Luminescent Functional Metal–Organic Frameworks

Fluorescent carbon nanoparticles or carbon quantum dots (CQDs) are a new class of carbon nanomaterials that have emerged recently and have garnered much interest as potential competitors to conventional semiconductor quantum dots. In addition to their comparable optical properties, CQDs have the desired advantages of low toxicity, environmental friendliness low cost and simple synthetic routes. Moreover, surface passivation and functionalization of CQDs allow for the control of their physicochemical properties. Since their discovery, CQDs have found many applications in the fields of chemical sensing, biosensing, bioimaging, nanomedicine, photocatalysis and electrocatalysis. This article reviews the progress in the research and development of CQDs with an emphasis on their synthesis, functionalization and technical applications along with some discussion on challenges and perspectives in this exciting and promising field.

Carbon quantum dots and their applications

Recent startling interest for lanthanide luminescence is stimulated by the continuously expanding need for luminescent materials meeting the stringent requirements of telecommunication, lighting, electroluminescent devices, (bio-)analytical sensors and bio-imaging set-ups. This critical review describes the latest developments in (i) the sensitization of near-infrared luminescence, (ii) “soft” luminescent materials (liquid crystals, ionic liquids, ionogels), (iii) electroluminescent materials for organic light emitting diodes, with emphasis on white light generation, and (iv) applications in luminescent bio-sensing and bio-imaging based on time-resolved detection and multiphoton excitation (500 references).

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Lanthanide luminescence for functional materials and bio-sciences

Lanthanide-based luminescent hybrid materials.

There is a special reason for reviewing this book at this time: it is the 50th edition of a compendium that is known and used frequently in most chemical and physical laboratories in many parts of the world. Surely, a publication that has been published for 56 years, withstanding the vagaries of science in this century, must have had something to offer. There is another reason: while the book is a standard fixture in most chemical and physical laboratories, including those in medical centers, it is not as frequently seen in the laboratories of physician's offices (those either in solo or group practice). I believe that the Handbook can be useful in those laboratories. One of the reasons, among others, is that the various basic items of information it offers may be helpful in new tests, either physical or chemical, which are continuously being published. The basic information may relate

Handbook of Chemistry and Physics

Geoprivacy protection is a significant concern when sharing data. To support sustainable land management by leveraging existing agricultural data, research is needed to identify how the polygon nature of static field parcels can be obfuscated to allow data sharing among individuals and organizations. In this study, five adaptive polygon‐based obfuscation methods including PN*Rand, PDonut‐k, PDensity‐k, PAHilb, and PDonut_AHilb methods were developed and applied on the Irish Nutrient Management Planning Online (NMP Online) agricultural dataset. The polygon‐based obfuscation methods introduced in this study were designed with the consideration of properties of spatial polygon objects including the spatial coordinates, shape and size of the polygon, topology, and spatial relationship between adjacent polygons that can be used to identify real‐world objects. These methods were developed to guarantee that there is no false‐identification and non‐unique obfuscation which is important for static polygon objects in terms of accuracy and privacy protection. Qualitative approaches were developed to identify the optimal values of inner and outer radii of donut shape based on k‐anonymity satisfaction and subsequently obtain the optimal value of k‐anonymity. Several evaluation methods were implemented to compare the methods performance. Density‐based methods particularly PDonut‐AHilb provide the best trade‐off between field parcel confidentiality and spatial pattern preservation and should be considered for researchers and practitioners obfuscating polygon data.

Implementation of novel polygon‐based obfuscation methods to improve privacy of agricultural data

We have applied an electron cyclotron resonance technique to deposit diamond thin films on various substrates under remote plasma, low temperature (600°C) and low pressure (60 mTorr) conditions. Diamond films were grown on different substrates (silicon, molybdenum) with varying concentrations of precursor gases (methanol and water). A positive substrate bias (50 to 60 V) was found to be essential for the growth of diamond films onto substrates positioned 16 cm below the ECR plasma. The films were characterized by Raman, X-ray diffraction and scanning electron microscopy for microstructure, phase purity and chemical bonding characteristics. The effect of various processing parameters including gas pressure, gas composition, substrate temperature and bias have also been analyzed.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S1946427400489037

Remote Ecr Plasma Deposition of Diamond Thin Films from Water-Methanol Mixtures

Diamond films were grown on (100) and (110) oriented natural diamond substrates by hot filament assisted chemical vapor deposition (HFCVD) to thicknesses of 7 to 100µm. Raman spectroscopy was used to measure tensile stresses of up to ~2GPa for some of the (110) films. The development of stress was attributed to the incorporation of impurities (Re, Mo, and H). Impurity concentrations were greater at the interface than through the film thickness. Up to ~11% H and 50ppm Re were measured in the films with secondary ion mass spectrometry (SIMS). Homoepitaxial diamond films were further characterized using a seven crystal high resolution x-ray diffraction system. This new characterization tool allowed the separation of the effects of mosaicity from those of variation in lattice parameter.

Characterization of Stress and Mosaicity in Homoepitaxial Diamond Films

Status report on the american society for testing and materials E‐42 committee on surface analysis

The effects of thermally cycling Al-Si-Cu VLSI metallization down to −196 °C have been studied in unpatterned and patterned films with and without surface passivation using wafer curvature and x-ray diffraction techniques. Both passivated and unpassivated unpatterned metallization showed development of compressive stresses in the thin film after cooling to −196 °C and warming to 22 °C. This was attributed to plastic deformation at −196 °C leading to a reversal of stress from tensile to compressive upon warming to room temperature. The relaxation of this compressive stress was characterized at room temperature immediately after warming from −196 °C and after cooling from anneals between 50 °C and 250 °C. The stress in patterned (1 to 2 μm line widths) thin films with passivation remained tensile, and this was attributed to a reduction in grain boundary area and inhibition of grain boundary diffusion. Therefore, the tensile stress was maintained even after thermal cycling several times between −196 °C and 2...

Paul H. Holloway

Papers

Implementation of novel polygon‐based obfuscation methods to improve privacy of agricultural data

Remote Ecr Plasma Deposition of Diamond Thin Films from Water-Methanol Mixtures

Characterization of Stress and Mosaicity in Homoepitaxial Diamond Films

Status report on the american society for testing and materials E‐42 committee on surface analysis

Stress generation in Al-Si-Cu metallization resulting from thermal cycling between −196 °C and 250 °C