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Apparatus for automatically maintaining a predetermined ratio between the mass of fuel and the mass of air admitted to the cylinder of an internal‐combustion engine, comprising a temperature‐responsive device exposed to the air delivered to the cylinder, a pressure‐responsive device exposed to the pressure of the air admitted to the cylinder, a pressure‐responsive device exposed to the difference between the atmospheric pressure and the boost‐pressure and so arranged as to have an effect in relation to the degree of control exerted by the responsive device exposed to the boost‐pressure alone, which is equal to the ratio between the unswept and swept volumes of the cylinder, means for adjusting the fuel‐to‐air ratio and an operative connexion between said temperature‐responsive device, said pressure‐responsive devices and said adjusting means.

A novel grafted temperature-responsive ReO₄⁻ Imprinted composite membranes (Re-ICMs) was successfully prepared by using polyvinylidene fluoride (PVDF) resin membranes as substrates, this study aimed to separate and purify ReO effectively.

Re-ICMs were synthesized by PVDF resin membranes as the substrate, acrylic acid (AA), acrylamide (AM), ethylene glycol dimethacrylate (EGDMA) were functional monomers. The morphology and structure of Re-ICMs were characterized by scanning electron microscope and Fourier transform infrared spectroscopy.

The maximum adsorption capacity toward ReO₄⁻ was 0.1,163 mmol/g and the separation decree had relation to MnO₄⁻ was 19.3. The optimal operation conditions were studied detailedly and the results as follows: the molar ratios of AA, AM, EGDMA, ascorbic acid, NH4ReO₄, were 0.8, 0.96, 0.02, 0.003 and 0.006. The optimal time and temperature were 20 h and 40°C, respectively. The Langmuir and pseudo-second-order models were fit these adsorption characteristics well.

Rhenium (Re) is mainly used to chemical petroleum and make superalloys for jet engine parts. This study was representing a technology in separate and purify of Re, which provided a method for the development of the petroleum and aviation industry.

This contribution provided a novel method to separate ReO₄⁻ from MnO₄⁻. The maximum adsorption capacity was 0.1163 mmol/g at 35°C and the adsorption equilibrium time was within 2 h. Meanwhile, the adsorption selectivity rate ReO₄⁻/MnO₄⁻ was 19.3 and the desorption rate was 78.3%. Controlling the adsorption experiment at 35°C and desorption experiment at 25°C in aqueous solution, it could remain 61.3% of the initial adsorption capacity with the adsorption selectivity rate of 13.3 by 10 adsorption/desorption cycles, a slight decrease, varied from 78.3% to 65.3%, in desorption rate was observed.

The purpose of this paper is to present synthesis protocol of hydrogel composed of Chitosan (CS) and Poly(ethylene glycol) (PEG) and establish an understanding of its thermal responsive behavior. It aims to prove the basic temperature sensing ability of a novel CS-PEG-based hydrogel and define its sensing span.

This study includes synthesis of CS and PEG-based hydrogel samples by first performing dissolution of both constituents, respectively, and then adding Glutaraldehyde as the cross-linking agent. It further includes proposed hydrogel’s swelling studies and dynamic behavior testing, followed by hydrogel characterization by Fourier transform infrared spectroscopy, X-ray diffraction and SEM. The last section focuses on the use of proposed hydrogel as a temperature sensor.

Detailed experimental results show that a hydrogel comprising of CS and PEG presents a thermally responsive behavior. It offers potential to be used as a temperature responsive hydrogel-based sensor which could be used in medical applications.

This research study presents scope for future research in the field of thermally responsive bio-sensors. It provides basis for the fabrication of a thermal responsive sensor system based on hydrogels that can be used in specific medical applications.

J. Lucas, Ltd. and R. J. Ifield. Dec. 27, 1945, No. 34,919. The flow of liquid fuel from a variable delivery pump to the nozzle in a combustion chamber of a prime mover is controlled by passing the fuel through a valve and a variable orifice, regulating the pump delivery by the pressure drop set up across the orifice and varying the orifice in response to air blower pressure, and controlling the valve by manually adjustable and temperature‐responsive means.

In this study, fabrication of polymer and cotton fabric exhibiting stimuli-responsive wetting and water vapor permeability features together with antibacterial activity was aimed.

Temperature and pH-responsive poly(N-isopropyl acrylamide-graft-chitosan) (PNIPAM-g-CS) copolymer were produced via the free radical addition polymerization method and fixed to the cotton fabric using butane tetracarboxylic acid (BTCA) cross-linker by double-bath impregnation method. The chemical structure of the graft copolymer was characterized by Fourier-transform infrared spectroscopy (FT-IR) spectroscopy and H-Nuclear magnetic resonance (1H NMR) analyses. Thermo-responsive behavior of the fabric was investigated by wetting time and water uptake tests, contact angle measurement and surface energy calculation. Additionally, antibacterial activity of the fabric treated with copolymer was studied against S. aureus bacterium.

PNIPAM-g-CS graft copolymer was synthesized successfully, which had lower critical solution temperature (LCST) value of 32 °C and exhibited thermo-responsive property. The treated fabrics exhibited hydrophilic character at temperatures below the LCST and hydrophobic character at temperatures above the LCST. It was found that polymer-coated fabric could have regulated the water vapor permeability by the change in its pore size and hydrophilicity depending on the temperature. Additionally, treated fabric displayed a pH-responsive water absorption behavior and strong antibacterial activity against S.aureus bacterium.

In the study, it has been shown that the cotton fabrics can be fabricated which have antibacterial activity and capable of pH and temperature responsive smart moisture/water management by application of copolymer. It is thought that the fabric structures developed in the study will be promising in the production of medical textile structures where antibacterial activity and thermophysiological comfort are important.

This study aims to prepare an imprinted composite membrane with grafted temperature-sensitive blocks for the efficient adsorption and separation of rhenium(Re) from aqueous solutions.

PVDF resin membrane was used as the substrate, dopamine and chitosan (CS) were used to modify the membrane surface and temperature-sensitive block PDEA was grafted on the membrane surface. Then acrylic acid (AA) and N-methylol acrylamide (N-MAM) were used as the functional monomers, ethyleneglycol dimethacrylate (EGDMA) as the cross-linker and ascorbic acid-hydrogen peroxide (Vc-H₂O₂) as the initiator to obtain the temperature-sensitive ReO4⁻ imprinted composite membranes.

The effect of the preparation process on the performance of CS–Re–TIICM was investigated in detail, and the optimal preparation conditions were as follows: the molar ratios of AA–NH₄ReO₄, N-MAM and EGDMA were 0.13, 0.60 and 1.00, respectively. The optimal temperature and time of the reaction were 40 °C and 24 h. The maximum adsorption capacity of CS–Re–TIICM prepared under optimal conditions was 0.1071 mmol/g, and the separation was 3.90 when MnO4⁻ was used as the interfering ion. The quasi first-order kinetics model and Langmuir model were more suitable to describe the adsorption process.

With the increasing demand for Re, the recovery of Re from Re-containing secondary resources becomes important. This study demonstrated a new material that could be separated and recovered Re in a complex environment, which could effectively alleviate the conflict between the supply and demand of Re.

This contribution provided a new material for the selective separation and purification of ReO4⁻, and the adsorption capacity and separation of CS–Re–TIICM were increased with 1.673 times and 1.219 time compared with other Re adsorbents, respectively. In addition, when it was used for the purification of NH₄ReO₄ crude, the purity was increased from 91.950% to 99.999%.

The purpose of this paper is to prepare a dual-encapsulated halloysite nano-container to release the capsuled inhibitor as an additive for corrosion protection of epoxy coating.

Halloysite nano-containers (HNT) were prepared by simultaneously implanting inhibitor benzotriazole (BTA) into the inside and outside of the halloysite using reduced pressure and layer-by-layer (LBL) assembly, respectively. The microstructure and morphology of treated HNT were investigated using Fourier transform infrared spectroscopy and transmission electron microscopy. In addition, the anti-corrosion behaviors of the composite polyepoxy coating with inhibitor-loaded nano-containers BTA@HNT-2 were investigated using the electrochemical impedance spectroscopy and neutral salt spray test.

Test results showed that the LBL assembly structure of the halloysite nano-container makes the BTA@HNT-2 nano-container be controlled and sustained to release BTA, relying on the pH. Very importantly, the obtained nano-container is also responsive to temperature, owing to the thermosensitivity polyelectrolyte out-shell of the HNT. The result showed R_ct of the composite polyepoxy coating can be sufficient to maintain higher than 8.510E+7 Ω·cm² over 72 h of immersion test. Moreover, the artificial induced defects on the coating surface were sufficiently inhibited in the presence of BTA@HNT-2 nano-container in the polyepoxy coating.

Use of the BTA@HNT-2 as corrosion inhibitor nano-container, with good anti-corrosion property and dual-responsive to pH and temperature, offers a significant rout to prepare smart anti-corrosion coating for protecting metal substrate.

This paper aims to provide an introduction to smart materials, with an emphasis on their capabilities and applications.

Following an introduction, this paper first considers what smart materials are and what they can do. It then discusses existing and emerging applications of shape changing, self-actuating, self-healing, self-diagnostic and self-sensing materials.

Although difficult to define unambiguously, smart materials offer a range of unique characteristics and have been used in a multitude of products, ranging from household goods and novelty items to automotive components and medical devices. They are the topic of extensive research and all manner of new applications will emerge in the future, reflecting both technological developments and a growing awareness of their capabilities.

This paper provides an insight into the rapidly developing technology and applications of smart materials.

In an aircraft undercarriage suspension, a cross member having spaced bearings for mounting said cross member on an aircraft and a bearing part between said spaced bearings; a resilient telescopic unit having a part mounted in said bearing part for sliding movement relative to said cross member; and tie members pivotally connected respectively to said unit and to said cross member at points spaced from said bearing part, whereby the undercarriage vertical load is transmitted from said unit to said cross member wholly through said tic members.

An undercarriage bogie 29 with tandem landing wheels 7,8 is biassed into a tail‐down attitude so that on touching down the rear wheels 8 make contact with the ground before the front wheels 7, thus reducing the initial drag on the undercarriage. As shown in FIG. 1 the bogie is biassed by the shock‐absorber 32, 33 in the leg 1, its lower end being connected ot a pivot 36 on the bogie by a link 34. In an alternative arrangement the undercarriage leg is freely telescopic, an external shock‐absorber being mounted between the leg and bogie.