Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and Applications

Dye-sensitized solar cells (DSCs) offer the possibilities to design solar cells with a large flexibility in shape, color, and transparency. DSC research groups have been established around the worl ...

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Dye-Sensitized Solar Cells

The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties * To whom correspondence should be addressed. Phone, 404-8940292; fax, 404-894-0294; e-mail, mostafa.el-sayed@ chemistry.gatech.edu. † Case Western Reserve UniversitysMillis 2258. ‡ Phone, 216-368-5918; fax, 216-368-3006; e-mail, burda@case.edu. § Georgia Institute of Technology. 1025 Chem. Rev. 2005, 105, 1025−1102

Chemistry and properties of nanocrystals of different shapes.

Recent developments have greatly improved the sensitivity of optical sensors based on metal nanoparticle arrays and single nanoparticles. We introduce the localized surface plasmon resonance (LSPR) sensor and describe how its exquisite sensitivity to size, shape and environment can be harnessed to detect molecular binding events and changes in molecular conformation. We then describe recent progress in three areas representing the most significant challenges: pushing sensitivity towards the single-molecule detection limit, combining LSPR with complementary molecular identification techniques such as surface-enhanced Raman spectroscopy, and practical development of sensors and instrumentation for routine use and high-throughput detection. This review highlights several exceptionally promising research directions and discusses how diverse applications of plasmonic nanoparticles can be integrated in the near future.

Biosensing with plasmonic nanosensors

2.3. Evaluation of Photocatalytic Water Splitting 6507 2.3.1. Photocatalytic Activity 6507 2.3.2. Photocatalytic Stability 6507 3. UV-Active Photocatalysts for Water Splitting 6507 3.1. d0 Metal Oxide Photocatalyts 6507 3.1.1. Ti-, Zr-Based Oxides 6507 3.1.2. Nb-, Ta-Based Oxides 6514 3.1.3. W-, Mo-Based Oxides 6517 3.1.4. Other d0 Metal Oxides 6518 3.2. d10 Metal Oxide Photocatalyts 6518 3.3. f0 Metal Oxide Photocatalysts 6518 3.4. Nonoxide Photocatalysts 6518 4. Approaches to Modifying the Electronic Band Structure for Visible-Light Harvesting 6519

Semiconductor-based Photocatalytic Hydrogen Generation

A NaA zeolite membrane was synthesized on the surface of the stainless steel stab. The membrane was characterized by XRD and SEM. The membrane was continuous and highly intergrown. The size of NaA zeolite crystals was about 5 similar to 6 mum.

Preparation of zeolite-metal composite membrane

OBJECTIVE
The emergence of critical values gives a warning to the medical safety of hospitalized patients, especially Cardiosurgery Intensive Care Unit (CSICU) patients. The aim of this study was to investigate the association between early postoperative critical values and the prognosis of patients after cardiac surgery.


METHODS
Clinical data of the patients were obtained from the Cardiac Critical Care Clinical Database of the Cardiovascular Intensive Care Unit of Nanjing First Hospital. A total of 1,598 consecutive patients undergoing cardiac surgery were enrolled in this retrospective cohort study, during the period from July 2019 to December 2020. According to whether critical value occurred within 7 days after cardiac surgery, patients were divided into two groups: the critical value group and control group. COX regression and survival analysis were performed to analyze the clinical data of the two groups. The area under the receiver operating characteristic curve (ROC) was used to assess the critical value's predictive value and determine the optimal cutoff value.


RESULTS
With patients in the critical value group, the 28-day mortality after cardiac surgery was 21.98%, significantly higher than that of the control group (P < 0.05). Logistic regression analysis revealed the APACHE II score (Adjusted HR-1.11, 95% CI-1.043-1.185) and critical value group (Adjusted HR-13.57, 95% CI-6.714-27.435 ) were independent predictors of 28-day mortality after cardiac surgery. The ROC curve showed that the critical value case model (AUC = 0.748 ± 0.052, P < 0.05) could effectively predict the 28-day mortality, and the optimum cutoff was 1 case (sensitivity 52.63%, specificity 95.70%).


CONCLUSIONS
One or more reported cases of critical values in the early postoperative period could be an independent risk factor for 28-day mortality in patients undergoing cardiac surgery. The predictive model based on critical value might be effective in clinical therapy and risk stratification.

Association of Critical Value With 28-Day Mortality After Cardiac Surgery.

By converting the energy of nuclear radiation to excited electrons and holes, semiconductor detectors have provided a highly efficient way for detecting them, such as photons or charged particles. However, for detecting the radiated neutrons, those conventional semiconductors hardly behave well, as few of them possess enough capability for capturing these neutral particles. While the element Gd has the highest nuclear cross section, here for searching proper neutron-detecting semiconductors, we investigate theoretically the Gd chalcogenides whose electronic band structures have never been characterized clearly. Among them, we identify that γ-phase Gd2Se3 should be the best candidate for neutron detecting since it possesses not only the right bandgap of 1.76 eV for devices working under room temperature but also the desired indirect gap nature for charge carriers surviving longer. We propose further that semiconductor neutron detectors with single-neutron sensitivity can be realized with such a Gd-chalcogenide on the condition that their crystals can be grown with good quality.

https://iopscience.iop.org/article/10.1088/0953-8984/28/18/185501/pdf

The electronic band structures of gadolinium chalcogenides: a first-principles prediction for neutron detecting.

Abundant pocket-like defects are engineered on the edge of carbon nitride nanodots (CN1.9), using hydrazine groups to attack carbon atoms which results in CN heterocycle opening of porous graphitic C3N4. These edge defects on CN1.9 not only modulate the electronic structure, extend light absorption, and promote photoexcited electron transfer but also lead to c(HCO3–)/c(CO2, aq)-dependent photocatalytic CO evolution in CO2 bubbling HCO3– aqueous solution (pH ≈ 7.1∼7.5). Even in the N2/HCO3– system (pH ≈ 8.17), wherein c(HCO3–) is about 67 times higher than c(CO2, aq), the CO production also attains 48.6 μmol g–1 h–1 on CN1.9. In the same experimental condition, almost no CO produces except for H2 on graphitic carbon nitride (GCN). DFT theoretical calculation reveals that edge defects prefer to contact with HCO3– and proton to orient a special reaction pathway of HCO3* → H2CO3* → CO on CN1.9 with a relatively low-energy barrier rather than HCO3* → H2O–CO2* → CO on GCN. 

Xiaobo Chen

Papers

Preparation of zeolite-metal composite membrane

Association of Critical Value With 28-Day Mortality After Cardiac Surgery.

The electronic band structures of gadolinium chalcogenides: a first-principles prediction for neutron detecting.

Edge Engineering of Carbon Nitride Nanodots with Pocket-like Sites for Effective Photoreduction of Bicarbonate to CO under Visible Light

Robust semi-supervised data representation and imputation by correntropy based constraint nonnegative matrix factorization