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Topic Review
Variable Combinations of Tridentate Ligands in Pt(η3-X3L)(PL) Derivatives
There are over fifty examples in which the inner coordination spheres about the Pt(II) atoms of the Pt(η3-X3L)(PL) type are formed by variable combinations of donor atoms of tridentate ligands. Each η3-ligand creates two metallocyclic rings. The complexes based on membered metallocyclic rings can be divided into four groups: 1. 6+6-Membered Metallocyclic Rings, 2. 6+5-Membered Metallocyclic Rings, 3. 5+6-Membered Metallocyclic Rings, and 4. 5+5-Membered Metallocyclic Rings.
  • 218
  • 18 Apr 2023
Topic Review
Valuable Organic Acids
A ruminant-based carboxylate platform based on mixed or undefined anaerobic co-cultures of rumen microorganisms can convert the carbohydrate polymers in the lignocellulosic part of organic waste streams to carboxylic acids that can be upgraded to biofuels or green chemicals.
  • 965
  • 27 Sep 2021
Topic Review
Ti:Sa Crystals
In this paper, Ti:Sa amplifiers with crystals of the different geometries are discussed. Benefits of using this active medium for a thin disk (TD) and slab amplifiers are evaluated numerically and tested experimentally. Thermal management for amplifiers with multi-kW average power and multi-J pulse energy has been demonstrated. The presented numerical simulations revealed the existing limitations for heat extraction in TD geometry in the sub-joule energy regime for higher repetition rate operation. Geometry conversion from TD to thin-slab (TS) and cross-thin-slab (XTS) configurations significantly increases the cooling efficiency with an acceptable crystal temperature for pump average power values up to few kW with room temperature cooling, and up to tens of kW with cryogenic cooling. The abilities to attain 0.3 J output energy and a greater than 50% extraction efficiency were demonstrated with a repetition rate exceeding 10 kHz with room temperature cooling and one order more of a repetition rate with cryogenic conditions with pulsed pumping. Direct diode pumping simulated for CW regimes demonstrated 1.4 kW output power with 34% extraction efficiency using room temperature cooling and more than 10 kW and ~40% efficiency with cryogenic cooling.
  • 405
  • 19 Oct 2021
Topic Review
The Phosphorus Bond
The phosphorus bond in chemical systems, which is an inter- or intramolecular noncovalent interaction, occurs when there is evidence of a net attractive interaction between an electrophilic region associated with a covalently or coordinately bonded phosphorus atom in a molecular entity and a nucleophile in another, or the same, molecular entity. It is the second member of the family of pnictogen bonds, formed by the second member of the pnictogen family of the periodic table. 
  • 1.8K
  • 07 Mar 2022
Topic Review
The Nitrogen Bond
The nitrogen bond in chemical systems occurs when there is evidence of a net attractive interaction between the electrophilic region associated with a covalently or coordinately bound nitrogen atom in a molecular entity and a nucleophile in another, or the same molecular entity. It is the first member of the family of pnictogen bonds formed by the first atom of the pnictogen family, Group 15, of the periodic table, and is an inter- or intra-molecular non-covalent interaction.
  • 1.9K
  • 25 Mar 2022
Topic Review
Structure of Oxide Perovskite
Materials crystalizing in the perovskite crystal structure are common crystals that are currently employed for multiples applications, including transistors, solar cells, light-emitting devices, memories, catalysts, and superconductors.One of the biggest players within the perovskite structures is the family of oxide perovskites. This is a prominent family with the general formula of ABO3, where A commonly designates an alkaline or rare earth metal cation, occupying the 12-fold coordinated cuboctahedral cages of the oxygen sub-lattice, and B stands for a transition-metal cation (e.g., Fe, Ni, Mn, Co, Cu, or Ti) coordinated with six oxygen atoms in an octahedral coordination. In fact, in the perovskite structure, distortions frequently occur due to the deviation from ideal values of ionic size ratios between the different A, B, and O sites of the crystal. In addition, A or B cations may have distinctive sizes and valences that could result into oxygen non-stoichiometry, involving both oxygen excess and/or oxygen deficiency.
  • 3.5K
  • 24 Sep 2021
Topic Review
SDPD Methods to Pharmaceutical Cocrystals and Salts
Modern X-ray diffractometers, powerful computers, and the continuously improving methods of structure determination from powder data, so called SDPD methods, provide a reliable basis for conducting such research in laboratories of any level. 
  • 203
  • 06 Jul 2023
Topic Review
Relevance of Crystal Forms in the Pharmaceutical Field
The existence of multiple crystal forms of an active pharmaceutical ingredients (API) is relevant not only for the selection of the best solid material to carry through the various stages of drug development, including the choice of dosage and of excipients suitable for drug development and marketing, but also in terms of intellectual property protection and/or extension. This is because the physico-chemical properties, such as solubility, dissolution rate, thermal stability, processability, etc., of the solid API may depend, sometimes dramatically, on the crystal form, with important implications on the drug’s ultimate efficacy.
  • 807
  • 26 Aug 2022
Topic Review
Recent Advances in Fabricating Wurtzite AlN
As a representative ultrawide bandgap (UWBG) semiconductor material, wurtzite aluminum nitride (AlN) material has many excellent properties such as high electron mobility (1100 cm2/Vs), high breakdown voltage (11.7 MV/cm), high piezoelectric coefficient, high thermal conductivity (320 W/m·K), high hardness (nine on the Mohs scale), high corrosion resistance, high chemical and thermal stability, as well as high bulk acoustic wave velocity (11,270 m/s).
  • 515
  • 10 Jan 2022
Topic Review
Pt(η3–P1C2X1C2P2)(Y) Derivative Types
Structural data are classified and analyzed for almost seventy complexes of the general formula Pt(η3–P1X1P2)(Y) (X1 = O, N, C, S, Si) and (Y = various monodentate ligands), in which the respective η3–P1X1P2 ligand forms a pair of five-membered metallocyclic rings with a common X1 atom of the P1C2X1C2P2 type.
  • 150
  • 05 Sep 2023
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