Si-SiO/sub 2/-Si/sub 3/N/sub 4/-Si

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Decreased bacteria activity on Si<sub>3</sub>N<sub>4</sub> surfaces compared with PEEK or titanium

Decreased bacteria activity on Si<sub>3</sub>N<sub>4</sub> surfaces compared with PEEK or titanium

Abstract: A significant need exists for orthopedic implants that can intrinsically resist bacterial colonization. In this study, three biomaterials that are used in spinal implants – titanium (Ti), poly- ether-ether-ketone (PEEK), and silicon nitride (Si 3 N 4 ) – were tested to understand their respective susceptibility to bacterial infection with Staphylococcus epidermidis, Staphlococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Enterococcus. Specifically, the surface chemistry, wettability, and nanostructured topography of respective biomaterials, and the effects on bacterial biofilm formation, colonization, and growth were investigated. Ti and PEEK were received with as-machined surfaces; both materials are hydrophobic, with net negative surface charges. Two surface finishes of Si 3 N 4 were examined: as-fired and polished. In contrast to Ti and PEEK, the surface of Si 3 N 4 is hydrophilic, with a net positive charge. A decreased biofilm formation was found, as well as fewer live bacteria on both the as-fired and polished Si 3 N 4 . These differences may reflect differential surface chemistry and surface nanostructure properties between the biomaterials tested. Because protein adsorption on material surfaces affects bacterial adhe- sion, the adsorption of fibronectin, vitronectin, and laminin on Ti, PEEK, and Si 3 N 4 were also examined. Significantly greater amounts of these proteins adhered to Si 3 N 4 than to Ti or PEEK. The findings of this study suggest that surface properties of biomaterials lead to differential adsorption of physiologic proteins, and that this phenomenon could explain the observed in-vitro differences in bacterial affinity for the respective biomaterials. Intrinsic biomaterial properties as they relate to resistance to bacterial colonization may reflect a novel strategy toward design- ing future orthopedic implants.
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Biological responses to core&ndash;shell-structured Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>-NH<sub>2</sub> nanoparticles in rats by a nuclear magnetic resonance-based metabonomic strategy

Biological responses to core&ndash;shell-structured Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>-NH<sub>2</sub> nanoparticles in rats by a nuclear magnetic resonance-based metabonomic strategy

aa, acetoacetate; ab, anabasine; ace, acetate; ach, acetylcholine; aco, aconitate; act, acetone; aD, acetamide; ah, aminohippurate; ala, alanine; all, allantoin; arg, arginine; asn, asparagine; Ben, benzoate; Bet, betaine; Bu, butyrate; ch, choline; ci, citrate; cn, creatinine; cr, creatine; Dg, deoxyguanosine; DMa, dimethylamine; DMg, dimethylglycine; DU, deoxyuridine; ea, ethanolamine; eth, ethanol; For, formate; Fum, fumarate; g, glycerol; ga, guanidinoacetate; glc, glucose; gln, glutamine; glu, glutamate; gly, glycine; gPc, glycerolphosphocholine; hB, hydroxybutyrate; hg, homogentisate; hIB, hydroxyisobutyrate; hip, hippurate; hIV, hydroxyisovalerate; IB, isobutyrate; Ile, isoleucine; IP, isopropanol; IV, isovalerate; Kg, ketoglutarate; KIV, ketoisovalerate; l, lipid; lac, lactate; lDl, low-density lipoprotein; leu, leucine; lys, lysine; Ma, methylamine; Mal, malonate; Mg, methylguanidine; Mh, methylhistidine; m-hPa, meta-hydroxyphenylacetate; m-I, myo-inositol; Met, methionine; MM, methylmalonate; Mol, methanol; Na, nicotinamide; NaD, nicotinamide adenine dinucleotide; Nag, N-acetylglutamate; Nas, N-acetyl glycoprotein signal; N-Mh, N-methylnicotinamide; NP, neopterin; o-hPa, ortho-hydroxyphenylacetate; Pa, picolinate; Pag, phenylacetylglycine; Pan, pantothenate; PaP, adenosine 3′,5′-diphosphate; Pc, phosphocholine; Phe, phenylalanine; p-hPa, para-hydroxyphenylacetate; Prop, propionate; Py, pyruvate; ser, serine; suc, succinate; Tau, taurine; Tgl, trigonelline; Thr, threonine; TMaO, trimethylamine N-oxide; Trp, tryptophan; Tyr, tyrosine; Uc, urocanate; Val, valine; VlDl, very-low-density lipoprotein.
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Polyetherimide-grafted Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub> nanoparticles as theranostic agents for simultaneous VEGF siRNA delivery and magnetic resonance cell imaging

Polyetherimide-grafted Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub> nanoparticles as theranostic agents for simultaneous VEGF siRNA delivery and magnetic resonance cell imaging

PEI. The PEI polymer was coated on the surface of Fe 3 O 4 @ SiO 2 nanoparticles, followed by electrostatic adsorption of VEGF shRNA. The Fe 3 O 4 /SiO 2 /PEI/VEGF shRNA nano- composites exhibited negligible hemolysis against human blood, and very low cytotoxicity against MCF-7 cells. Such vectors could be readily internalized into cells and showed significant downregulation of VEGF expression at both the mRNA and protein level in MCF-7 cells. We also revealed that the Fe 3 O 4 /SiO 2 /PEI/VEGF shRNA nanocomposites were able to be used as an efficient nanoprobe for the MR imaging of cancer cells. Taken together, Fe 3 O 4 /SiO 2 /PEI/ VEGF shRNA nanocomposites simultaneously possess dual functions for gene delivery and cellular imaging. Although the in vivo data should be further investigated, based on the in vitro data and findings, the Fe 3 O 4 /SiO 2 /PEI/VEGF shRNA nanocomposite is still a good candidate as a theranostic agent, and has high potential in future medical applications.
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Characteristics and Catalytic Properties of Ni/Ti Si Composite Oxide Catalysts via CO<sub>2</sub> Hydrogenation

Characteristics and Catalytic Properties of Ni/Ti Si Composite Oxide Catalysts via CO<sub>2</sub> Hydrogenation

attractive XRD peaks of NiO also display the strong intensity at 37.3, 43.3, 62.8 and 75.5 [1] for all Ni catalysts. Moreover, NiO peak resulted in the less appearance of the XRD peak of anatase titania crystalline at 25.3  for NiTiSSP and NiTiMCM. The surface areas of the silica samples were remarkably high as expected. However, after the TiO 2 was introduced into the mesoporous SiO 2 surface, the BET surface area of TiSSP

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Metathesis of Ethylene and Trans 2 Butene over MgO Admixed WO<sub>3</sub>/SiO<sub>2</sub> Catalysts

Metathesis of Ethylene and Trans 2 Butene over MgO Admixed WO<sub>3</sub>/SiO<sub>2</sub> Catalysts

The TGA measurements were carried out on the fresh catalysts after exposed in air at room temperature for 3 days and the results are shown Fig. 4. The weight loss of catalysts was found to be in the order: MgO(CP) 34.3% > MgO(SV) 24.3% > MgO(SG) 21.3%. The first region of weight loss occurred at 40ºC - 250ºC was attributed to the removal of the physisorbed water molecules. The major weight loss at around 250ºC - 450ºC was attributed to the decomposition of magnesium hydroxide to magnesium oxide. The decomposition of Mg(OH) 2 to form MgO was suggested to complete in the temperature region 500ºC
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A first principles study of sub-monolayer Ge on Si(001)

A first principles study of sub-monolayer Ge on Si(001)

is interesting to compare this result with the single missing dimer in Si(001), which has an identical structure, apart from the Ge in the top layer. There, the bonds across the trench have a length of 2.56 ˚ A [29,30]; the similarity suggests that the limiting factor on the relaxation in both cases is the Si-Si distance. The Ge dimers neighbouring the trench show an inward relaxation of 0.65 ˚ A from their positions in the perfect monolayer. The up and down Si–Ge bond lengths neighbouring the trench are 2.58 and 2.45 ˚ A, so that there is a significant lengthening compared with the perfect Ge monolayer. As expected, for smaller values of n, the relaxation around the trench is less pronounced. For example, in the n = 4 case, the SiSi separation across the trench is 2.63 ˚ A, and the inward relaxation of the Ge dimers neighbouring the trench is 0.48 ˚ A. The suppression of relaxation for small spacings is clearly responsible for the strong n-dependence of E f (n), corresponding to the effective repulsion
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Immobilized transferrin Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub> nanoparticle with high doxorubicin loading for dual-targeted tumor drug delivery

Immobilized transferrin Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub> nanoparticle with high doxorubicin loading for dual-targeted tumor drug delivery

The procedures for generation and drug loading of TfDMP are shown in Figure 1. By coupling GA with amino- immobilized Fe 3 O 4 @SiO 2 , the surface of the magnetic nanoparticle can be modified with both carboxyl and protected amino groups. The dual function magnetic nanoparticles produced were used as carriers. As a multi-armed crosslinker, PLGA has large numbers of carboxyl functional groups, as well as an amino end-group. Thus, PLGA can couple with the carboxyl of DMP, in the presence of NHS and EDC, through an amide bond. Thereby, large numbers of carboxyl functional groups can be introduced onto the surface of DMP. It is known that DOX has an amino group, which is not the active site for DOX effectiveness. Thus, DOX can be immobilized (under vacuum) onto the PLGA-coated layer of the DMP, in the presence of NHS and EDC, through amide bonding. Finally, after deprotection of DMP’s amino groups, Tf can be coupled, through amide bonding.
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Toxicity evaluation of Gd<sub>2</sub>O<sub>3</sub>@SiO<sub>2</sub> nanoparticles prepared by laser ablation in liquid as MRI contrast agents in vivo

Toxicity evaluation of Gd<sub>2</sub>O<sub>3</sub>@SiO<sub>2</sub> nanoparticles prepared by laser ablation in liquid as MRI contrast agents in vivo

Abstract: Poor toxicity characterization is one obstacle to the clinical deployment of Gd 2 O 3 @ SiO 2 core-shell nanoparticles (Gd-NPs) for use as magnetic resonance (MR) imaging contrast agents. To date, there is no systematic toxicity data available for Gd-NPs prepared by laser abla- tion in liquid. In this article, we systematically studied the Gd-NPs’ cytotoxicity, apoptosis in vitro, immunotoxicity, blood circulation half-life, biodistribution and excretion in vivo, as well as pharmacodynamics. The results show the toxicity, and in vivo MR data show that these NPs are a good contrast agent for preclinical applications. No significant differences were found in cell viability, apoptosis, and immunotoxicity between our Gd-NPs and Gd in a DTPA (diethyl- enetriaminepentaacetic acid) chelator. Biodistribution data reveal a greater accumulation of the Gd-NPs in the liver, spleen, lung, and tumor than in the kidney, heart, and brain. Approximately 50% of the Gd is excreted via the hepatobiliary system within 4 weeks. Furthermore, dynamic contrast-enhanced T1-weighted MR images of xenografted murine tumors were obtained after intravenous administration of the Gd-NPs. Collectively, the single step preparation of Gd-NPs by laser ablation in liquid produces particles with satisfactory cytotoxicity, minimal immuno- toxicity, and efficient MR contrast. This may lead to their utility as molecular imaging contrast agents in MR imaging for cancer diagnosis.
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Electron trapping in metal-insulator-semiconductor structures on n-GaN with SiO2 and Si3N4 dielectrics

Electron trapping in metal-insulator-semiconductor structures on n-GaN with SiO2 and Si3N4 dielectrics

states occupied under thermal equilibrium ( i.e., V G = 0 ) . Therefore, little further trapping should be possible at the GaN/ nitrided-thin-Ga 2 O 3 interface due to substrate electron injection. The situation is different for Si 3 N 4 samples as in Fig. 1. In this case, V fb = 1 V corresponds to a finite energy interval next to the GaN conduction band edge in which interface states possibly existing in the samples are unoccu- pied under thermal equilibrium.

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Assessing the axonal translocation of CeO<sub>2</sub> and SiO<sub>2</sub> nanoparticles in the sciatic nerve fibers of the frog: an ex vivo electrophysiological study

Assessing the axonal translocation of CeO<sub>2</sub> and SiO<sub>2</sub> nanoparticles in the sciatic nerve fibers of the frog: an ex vivo electrophysiological study

Frogs (Rana ridibunda) of either sex and of the same age (ranging from 12 to 15 months), weighing 40–60 g, were used. The frogs were euthanatized (decapitated and pithed), and the sciatic nerves were dissected from the spinal cord to the knee, immersed in standard physiological saline solution, and cleaned under a dissection microscope. All experimental procedures were conducted in accordance with the protocols outlined by the Aristotle University of Thessaloniki, Greece, regarding the recommended standard practices for Biological Investigations. When required, the epineural sheath was removed. The composition of the saline was (in mmol/L): NaCl 135, KCl 4.7, CaCl 2 2.4, MgCl 2 1.1, NaHCO 3 1.0, HEPES 10, glucose 11 (pH 7.4). The nerve was mounted across a three-chambered record- ing bath, made of Plexiglas, a diagram of which is shown in Figure 1A. The recording bath has been used in a variety of ex vivo neurotoxicological studies and it is fully described elsewhere, 34–36 but a short description will be given below in
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The association of self-injurious behaviour and suicide attempts with recurrent idiopathic pain in adolescents: evidence from a population-based study

The association of self-injurious behaviour and suicide attempts with recurrent idiopathic pain in adolescents: evidence from a population-based study

Background: While several population‑based studies report that pain is independently associated with higher rates of self‑destructive behaviour (suicidal ideation, suicide attempts, and self‑injurious behaviour) in adults, studies in adoles‑ cents are rare and limited to specific chronic pain conditions. The aim of this study was to investigate the link between self‑reported idiopathic pain and the prevalence and frequency of self‑injury (SI) and suicide attempts in adolescents. Methods: Data from a cross‑sectional, school‑based sample was derived to assess SI, suicide attempts, recurrent pain symptoms and various areas of emotional and behavioural problems via a self‑report booklet including the Youth Self‑Report (YSR). Adolescents were assigned to two groups (presence of pain vs. no pain) for analysis. Data from 5,504 students of 116 schools in a region of South Western Germany was available. A series of unadjusted and adjusted multinomial logistic regression models were performed to address the association of pain, SI, and suicide attempts. Results: 929 (16.88%) respondents reported recurrent pain in one of three areas of pain symptoms assessed (gen‑ eral pain, headache, and abdominal pain). Adolescents who reported pain also reported greater psychopathological distress on all sub‑scales of the YSR. The presence of pain was significantly associated with an increased risk ratio (RR) for SI (1–3 incidences in the past year: RR: 2.96; >3 incidences: RR: 6.04) and suicide attempts (one attempt: RR: 3.63; multiple attempts: RR: 5.4) in unadjusted analysis. Similarly, increased RR was observed when adjusting for sociode‑ mographic variables. While controlling for psychopathology attenuated this association, it remained significant (RRs: 1.4–1.8). Sub‑sequent sensitivity analysis revealed different RR by location and frequency of pain symptoms.
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Heterointerface dipoles: Applications to (a) Si-SiO2, (b) nitrided Si-N-SiO2, and (c) SiC-SiO2 interfaces

Heterointerface dipoles: Applications to (a) Si-SiO2, (b) nitrided Si-N-SiO2, and (c) SiC-SiO2 interfaces

Consider next the empirical chemical approach. As noted above, the computational basis for including near-nearest- and more-remote-neighbor chemical induction effects in molecules was first developed by Carver and Gray. 11 This was subsequently extended by Lucovsky and co-workers to network amorphous solids. 14,15 Using the method of Ref. 14, the interface between crystalline Si oriented in a ~ 111 ! direc- tion, and noncrystalline SiO 2 is represented by the molecular cluster in Fig. 2 ~ a ! . The Si side of the cluster consists of a three atomic shells ~ two are shown in the diagram ! : ~ i ! the Si atom at the interface in shell ~ 1 ! , ~ ii ! the three nearest- neighbor Si atoms in shell ~ 2 ! , and ~ iii ! nine pseudoatoms in shell ~ 3 ! , which are characterized by the average electrone- gativity of the rest of the network. A similar construction is used for the SiO 2 network on the other side of the interface. In this case, the cluster contains atomic shells of alternating Si and O atoms, as well as a final shell that is comprised of pseudoatoms with the average electronegativity of the SiO 2 network (S average 5 @ (S Si )(Si O ) 2 # 1/3 5 4.26). A similar cluster
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Effect of Sub Grains and Crystal Defects on Monolike Si Solar Cell Performance

Effect of Sub Grains and Crystal Defects on Monolike Si Solar Cell Performance

formance is simulated by PC1D. Two representative cells from the interior and corner bricks were chosen for mo- deling. There are four distinct cell regions that may be classified which have individual effects on cell perfor- mance. Monolike silicon wafers may have 1) (100) ori- ented, textured single crystalline regions; 2) (100) ori- ented, textured single crystalline regions displaying dis- location patterns; 3) (311) oriented, planar single crystal- line regions; and 4) planar, multicrystalline regions pos- sessing many crystal orientations. Inspection of the rep- resentative interior brick cell reveals the following region ratio: 70% region 1, 15% region 2, and 15% region 3. Similar inspection of the representative corner brick cell reveals the following ratio: 36% region 1, 25%, region 2, 22% region 3, and 17% region 4. IQE and external sur- face reflectance curves were collected for each region of the representative cells and are shown in Figure 5. Qualitative inspection of IQE curves shows that regions 2 and 4 have significant degradation of long wavelength response which may be consistent with low minority carrier bulk lifetime (τ bulk ). Low surface reflectance is
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Effect of Alkaline and Alkaline Earth Metal Oxides Addition on the Glass Formation and Crystallization of ZnO Al<sub>2</sub>O<sub>3</sub> SiO<sub>2</sub> Glasses

Effect of Alkaline and Alkaline Earth Metal Oxides Addition on the Glass Formation and Crystallization of ZnO Al<sub>2</sub>O<sub>3</sub> SiO<sub>2</sub> Glasses

The appearances of as-casted samples are shown in Table 3 and 4. According to Table 3, only 20AZ3Li and 20AZ3Li6T became glasses among samples containing alkaline metal oxides, and the others crystallized and became opaque. 20AZ3Li6T crystallized partially by surface crystallization and its glassy part had light yellow colour which is also shown in other glasses containing TiO 2 . This color is estimated to be caused by

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In vitro and in vivo targeting imaging of pancreatic cancer using a&nbsp;Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>&nbsp;nanoprobe modified with anti-mesothelin antibody

In vitro and in vivo targeting imaging of pancreatic cancer using a&nbsp;Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>&nbsp;nanoprobe modified with anti-mesothelin antibody

The T2 signal values of experimental group xenograft were decreased by 342.533 ± 42.6 after injection of the target probe, and the control group was decreased by − 61.233 ± 33.9 after injection of saline solution, while the FS group decreased by − 58.7 ± 19.4 at 2.5 hours. The decrease of tumor signal by A-MFS was much more significant than that by saline and FS (P,0.05). Results could be seen in Figures S2 and S3. Similarly, the T2-weighted images showed that the tumor signal in the experimental group was decreased after injec- tion of the probe FS modified with anti-MSLN antibody, while the control and FS groups were barely altered. Due to its paramagnetic properties, Fe 3 O 4 acts as a negative contrast agent of MRI. It decreases the T2-weighted tissue signal to enhance the contrast by shortening the transverse relaxation time T2, suggesting that the nanoprobe selectively accumulated in the pancreatic cancer tissue, shortened the transverse relaxation time, and decreased signal of tissue. Therefore, FS modified with anti-MSLN antibody is a good T2 targeting agent in pancreatic cancer of nude mice. It may
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A multilayered approach of Si/SiO to promote carrier transport in electroluminescence of Si nanocrystals

A multilayered approach of Si/SiO to promote carrier transport in electroluminescence of Si nanocrystals

Forty-layered Si/SiO samples were prepared by evapor- ating Si and SiO alternatively by electron-beam and resistance heating, respectively, onto p + -type Si sub- strates (0.5 to approximately 1 Ω ·cm) in a vacuum chamber with a base pressure less than 5 × 10 -5 Pa. An ex-situ furnace annealing in nitrogen atmosphere at 1,100°C was performed for 1 h to induce phase separa- tion (JZ and ML, unpublished data) [3,4,7,11] to form Si-nc. The thickness of SiO remained at 3.75 nm, and that of Si interlayer (d Si ) was variable.

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In vitro toxicity of Fe<sub>m</sub>O<sub>n</sub>, Fe<sub>m</sub>O<sub>n</sub>-SiO<sub>2</sub> composite, and SiO<sub>2</sub>-Fe<sub>m</sub>O<sub>n</sub> core-shell magnetic nanoparticles

In vitro toxicity of Fe<sub>m</sub>O<sub>n</sub>, Fe<sub>m</sub>O<sub>n</sub>-SiO<sub>2</sub> composite, and SiO<sub>2</sub>-Fe<sub>m</sub>O<sub>n</sub> core-shell magnetic nanoparticles

Three different methods of IONP synthesis are shown in schematic form in Figure 1. According to TEM imaging, bare IONPs were rod-shaped with mean sizes of 10.5 ± 2.57 nm in diameter and 42.7 ± 6.82 nm in length (Figure 2A), suggesting that the nucleation process was initiated by γ -Fe 2 O 3 . Using TEM characterization, Fe m O n -SiO 2 composite flake-like and SiO 2 -Fe m O n core-shell IONPs demonstrated spherical shape with mean diameter of 98 ± 22 and 101 ± 19 nm, respectively (Figure 2B–E). Fe m O n -SiO 2 composite IONPs consisted of irregularly ordered nanoflakes of iron oxide and silica (Figure 2B, inset). In TEM images of SiO 2 -Fe m O n core-shell IONPs, silica core was not visible probably because of the interference of electron-dense iron oxide shell (Figure 2C, inset). Atomic force microscopy images show no visible aggregates of Fe m O n -SiO 2 composite IONPs (Figure 2D) and aggregation of SiO 2 -Fe m O n core-shell IONPs (Figure 2E) on a glass substrate. The aggregates of SiO 2 -Fe m O n core-shell IONPs are presumably forming during their drying because of an increase of concentration. Hydrodynamic diameters did not differ between Fe m O n -SiO 2 composite flake-like and SiO 2 - Fe m O n core-shell IONPs and were close to their original size, whereas bare IONPs demonstrated significant aggregation that does not allow estimation of their size using DLS because this method is only applicable for particles ,10 µ m (Figure 2F). Mass magnetization curves of IONPs are shown in Figure 2G. The saturation mass magnetization (M) of Fe m O n -SiO 2 com- posite and SiO 2 -Fe m O n core-shell IONPs was estimated to be 11.0 emu/g, whereas uncoated IONPs were characterized by M = 37.2 emu/g. The lower saturation mass magnetization of SiO 2 -containing IONPs is most likely explained by the pres- ence of nonmagnetic silica inclusions. The lack of hysteresis loop on magnetization curves for all three types of IONPs indicates a superparamagnetic behavior of the nanoparticles.
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Vancomycin-modified Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>@Ag microflowers as effective antimicrobial agents

Vancomycin-modified Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>@Ag microflowers as effective antimicrobial agents

of bacterial colonies in the control and treated groups of different microstructures after 12-h cultivation. The control (absence of particles) and Fe 3 O 4 @SiO 2 microsphere-treated solutions did not inhibit the bacterial growth. The Fe 3 O 4 @ SiO 2 –Ag seed showed higher antibacterial efficiency compared with its precursor Fe 3 O 4 @SiO 2 microspheres. After the decoration of Ag seeds and flower-like Ag pet- als, the number of E. coli and MRSA colonies gradually decreased. These results prove that Ag-coated magnetic microcomposites exhibit antibacterial activities against both Gram-negative and Gram-positive bacterial patho- gens. The bactericidal effect also increased significantly with increasing Ag coating components surrounding the magnetic core. Few colonies of E. coli were found during treatment with the Fe 3 O 4 @SiO 2 @Ag microflowers, whereas bacterial colonies of MRSA were still observed in Ag microflower-treated group. MRSA showed less suscepti- bility to the Fe 3 O 4 @SiO 2 @Ag microflowers than E. coli. The Fe 3 O 4 @SiO 2 @Ag microflowers cannot effectively kill MRSA at 20 μ g mL −1 within 60 min. However, almost no
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Interfacial strain-induced self-organization in semiconductor dielectric gate stacks. I. Strain relief at the Si-SiO2 interface

Interfacial strain-induced self-organization in semiconductor dielectric gate stacks. I. Strain relief at the Si-SiO2 interface

The results of Keister et al., 6 indicated that a monolayer scale SiO layer in as-grown oxides, displays random local bonding arrangements, and is converted to Si-rich and O-rich bonding arrangements after a 900 °C anneal. There is insuf- ficient SXPS or SHG data to determine if the temperature dependence of the extent of completion of this interfacial reaction follows the same trajectory as the bulk reaction. However, the application of bond constraint theory 共 BCT 兲 to these two quantitatively different systems suggests that the underlying driving force for the bulk and interfacial chemical phase separations is indeed the same, and involves a reduc- tion of bond-strain energy.
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Sub-barrier fusion of Si+Si systems

Sub-barrier fusion of Si+Si systems

vides an energy loss signal ∆ E, while the two MCPs yield the time of flights (TOF) together with the silicon detec- tor. In this configuration the silicon detector measures the residual energy of the ER and gives both the trigger for data acquisition and the start signal for the TOF. Typical spectra of TOF as a function of the residual energy E are shown in Fig. 3, where a good separation of ER events from the residual beam can be appreciated at energies both above and below the Coulomb barrier. Analogous two- dimensional spectra of TOF vs. ∆E and ∆E vs. E were used in the data analysis.
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