and sound velocities. The influence of Fe on the elasticity and sound velocities of these minerals has also been evaluated.

Aluminum/Polytetrafluoroethylene (Al/PTFE) is a representative energetic material, which can be used in many fields including defense weapon fragments, insensitive penetrator or oil-well perforation. However, the insufficient mechanical strength of traditional ingredient has seriously restricted its penetration ability, and traditional additives improve its compressive strength at the expense of reactivity. Hence, innovative component design and advanced manufacturing technology should be applied to Al/PTFE composite. In this investigation, TiH2as a new reinforcement is introduced into Al/PTFE to improve both strength and reactivity. Quasi-static and dynamic compressive tests were conducted, and the impact reaction process was recorded by high-speed camera. The results shown Al/PTFE/TiH2composites are all elasto-plastic materials, significant strain hardening and strain rate hardening phenomenon were observed. The compressive strength increased first and then decreased with increase in TiH2content, reached the maximum of 185.1 MPa at the strain rate of 5000 s−1when TiH2content was 30 %, which increased by 30.4 % compared to traditional Al/PTFE. A newly-developed drop-weight device was used to quantitatively characterize reactivity, and the reaction efficiency reached 8.2 % when TiH2content was 30 %, increased by 43.2 % compared to Al/PTFE. The formation of oriented PTFE nano-fibers was considered the important strengthening mechanism. The established Johnson–Cook model was agreed well with experimental results. Combining the results of thermogravimetry-differential scanning calorimetry (TG-DSC) tests with X-ray diffraction (XRD) analysis of reaction residues, the reaction mechanism was clarified. The impact initiation reaction was in a mechano-chemical manner and the reactivity was speculated to be the results of multiple actions between Al/PTFE and TiH2.

A low value of Schottky barrier height (SBH) ( $\Phi _{B}{)}$ is highly desired to further reduce the power loss in 4H-SiC junction barrier Schottky (JBS) diodes; however, the reduced $\Phi _{B}$ results in serious leakage current ( ${I}_{R}{)}$ when blocking high voltages. In this work, a tunable low $\Phi _{B}$ of 0.92–0.98 eV with an ideal factor ${n}$ = 1.02–1.03 was first realized through effectual rapid thermal annealing (RTA) methods and combined with a trench-assisted stage-style p-type implants taking advantage of dead region for current flow to resolve the ${I}_{\text {R}}$ issue. Numerical simulation demonstrated the superiority of this promising strategy in alleviating the Schottky interface electric field ( ${E}_{\text {S}}{)}$ and suppressing ${I}_{R}$ without constraining the forward current flow. Based on this practical strategy, the fabricated device achieved one order of magnitude less ${I}_{R}$ at 25 °C and 220% enhancement of breakdown voltage ( ${V}_{B}{)}$ at 175 °C in contrast to the conventional low-barrier one. In addition, benefiting from the low $\Phi _{B}$ , the device achieved an ultralow turn-on voltage of 0.47 eV and a remarkable forward voltage drop ( ${V}_{F}{)}$ of 1.36 V extracted at 20 A, indicating 14% lower conduction loss than the titanium-based JBS diodes with the same device configuration. This novel device structure incorporating low-barrier Schottky contact metal and trench-assisted stage-style p-implants (SPs) in the dead region of current flow suggests a promising way to develop more advanced 4H-SiC JBS diodes in the future.

Spontaneous conversion of aspartic acid (Asp) to isoaspartic acid (isoAsp) is a ubiquitous modification that influences the structure and function of proteins. This modification of Asp impacts the stability of biotherapeutics and has been linked to the development of neurodegenerative diseases. We explored the use of 193 nm ultraviolet photodissociation (UVPD) to distinguish Asp and isoAsp in the protonated and deprotonated peptides. The differences in the relative abundances of several fragment ions uniquely generated by UVPD were used to differentiate isomeric peptide standards containing Asp or isoAsp. These fragment ions result from the cleavage of bonds N-terminal to Asp/isoAsp residues in addition to the side-chain losses from Asp/isoAsp or the losses of COOH, CO2, CO, or H2O from y-ions. Fragmentation of Asp-containing tryptic peptides using UVPD resulted in more enhanced w/w+ 1/y– 1/xions, while isoAsp-containing peptides yielded more enhanced y– 18/y– 45/y– 46 ions. UVPD was also used to identify an isomerized peptide from a tryptic digest of a monoclonal antibody. Moreover, UVPD of a protonated nontryptic peptide resulted in more enhanced yions N- and C-terminal to isoAsp and differences in b/yion ratios that were used to identify the isoAsp peptide.

In this article, we propose the use of p-type retrograde implants (RPs) for enhanced device performance and alleviated temperature dependence of leakage current in 4H-SiC junction barrier Schottky (JBS) diodes. Two 1200-V JBS diodes consisting of optimized RP have been designed, fabricated, and characterized. The RP offers the following merits for JBS: 1) deeper p-n junction to reduce electric field at the Schottky interface; 2) more width of the space charge zone to decrease capacitance; 3) more depletion region in the p-type unit to partly undertake blocking voltage; and 4) higher doping of subsurface region to address the reach-through issue. The fabricated RP devices yielded a remarkable enhancement of an ultralow ${V}_{F} \cdot {Q}_{C}$ to be 144.5 $\text{V}\cdot $ nC (1.53 V $\times94.3$ nC) at 20-A rated current, which might be the reported lowest one to the best of our knowledge. What is more, the RP-JBS diodes could realize a leakage current ( ${I}_{R}$ ) of 0.2 $\mu \text{A}$ at 1200 V and maintain an extremely low level of 6.0 $\mu \text{A}$ even at 175 °C, with just 5.8- $\mu \text{A}$ increasement over the temperature range of −50 °C to 175 °C. Compared with the latest commercial JBS products from leading companies, the RP-JBS diode has shown its significant capability of mitigating the impact of rising temperatures on device performance. In particular, only 8.4% roll-off of breakdown voltage ( ${V}_{B}$ ) extracted at 50 $\mu \text{A}$ was obtained. The superior performance of the 4H-SiC JBS diodes with RP makes the device a promising candidate for high-temperature, high-voltage, and high-frequency applications.

To improve the combustion performance of ammonium perchlorate (AP), more high-performance combustion catalysts need to be developed. In this paper, five new types of energetic coordination complexes were prepared by combining 3-aminofurazan-4-carboxylic acid (AFCA) with transition metals (Co, Ni, Fe, Cu, and Mn). The structures were determined by single-crystal X-ray diffraction. Differential scanning calorimetry and thermogravimetric analysis were performed to characterize the thermal stability of the complexes. The five complexes exhibit superior energy properties to traditional explosive TNT. The thermal stability of the complexes was improved to a certain extent after binding to the metal. Catalytic experiments were performed by adding 10 wt % complexes to AP with differential thermal analysis instruments. Results indicate that the best catalyst is manganese as the metal center, which decreases the high-temperature decomposition (HTD) peak of AP by 133.3 °C and the activation energy (E) of AP by 102.2 kJ/mol and increases the mixture heat release by more than four times. Thermogravimetric analysis-Fourier transform infrared spectroscopy was applied to monitor the process of catalyzing AP, which indicates that the HTD of AP was advanced substantially. The combustion experimental results show that AP with complex 4and complex 5can burn vigorously. Overall, the furazan-based complex catalysts we synthesized have a good catalytic potential for solid propellant.

In this study, we have determined the single‐crystal elasticity of clinohumite [Mg8.85Ti0.19Si3.93O16(OH1.11F0.89)] using Brillouin measurement up to 21 GPa at 300 K and 1 bar at 750 K, respectively. The elasticity of clinohumite was determined to be KS0= 126.2(3) GPa, G0= 79.7(2) GPa with pressure derivatives KS′ = 4.2(1), G′ = 1.3(1), pressure derivatives ∂KS/∂T= −0.024(1) GPa/K, and ∂G/∂T= −0.011(1) GPa/K). We comprehensively examined the effects of varying H2O, fluorine content and thermal states, on the velocity and density structures of the subducted harzburgite layer. Assuming a typical H2O content of 2 wt.% within harzburgite, our modeling has shown that hydrous harzburgite with clinohumite as the decomposition product of serpentine along a hot slab geotherm even has the VPand VS0.4–0.8(6)% greater than it dry counterpart at 250–380 km depth. Yet in the top transition zone, the addition of H2O and F can effectively lower the sound velocities and density. The F‐bearing hydrous harzburgite has the VPand VS1.1(5)–1.3(3)% lower than its dry counterpart, and only 0.6(5)% and 2.3(5)% greater than the pyrolitic mantle. Along cold slab geotherm, phase A will replace clinohumite as the dominant hydrous phase in the harzburgite, the VPand VSare 4.8(5)–5.3(3)% and 5.9(5)–6.0(3)% greater than the pyrolitic mantle in the upper mantle. In the top transition zone, the difference is approximately 3% in VPand 5% in VS. Our results provide crucial experimental evidence for future assessments of the seismic signals of subducted slabs with different hydrous minerals and thermal states. Subducted slab plays a crucial role in connecting the Earth's surface to the interior. Transportation of H2O and other important volatiles to the Earth's mantle via subducted slab can greatly influence a series of physical properties of mantle minerals. Clinohumite is one of the most important H2O and fluorine (F) carriers in the subducted slab. Here, we determined the single‐crystal elasticity of F‐bearing clinohumite at high pressures and temperatures. The obtained elasticity data were applied to model the velocity profiles of the hydrous harzburgite. Our results show that the addition of H2O and F can enhance the velocity difference between harzburgite and pyrolitic mantle at 250–380 km depth along the hot slab geotherm, and VPand VSof harzburgite with 2 wt.% H2O and clinohumite as the H2O‐bearing phase are 0.4–0.8(6)% greater than those of dry harzburgite. In the transition zone depth, addition of H2O and Fe lowers the sound velocities of harzburgite. Hydrous harzburgite has a lower VPand VSthan its corresponding dry phase. These new velocity constraints can help us better understand the circulation of H2O and F within Earth's interior and identify the detected seismic observations of subducted slabs with different compositions and thermal states. Single‐crystal elasticity of F‐bearing clinohumite was determined to 21 GPa and 750 K and shows strong dependence with F contentThe obtained results were used to model the velocity profiles of the hydrous harzburgite layer considering the thermal state and compositionH2O and F in clinohumite have significant influence on the velocity profile of subduction slab Single‐crystal elasticity of F‐bearing clinohumite was determined to 21 GPa and 750 K and shows strong dependence with F content The obtained results were used to model the velocity profiles of the hydrous harzburgite layer considering the thermal state and composition H2O and F in clinohumite have significant influence on the velocity profile of subduction slab

We have developed a methodology for the greatly efficient construction of significant 2,3-dihydrobenzofuran scaffolds bearing a quaternary carbon center at the C2 position by means of [4 + 1] annulation reactions between p-quinone methides and α-aryl diazoacetates as C1 synthons through organocatalysis by readily accessible TfOH catalyst under mild and transition metal-free conditions. This metal-free protocol furnishes an operationally simple and swift process for the free assembly of diverse highly functionalized 2,3-dihydrobenzofurans and also features broad substrate scope, excellent functional group compatibility, and environmental friendliness. Mechanistic investigation suggested that the reaction undergoes a rapid cascade protonation/intermolecular Michael addition/intramolecular substitution process.

Graphitic carbon nitride quantum dots (CNQDs) are a new class of nanomaterial with an extraordinary photoluminescent property. Here, three highly water-soluble and photoluminescent CNQDs are synthesized through a green and facile one-step hydrothermal approach, with urea as the nitrogen source and citric acid and its salts as carbon sources. The photoluminescence (PL) performance demonstrated that the fluorescence emission peak was altered by neither the structures nor the molar ratio of urea to the carbon source. Three highly luminescent CNQDs with a quantum yield of 40% were obtained when the molar ratio of urea to sodium citrate, citric acid, and ammonium citrate was 6:1, 18:1, and 18:1, which have average sizes of 4.1, 4.6, and 6.3 nm, respectively. Moreover, the possibility of using CNQDs as potential probes to determine the concentration of iron is also discussed. The results show that the as-prepared CNQDs has high selectivity for Fe3+ions. The quenching mechanism of CNQDs by iron is connected with the nitrogen functional groups on the surface of CNQDs. Results showed valuable information about the effects of the carbon source on the PL efficiency, biocompatibility, and metal ion detection properties of CNQDs.

In the field of electronics, organocatalysts are in high demand for use in the synthesis of clean polymers using solar radiation rather than potentially contaminating metals. Combining theoretical design, simulation, and experiments, this work presents a novel, pyridine-diketopyrrolopyrrole (P-DPP)-based metal-free visible-light organophotoredox catalyst (P-DPP). It is effective in the photocontrolled organocatalytic atom-transfer radical polymerization (O-ATRP) of methyl methacrylate (MMA) and styrene. The use of this catalyst and white light-emitting diode (LED) irradiation produces polymers with a cross-linked feature. In O-ATRP, the P-DPPcatalyst has an oxidative quenching catalytic mechanism with an excited-state reductive potential of −1.8 V, fluorescence lifetime of 7.5 ns, and radical-cation oxidative potential of 0.45 V. Through molecular simulation, we found that the adjacent pyridine group is key to reducing the alkyl halide initiator and generating radicals, while the diketopyrrolopyrrole core stabilizes the triplet state of the catalyst through intramolecular charge transfer. The findings related to this novel photoredox catalyst will aid in the search for much more effective organophotoredox catalysts for use in controlled radical polymerization. They will also be of value in the fields of polymer chemistry and physics and in various applications.

The special linear dioxo cation structure of the uranyl cation, which relegates ligand coordination to an equatorial plane perpendicular to the O═U═O vector, poses an unusual challenge for the rational design of efficient chelating agents. Therefore, the planar hexadentate ligand rational design employed in this work incorporates two bidentate catecholamine (CAM) chelating moieties and a flexible linker with a β-dicarbonyl chelating moiety (β-dicarbonyl(CAM)2ligands). The solution thermodynamics of β-dicarbonyl(CAM)2with a uranyl cation was investigated by potentiometric and spectrophotometric titrations. The results demonstrated that the pUO22+values are significantly higher than for the previously reported TMA(2Li-1,2-HOPO)2, and efficient chelation of the uranyl cation was realized by the planar hexadentate β-dicarbonyl(CAM)2. The efficient chelating ability of β-dicarbonyl(CAM)2was attributed to the presence of the more flexible β-dicarbonyl chelating linker and planar hexadentate structure, which favors the geometric arrangement between ligand and uranyl coordinative preference. Meanwhile, β-dicarbonyl(CAM)2also exhibits higher antiradical efficiency in comparison to butylated hydroxyanisole. These results indicated that β-dicarbonyl(CAM)2has potential application prospects as a chelating agent for efficient chelation of a uranyl cation.

The objection detection of panoramic image is the key part of street view, intelligent transportation, automatic driving and other technologies. Due to the shortcomings of existing algorithms in detecting panoramic images, firstly a high-resolution panoramic image dataset is introduced, then the multi-scale feature pyramid networks (MS-RPN) structure is proposed and a new network with Sim-Inception module is designed. The network can extract different scales of objects from different feature layers, so that the small object in the image can also be accurately detected. Finally, the entire detection network is trained by using the dataset constructed in this study. Meanwhile, the ROIPool is replaced by ROIAlign and the loss function is adjusted according to the network structure. The experimental results show that the detection performance on the panoramic dataset is significantly improved by authors’ proposed algorithm, which is better than other deep learning algorithms, especially for small object in the image.

In ultra-precision machining field, the air motorized spindle which is composed of a motor and an air bearing, plays a major role. In air motorized spindle, the motor eccentricity between the stator and the rotor is inevitably introduced during the manufacturing process, which directly affects the machining results of workpiece surface, and this phenomenon is particularly unwanted in machining. However, little attention has been paid to the motor eccentricity of air motorized spindle. In this paper, a new integrated electromechanical coupling method for estimating unbalanced force in air motorized spindle is presented, and the effects of motor rotor eccentricity on surface topography in ultra-precision processes are analyzed. An electromagnetic-mechanical method is used to study the coupling effects between the motor rotor and the aerostatic spindle. Meanwhile, the motor rotor and the aerostatic spindle are analyzed as a whole. In order to clearly describe the electromagnetic–mechanical method, the ultra-precision spindle for potassium dihydrogen phosphate crystal machining tool is selected as the research object, and the model of air motorized spindle and motor rotor eccentricity are presented. Besides, in order to assess the impact of the radial magnetic force caused by motor rotor eccentricity on the spindle performance, a range of rotor eccentricities is calculated. Additionally, the influence of the motor rotor eccentricity on the dynamic response of spindle is further analyzed. It is found that motor rotor eccentricity has a significant influence on the spindle vibration, which dramatically reduces the processing quality. Finally, the machining experiments are carried out, and the flatness errors of the workpiece caused by the motor rotor eccentricity are obtained by the wavelet method. The experimental results are consistent with the analysis results, which verifies the reliability of this method. This study is quite meaningful for deeply understanding the influence of motor rotor eccentricity on the machined surface.

The two-dimensional discrete dislocation dynamics simulations under fully periodic boundary conditions has been employed to study the dislocation pattern evolution in the early stages of fatigue in aluminium single crystal. Long-range force among of dislocations is solved by line elasticity model, and short-range force is obtained by constitutive equations of dislocation nucleation, slip, pileup and annihilate. Dislocation movement mechanisms of single-slip-oriented and multi-slip systems are simulated and the evolution process of fatigue pattern is revealed. The result shows that dislocation quantity and microstructure strongly depend on external load and internal configuration. The dislocation pattern of single-slip-oriented generate matrix wall, and positive dislocations are vertical alignment and negative dislocations are at the angle of 45° with slip oriented in the initial stage. For multi-slip system, maze structure of dislocations is produced during dislocation multiplication, which eventually transforms into persistent slip band. The result is consistent with the existing experiment.

A novel Ni-Co atomic pairs was theoretically screened out for improving electrochemical CO2reduction reaction, and demonstrated the great potential as highly efficient catalysts, provides a useful strategy to design heteronuclear DACs.

To investigate the correlation of the incidence of acute radiation-induced enteritis with the factors of patient treatment position and body mass index (BMI) in cervical cancer patient treated with the volumetric modulated arc therapy (VMAT) radiotherapy.

The frequency of harmful algal blooms (HABs) has been increasing dramatically since the 1970's in Chinese coastal waters, accompanied by a change of the composition of harmful algae. In this review, a list of causative species of HABs, some of which have been detected for the first time in this area, is provided. 12 main HAB species, including their morphological characteristics, their taxonomy as well as their ecology and impact, are illustrated in detail. Possible factors that are responsible for the shift of causative species of HABs are discussed. The development of HAB causative species in Chinese coastal waters deserves more attention and efforts in HAB monitoring and in HAB management in the future.

An advanced two-dimensional liquid chromatography/mass spectrometry platform was used to quantify individual host cell proteins (HCPs) present at various purification steps for several therapeutic monoclonal antibodies (mAbs) produced in Chinese hamster ovary cells. The methodology produced reproducible identifications and quantifications among replicate analyses consistent with a previously documented individual limit of quantification of ~13 ppm. We were able to track individual HCPs from cell culture fluid to protein A eluate pool to subsequent viral inactivation pool and, in some cases, further downstream. Approximately 500 HCPs were confidently identified in cell culture fluid and this number declined progressively through the purification scheme until no HCPs could be confidently identified in polishing step cation-exchange eluate pools. The protein A eluate pool of nine different mAbs contained widely differing numbers, and total levels, of HCPs, yet the bulk of the total HCP content in each case consisted of a small subset of normally intracellular HCPs highly abundant in cell culture fluid. These observations hint that minimizing cell lysis during cell culture/harvest may be useful in minimizing downstream HCP content. Clusterin and actin are abundant in the protein A eluate pools of most mAbs studied. HCP profiling by this methodology can provide useful information to process developers and lead to the refinement of existing purification platforms.

Abstract: Previous studies found intraspecific diversity in Scrippsiella trochoidea A. R. Loeblich III, a widely distributed calcareous cyst-producing dinoflagellate. In this study, three strains (ST-1, ST-D6 and ST-K) of S. trochoidea isolated from the East Asian waters were studied, together with other geographical strains, to resolve their phylogenetic relationships. For the three East Asian isolates, two highly diverse regions of nuclear-encoded ribosomal DNA (rDNA), the 5.8S rDNA and its flanking internal transcribed spacers 1 and 2, and the 5′ portion of the large-subunit rDNA (encompassing the “D1“ and “D2” domains) were sequenced. Homologous sequences from other geographical isolates were selected from the GenBank database and the phylogenetic relationships were inferred from the molecular data of these strains. Strains of S. trochoidea were found to cluster into three major clades (STR1, STR2 and STR3), as reported in previous studies. Two of the three strains ST-1 and ST-K, were grouped in clade STR2, the other strain, ST-D6, belonged to clade STR3. The intraspecific diversity of S. trochoidea in East Asian waters makes it necessary to carry out phylogenetic investigations in combination with data of biogeography, population dynamics, and life cycle on the ecophysiology of a region.

There has been a rapid improvement in SiC materials and power devices during the last few years. SiC unipolar devices such as Schottky diodes, JFETs and MOSFETs have been developed extensively and advantages of insertion of such devices in power electronic systems have been demonstrated [1, 2]. However, unipolar devices for high voltage systems suffer from high drift layer resistance that gives rise to high power dissipation in the onstate. For such applications, bipolar devices are preferred due to their low onresistance. In this article, the physics and technology of SiC bipolar devices, namely Bipolar Junction Transistors BJTs, Insulated Gate Bipolar Transistors IGBTs, and Gate Turn Off Thyristors GTOs, are discussed. A detailed review of the current status and future trends in these devices is given with an emphasis on the device design and characterization. © 2009 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim

Asymmetric-structure perylene diimide (PDI) supramolecular photocatalysts were successfully constructed to induce robust internal electric field for efficient photocatalytic activity. Benefitting from the large dipole moment of the asymmetric-structure PDI, the internal electric field has been significantly enhanced by 8.4 times. And then the charge separation efficiency of the asymmetric-structure PDI has been dramatically improved by 2.4 times from 4.60% up to 11.22%. Thus, the asymmetric-structure PDI supramolecular presents evidently enhanced photocatalytic degradation performance, up to 4.8 times, even surpassing many reported high-activity organic photocatalysts. Meanwhile, they also exhibited a maximum 9.5-fold increase in photocatalytic hydrogen peroxide production activity. Briefly, this work throws light on enhancing the internal electric field via molecular structure modification to dramatically improve the photocatalytic performance.

Porous silicon powder and silica gel particles have been applied as inorganic matrices for the analysis of small molecules in matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐TOFMS). In contrast to conventional MALDI‐TOFMS, the signal interference of low‐molecular analytes by the matrix has been eliminated. Almost no fragmentations of the analytes were observed. Effects of various factors, such as the particle and pore size, the suspending solution, and sample preparation procedures, on the intensity of mass spectra have been investigated. The pore structure of the inorganic matrix and penetration of the analytes into the pores must be optimized for effective desorption and ionization of the analytes. Matrices (DHB and HCCA) were covalently bound to silica gel for improvement of spectrum intensity. Copyright © 2001 John Wiley & Sons, Ltd.

Porous silicon powder and silica gel particles have been applied as inorganic matrices for the analysis of small molecules in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOFMS). In contrast to conventional MALDI-TOFMS, the signal interference of low-molecular analytes by the matrix has been eliminated. Almost no fragmentations of the analytes were observed. Effects of various factors, such as the particle and pore size, the suspending solution, and sample preparation procedures, on the intensity of mass spectra have been investigated. The pore structure of the inorganic matrix and penetration of the analytes into the pores must be optimized for effective desorption and ionization of the analytes. Matrices (DHB and HCCA) were covalently bound to silica gel for improvement of spectrum intensity. Copyright © 2001 John Wiley & Sons, Ltd.

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In this paper, a practice of design of experiments and data analysis for 28nm technology NMOS devices was introduced. Integrated-Optimum Optimal Design design with I-optimality method criterion was used for 5 input variables with 3 levels for each device, where total 23 runs/wafers were generated. Based on the response surface models by an excellent regression on device parametric data, both automatic maximum desirability analyses by JMP software and engineering knowledge-based analysis was were carried out. The two methods generated similar prediction and the latter one helps gaining more insight on the device optimization. The prediction was exactly reproduced in silicon experiement.

In this work, the formation of nickel germanide is investigated by spectroscopic ellipsometry. The phase transition and thickness of nickel germanide were identified nondestructively by spectroscopic ellipsometry. The results were compared with traditional analytical tools such as four point probe, Rutherford backscattering spectrometry, and X-ray photoelectron spectroscopy, and showed good agreement. The optical properties (refractive index) of nickel germanide were obtained from spectroscopic ellipsometer measurements and applied to the thickness measurement of nickel germanide successfully.