847 research outputs found
Tunable Unidirectional Sound Propagation through a Sonic-Crystal-Based Acoustic Diode
Nonreciprocal wave propagation typically requires strong nonlinear materials to break time reversal symmetry. Here, we utilized a
sonic-crystal-based acoustic diode that had broken spatial inversion
symmetry and experimentally realized sound unidirectional transmission
in this acoustic diode. These novel phenomena are attributed to
different mode transitions as well as their associated different energy
conversion efficiencies among different diffraction orders at two sides
of the diode. This nonreciprocal sound transmission could be
systematically controlled by simply mechanically rotating the square
rods of the sonic crystal. Different from nonreciprocity due to the
nonlinear acoustic effect and broken time reversal symmetry, this new
model leads to a one-way effect with higher efficiency, broader
bandwidth, and much less power consumption, showing promising
applications in various sound devices
Synergistic anticancer and antibacterial activities of cordycepin and selected natural bioactive compounds
Peer reviewedPublisher PD
5,5′-Bis(diethylamino)-2,2′-[butane-1,4-diyldioxybis(nitrilomethylidyne)]diphenol
The title complex, C26H38N4O4, was synthesized by the reaction of 4-diethylamino-2-hydroxybenzaldehyde with 1,4-bis(aminooxy)butane in ethanol. It crystallizes as discrete centrosymmetric molecules adopting an extended conformation where the two salicylaldoxime groups are separated from each other. Intramolecular O—H⋯N hydrogen bonding is observed between the hydroxy groups and oxime N atoms. Intermolecular π–π stacking interactions [3.979 (2) Å] between aromatic rings are apparent in the crystal structure. Each ethyl group is disordered over two positions; in one the site occupancy factors are 0.55 and 0.45, in the other 0.53 and 0.47
1,1′-[(Hexane-1,6-diyldioxy)bis(nitrilomethylidyne)]dinaphthalene
The title compound, C28H28N2O2, was synthesized by condensation of 1-naphthaldehyde with 1,6-bis(aminooxy)hexane in ethanol. The molecule is disposed about a crystallographic centre of symmetry. In the crystal structure, molecules are linked through strong intermolecular π–π stacking interactions [interplana distance = 2.986 (2) Å], forming a three-dimensional network
2,2′-{1,1′-[Pentane-1,5-diylbis(oxynitrilo)]diethylidyne}diphenol
In the title compound, C21H26N2O4, there is half a molecule in the asymmetric unit with a crystallographic twofold rotation axis passing through the central C atom of the –CH=N—O—(CH2)5—O—N=CH– bridge. The dihedral angle formed by the two benzene rings is 80.85 (2)°. Strong intramolecular O—H⋯N and C—H⋯O hydrogen bonds help to establish the molecular conformation. There are also weak intermolecular π–π stacking interactions between neighbouring benzene rings [centroid–centroid separation = 3.502 (3) Å]
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Low Cost, Robust, Environmentally Friendly Geopolymer–Mesoporous Carbon Composites for Efficient Solar Powered Steam Generation
High-efficiency, environment friendly, renewable energy-based methods of desalination represent attractive and potentially very powerful solutions to the long-standing problem of global water shortage. Many new laboratory-scale materials have been developed for photothermal desalination but the development of low-cost, easy-to-manufacture, and scalable materials and systems that can convert solar irradiation into exploitable thermal energy in this context is still a significant challenge. This paper presents work on a geopolymer–biomass mesoporous carbon composite (GBMCC) device with mesoporous and macroporous structures for harvesting solar energy, which is then used in a device to generate water vapor with high efficiency using negative pressure, wind-driven, steam generation. The GBMCC device gives water evaporation rates of 1.58 and 2.71 kg m−2 h−1 under 1 and 3 suns illumination, with the solar thermal conversion efficiency up to 84.95% and 67.6%, respectively. A remarkable, record high water vapor generation rate of 7.55 kg m−2 h−1 is achieved under 1 sun solar intensity at the wind speed of 3 m s−1. This is a key step forward todays efficient, sustainable and economical production of clean water from seawater or common wastewater with free solar energy
6,6′-Dihydroxy-2,2′-[(pentane-1,5-diyldioxy)bis(nitrilomethylidyne)]diphenol
The molecule of the title compound, C19H22N2O6, assumes a W-shaped configuration with the dihedral angle between the two halves of the molecule being 82.48 (5)°. There is one half-molecule in the asymmetric unit with a crystallographic twofold rotation axis passing through the central C atom of the five methylene groups in the [—CH=N—O—(CH2)5—O—N=CH—] bridge. The dihedral angle formed by the two benzene rings in each molecule of the title compound is 84.18 (4)°. There are strong intramolecular O—H⋯N and O—H⋯O hydrogen bonds and weak intermolecular π–π stacking interactions between neighbouring benzene rings, and the intermolecular plane-to-plane distances are 3.488 (2) and 3.841 (3) Å along the b and c axes, respectively. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link each molecule to two others, forming an infinite three-dimensional supramolecular structure
2,2′-Dichloro-1,1′-[(propane-1,3-diyldioxy)bis(nitrilomethylidyne)]dibenzene
The title compound, C17H16Cl2N2O2, assumes a V-shape configuration with a dihedral angle between the two halves of the molecule of 79.60 (4)°. The asymmetric unit comprises one half-molecule with a crystallographic twofold rotation axis passing through the central C atom. There are weak intermolecular π–π stacking interactions between neighbouring benzene rings with intermolecular plane-to-plane distances of 3.277 (6) and 3.465 (5) Å along the a and c axes, respectively. In the crystal structure, weak intermolecular C—H⋯O bonds link each molecule to four others to form an infinite three-dimensional network
Thymosin alpha 1 in the prevention of infected pancreatic necrosis following acute necrotising pancreatitis (TRACE trial): protocol of a multicentre, randomised, double-blind, placebo-controlled, parallel-group trial
Introduction
Infected pancreatic necrosis (IPN) and its related septic complications are the major causes of death in patients with acute necrotising pancreatitis (ANP). Therefore, the prevention of IPN is of great clinical value, and immunomodulatory therapy with thymosin alpha 1 may be beneficial. This study was designed to test the hypothesis that the administration of thymosin alpha 1 during the acute phase of ANP will result in a reduced incidence of IPN.
Methods and analysis
This is a randomised, multicentre, double-blind, placebo-controlled study. 520 eligible patients with ANP will be randomised in a 1:1 ratio to receive either the thymosin alpha 1 or the placebo using the same mode of administration. The primary endpoint is the incidence of IPN during the index admission. Most of the secondary endpoints will be registered within the index admission including in-hospital mortality, the incidence of new-onset organ failure and new-onset persistent organ failure (respiration, cardiovascular and renal), receipt of new organ support therapy, requirement for drainage or necrosectomy, bleeding requiring intervention, human leucocyte antigens-DR(HLA-DR) on day 0, day 7, day 14, and so on and adverse events. Considering the possibility of readmission, an additional follow-up will be arranged 90 days after enrolment, and IPN and death at day 90 will also be served as secondary outcomes.
Ethics and dissemination
This study was approved by the ethics committee of Jinling Hospital, Nanjing University (Number 2015NZKY-004-02). The thymosin alpha 1 in the prevention of infected pancreatic necrosis following acute necrotising pancreatitis(TRACE) trial was designed to test the effect of a new therapy focusing on the immune system in preventing secondary infection following ANP. The results of this trial will be disseminated in peer-reviewed journals and at scientific conferences.
Trial registration number ClinicalTrials.gov Registry (NCT02473406)
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