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1.
Small ; 17(34): e2102635, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34272924

ABSTRACT

The "zero-strain" Li4 Ti5 O12 is an attractive anode material for 3D solid-state thin-film batteries (TFB) to power upcoming autonomous sensor systems. Herein, Li4 Ti5 O12 thin films fabricated by atomic layer deposition (ALD) are electrochemically evaluated for the first time. The developed ALD process with a growth per cycle of 0.6 Å cycle-1 at 300 °C enables high-quality and dense spinel films with superior adhesion after annealing. The short lithium-ion diffusion pathways of the nanostructured 30 nm films result in excellent electrochemical properties. Planar films reveal 98% of the theoretical capacity with 588 mAh cm-3 at 1 C. Substrate-dependent film texture is identified as a key tuning parameter for exceptional C-rate performance. The highly parallel grains of a strong out-of-plane (111)-texture allow capacities of 278 mAh cm-3 at extreme rates of 200 C. Outstanding cycle performance is demonstrated, resulting in 97.9% capacity retention of the initial 366 mAh cm-3 after 1000 cycles at 100 C. Compared to other deposition techniques, the superior performance of ALD Li4 Ti5 O12 is a breakthrough towards scalable high-power 3D TFBs.

2.
ACS Appl Mater Interfaces ; 12(35): 39252-39260, 2020 Sep 02.
Article in English | MEDLINE | ID: mdl-32805107

ABSTRACT

An in-depth understanding of lithium (Li) diffusion barriers is a crucial factor for enabling Li-ion-based devices such as three-dimensional (3D) thin-film batteries and synaptic redox transistors integrated on silicon substrates. Diffusion of Li ions into silicon can damage the surrounding components, detach the device itself, lead to battery capacity loss, and cause an uncontrolled change of the transistor channel conductance. In this study, we analyze for the first time ultrathin 10 nm titanium nitride (TiN) films as a bifunctional Li-ion diffusion barrier and current collector. Thermal atomic layer deposition (ALD) and pulsed chemical vapor deposition (pCVD) are employed for manufacturing ultrathin films. The 10 nm ALD films demonstrate excellent blocking capability with an insertion of only 0.03 Li per TiN formula unit exceeding 200 galvanostatic cycles at 3 µA/cm2 between 0.05 and 3 V versus Li/Li+. An ultralow electrical resistivity of 115 µΩ cm is obtained. In contrast, a partial barrier breakdown is observed for 10 nm pCVD films. High surface quality with low contamination is identified as a key factor for the excellent performance of ALD TiN. Conformal deposition of 10 nm ALD TiN in 3D structures with high aspect ratios of up to 20:1 is demonstrated. The measured capacities of the surface area-enhanced samples are in good agreement with the expected values. High-temperature blocking capability is proven for a typical electrode crystallization step. Ultrathin ALD TiN is an ideal candidate for an electrically conducting Li-ion diffusion barrier for Si-integrated devices.

3.
Nanomaterials (Basel) ; 9(7)2019 Jul 19.
Article in English | MEDLINE | ID: mdl-31331020

ABSTRACT

For the analysis of thin films, with high aspect ratio (HAR) structures, time-of-flight secondary ion mass spectrometry (ToF-SIMS) overcomes several challenges in comparison to other frequently used techniques such as electron microscopy. The research presented herein focuses on two different kinds of HAR structures that represent different semiconductor technologies. In the first study, ToF-SIMS is used to illustrate cobalt seed layer corrosion by the copper electrolyte within the large through-silicon-vias (TSVs) before and after copper electroplating. However, due to the sample's surface topography, ToF-SIMS analysis proved to be difficult due to the geometrical shadowing effects. Henceforth, in the second study, we introduce a new test platform to eliminate the difficulties with the HAR structures, and again, use ToF-SIMS for elemental analysis. We use data image slicing of 3D ToF-SIMS analysis combined with lateral HAR test chips (PillarHall™) to study the uniformity of silicon dopant concentration in atomic layer deposited (ALD) HfO2 thin films.

4.
Basic Clin Neurosci ; 10(6): 641-650, 2019.
Article in English | MEDLINE | ID: mdl-32477481

ABSTRACT

INTRODUCTION: Today, addiction to opioids is a serious problem all over the world. Unfortunately, the consumption of these drugs and the number of addicted people have drastically increased. This research aimed at comparing the efficacy of anodal, cathodal, and sham transcranial Direct Current Stimulation (tDCS) on the Brain-Derived Neurotrophic Factor (BDNF) and psychological symptoms in opioid-addicted patients. METHODS: Thirty opioid-addicted patients were selected based on the Diagnostic and Statistical Manual of Mental Disorders, the Fifth Edition, through the convenience sampling method. They were then randomly assigned to 3 groups (10 in each group). The subjects were evaluated before and after tDCS by their serum level of BDNF, desires for drug questionnaire, and depression anxiety stress scale. The data were analyzed by the Kolmogorov-Smirnov test, one-way analysis of variance, as well as the Bonferroni test. RESULTS: Stimulating the Dorsolateral Prefrontal Cortex (DLPFC) led to a significant change in increasing the level of BDNF (P=0.031) and reducing the degree of depression (P=0.018), anxiety (P=0.001), stress (P=0.012), and decreased the level of craving (P=0.001) in opioid-addicted patients. There was no significant difference between active stimulation groups (anodal left/cathodal right and anodal right/cathodal left). The stimulation of the right DLPFC (group B) significantly increased BDNF in comparison with the sham group (sham tDCS) and decreased anxiety and craving. Nonetheless, no change was observed in depression and stress. The stimulation of the left DLPFC (group A) significantly reduced depression, anxiety, stress, and craving compared with the sham group, while there was no change in BDNF. CONCLUSION: In addition to the conventional treatments of opioid-addicted patients, tDCS is an effective complementary treatment.

5.
J Food Sci ; 81(10): C2390-C2397, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27626761

ABSTRACT

A rapid tool for evaluating authenticity was developed and applied to the screening of extra virgin olive oil (EVOO) retail products by using Fourier-transform near infrared (FT-NIR) spectroscopy in combination with univariate and multivariate data analysis methods. Using disposable glass tubes, spectra for 62 reference EVOO, 10 edible oil adulterants, 20 blends consisting of EVOO spiked with adulterants, 88 retail EVOO products and other test samples were rapidly measured in the transmission mode without any sample preparation. The univariate conformity index (CI) and the multivariate supervised soft independent modeling of class analogy (SIMCA) classification tool were used to analyze the various olive oil products which were tested for authenticity against a library of reference EVOO. Better discrimination between the authentic EVOO and some commercial EVOO products was observed with SIMCA than with CI analysis. Approximately 61% of all EVOO commercial products were flagged by SIMCA analysis, suggesting that further analysis be performed to identify quality issues and/or potential adulterants. Due to its simplicity and speed, FT-NIR spectroscopy in combination with multivariate data analysis can be used as a complementary tool to conventional official methods of analysis to rapidly flag EVOO products that may not belong to the class of authentic EVOO.


Subject(s)
Food Contamination/analysis , Olive Oil/chemistry , Spectroscopy, Near-Infrared/methods , Commerce , Food Labeling , Humans , Multivariate Analysis , Olea/chemistry , Olive Oil/standards
6.
J Clin Diagn Res ; 8(10): PD06-9, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25478422

ABSTRACT

Ellis van Creveld syndrome (EVCS) is mainly characterized by dysplatic changes in skeletal structures along with variable inter- and intra-familial patterns. Shortening of bony structures such as ribs and limbs, postaxial polydactyly, and dysplastic teeth and nails are among the clinical presentation of this autosomal recessive disease.

7.
J Gastric Cancer ; 13(2): 106-10, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23844325

ABSTRACT

PURPOSE: We designed our study to evaluate the hypothesis that gastric cancer is correlated with iodine deficiency or thyroid dysfunction. MATERIALS AND METHODS: We investigated the total body iodine reserve, thyroid function status and autoimmune disorder in 40 recently diagnosed gastric adenocarcinoma cases versus 80 healthy controls. The participants came from a region with high gastric cancer rate but sufficient iodine supply due to salt iodination. The investigation included urine iodine level, thyroid gland clinical and ultrasonographic examination, and thyroid function tests. RESULTS: Goiter was detected more frequently in the case group (P=0.001); such a finding, however, was not true for lower than normal urine iodine levels. The free T3 mean level was significantly lower in the case group compared to the control group (P=0.005). CONCLUSIONS: The higher prevalence of goiter rather than low levels of urinary iodine in gastric adenocarcinoma cases suggests that goiter, perhaps due to protracted but currently adjusted iodine deficiency, is more likely to be associated with gastric adenocarcinoma compared to the existing iodine deficiency itself.

8.
J Chromatogr A ; 1218(3): 545-54, 2011 Jan 21.
Article in English | MEDLINE | ID: mdl-21176911

ABSTRACT

The ionic liquid SLB-IL111 column, available from Supelco Inc., is a novel fused capillary gas chromatography (GC) column capable of providing enhanced separations of fatty acid methyl esters (FAMEs) compared to the highly polar cyanopropyl siloxane columns currently recommended for the separation of cis- and trans isomers of fatty acids (FAs), and marketed as SP-2560 and CP-Sil 88. The SLB-IL111 column was operated isothermal at 168°C, with hydrogen as carrier gas at 1.0 mL/min, and the elution profile was characterized using authentic GC standards and synthetic mono-unsaturated fatty acids (MUFAs) and conjugated linoleic acid (CLA) isomers as test mixtures. The SLB-IL111 column provided an improved separation of cis- and trans-18:1 and cis/trans CLA isomers. This is the first direct GC separation of c9,t11- from t7,c9-CLA, and t15-18:1 from c9-18:1, both of which previously required complimentary techniques for their analysis using cyanopropyl siloxane columns. The SLB-IL111 column also provided partial resolution of t13/t14-18:1, c8- from c6/c7-18:1, and for several t,t-CLA isomer pairs. This column also provided elution profiles of the geometric and positional isomers of the 16:1, 20:1 and 18:3 FAMEs that were complementary to those obtained using the cyanopropyl siloxane columns. However, on the SLB-IL111 column the saturated FAs eluted between the cis- and trans MUFAs unlike cyanopropyl siloxane columns that gave a clear separation of most saturated FAs. These differences in elution pattern can be exploited to obtain a more complete analysis of complex lipid mixtures present in ruminant fats.


Subject(s)
Chromatography, Gas/methods , Fatty Acids, Monounsaturated/isolation & purification , Ionic Liquids/chemistry , Linoleic Acids, Conjugated/isolation & purification
9.
J AOAC Int ; 92(5): 1310-26, 2009.
Article in English | MEDLINE | ID: mdl-19916368

ABSTRACT

In recent years, several countries have implemented new regulations regarding the limitation or labeling of the trans fatty acid (TFA) content of foods and dietary supplements. GC methods for fatty acid (FA) analysis have been updated by improving the separation of TFAs from other FAs, especially trans- and cis-18:1, and by focusing more attention on the FAs contained in fats and oils in lower amounts. FA analysis is affected by the limited availability of reference materials. Identifications are frequently made simply by comparison with separations reported in the literature. This report describes the preparation of mixtures containing fatty acid methyl esters (FAMEs) that are not available as reference materials. These mixtures can be used for FAME identifications. The prepared mixtures are analyzed under the experimental conditions of the American Oil Chemists' Society (AOCS) Official Method Ce 1h-05 and AOCS Recommended Practice Ce 1j-07.


Subject(s)
Chromatography, Gas/methods , Fatty Acids/analysis , Fatty Acids/chemistry , Trans Fatty Acids/analysis , Chromatography, High Pressure Liquid , Chromatography, Thin Layer/methods , Dietary Fats/analysis , Esters/chemistry , Fatty Acids/isolation & purification , Hydrazines/chemistry , Iodine/chemistry , Ions , Plant Oils/chemistry , Silver/chemistry , Stereoisomerism , Sulfinic Acids/chemistry , Toluene/chemistry , Trans Fatty Acids/chemistry
10.
J Chromatogr A ; 1214(1-2): 30-6, 2008 Dec 19.
Article in English | MEDLINE | ID: mdl-19004449

ABSTRACT

In recent years, several countries have implemented new regulations regarding limitations or labeling of the trans fatty acid (tFA) content in foods. In order to comply with the new requirements, gas chromatographic methods for fatty acid (FA) analysis have been refined toward the quantitation of a larger number of FAs. Increased attention is also being paid to those present in lower quantities. This article describes a simple procedure for obtaining, pure or in mixtures, geometric and positional isomers of a commercially available monounsaturated FA. cis 10-17:1 Fatty acid methyl ester (FAME) was isomerized into its positional/geometrical isomers by repeated hydrobromination/dehydrobromination of its double bond. Reaction products were fractionated into cis and trans geometric isomers by silver ion HPLC. Pure cis-17:1 FAME positional isomers were obtained by reversed-phase HPLC fractionation and identified by gas chromatography--covalent adduct chemical ionization MS/MS using acetonitrile as the reacting gas. The isomerization with p-toluenesulfinic acid of the purified FAME yielded the corresponding trans isomers; these products were analyzed by GC with flame ionization detection using a Supelco 2560 capillary column in order to determine their elution order and retention times (t(R)). A novel procedure was developed to determine t(r) for 17:1 FAME positional/geometrical isomers relative to that of the commercially available cis 10-17:1 FAME.


Subject(s)
Chromatography, High Pressure Liquid/methods , Fatty Acids/analysis , Fatty Acids/isolation & purification , Gas Chromatography-Mass Spectrometry/methods , Tandem Mass Spectrometry/methods , Fatty Acids/chemistry , Hydrobromic Acid/chemistry , Methylation , Silver/chemistry , Stereoisomerism , Toluene/analogs & derivatives , Toluene/chemistry
11.
Int J Infect Dis ; 11(2): 152-6, 2007 Mar.
Article in English | MEDLINE | ID: mdl-16798042

ABSTRACT

BACKGROUND: Combination drug therapy of brucellosis leads to recovery of symptoms, shortening of symptomatic interval, and decrease in morbidity rate, but single drug therapy is associated with more relapse episodes and a higher rate of drug resistance. Different drug combinations have been evaluated in the treatment of brucellosis. Considering the failure of treatment and relatively high rate of relapse of the disease with the World Health Organization's (WHO) recommended therapeutic regimen, we evaluated a new regimen that we assumed would increase the success of treatment and decrease the rate of relapse. In this study we compare the standard regimen of the WHO, doxycycline-rifampin (DR), to triple therapy with doxycycline-rifampin-amikacin (ADR). METHODS: Two hundred and twenty-eight consecutive patients with brucellosis, who attended Hamedan Sina Hospital between 1999 and 2001, whether seen as outpatients or as inpatients, were enrolled in the study. The participants were randomly allocated to the DR group (receiving doxycycline 100 mg twice a day and rifampin 10 mg/kg body weight/day every morning, both taken orally for eight weeks) or the ADR group (receiving doxycycline 100 mg twice a day and rifampin 10 mg/kg body weight/day every morning, both taken orally for eight weeks, plus 7.5 mg/kg amikacin intramuscularly twice a day for seven days). The patients were checked for the relief of symptoms, drug side-effects, and relapse of disease during the treatment and follow-up. RESULTS: Of the 228 patients enrolled, eight were withdrawn - four patients from the DR group and four from the ADR group. Of the remaining 220 participants (110 in the ADR group and 110 in the DR group), 107 were male (48.6%) and 113 were female (51.4%). Mean age was 35.7+/-17 years in the ADR group and 37+/-18.4 years in the DR group (p=0.5). In the DR group, 97 (88.2%) and in the ADR group, 106 (96.4%) of the patients had relief of symptoms (a significant difference by Chi-square test (p=0.04)). After completion of treatment, and at the sixth month follow-up, nine (9.3%) patients in the DR group and six (5.7%) in the ADR group experienced a relapse of the disease, with no significant difference (p=0.4). Mild side-effects were found in only 10 patients, and none required discontinuation of the therapeutic regimen. Of these patients, four were from DR group and six from ADR group; no significant difference was observed (p=0.7). CONCLUSIONS: Given the fact that the ADR regimen had a higher efficacy and more rapid action in terms of relief of symptoms compared to the DR regimen, and that no significant difference in drug side-effects and disease relapse existed in the patients of either group, adding amikacin to the DR standard treatment regimen seems beneficial.


Subject(s)
Amikacin/therapeutic use , Anti-Bacterial Agents/therapeutic use , Brucellosis/drug therapy , Doxycycline/therapeutic use , Rifampin/therapeutic use , Adolescent , Adult , Amikacin/administration & dosage , Amikacin/adverse effects , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/adverse effects , Doxycycline/administration & dosage , Doxycycline/adverse effects , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Rifampin/administration & dosage , Rifampin/adverse effects
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