[en] In this paper, compact high temperature superconducting (HTS) multiplexers are presented for satellite communication applications. The first multiplexer consists of an input coupling node and three high-order bandpass filters, which is named triplexer. The node is realized by a loop microstrip line instead of conventional T-junction to eliminate the redundant susceptance due to combination of three filters. There are two eight-pole band-pass filters and one ten-pole band-pass filter with cascaded quadruplet structure for realizing high isolation. Moreover, the triplexer is extended to a multiplexer with six channels so as to verify the expansibility of the suggested approach. The triplexer is fabricated using double-sided YBa_2Cu_3O_7 thin films on a 38 × 25 mm"2 LaAlO_3 substrate. The experimental results, when compared with those ones from the T-junction multiplexer, show that our multiplexer has lower insertion loss, smaller sizes and higher isolation between any two channels. Also, good agreement has been achieved between simulations and measurements, which illustrate the effectiveness of our methods for the design of high performance HTS multiplexers. (paper)

[en] The excellent mechanical properties of Graphdiyne (GDY) family has enabled it as an appealing candidate in the field of impact protection. In this in silico study, Monolayer GDY nanosheets of different morphology including GDY, GY-3, GY-4, GY-5 and GY-6 are assessed under hypervelocity impacts (from 1 to 6 km s⁻¹). Tracking the deformation mechanisms under impacts as well as the Probability density function based on atomic Von Mises stress distribution, the length of acetylenic chain clearly alters ductile behavior as well as the energy dissipation/delocalization rate of GDY family during the impact. Results also suggest the penetration energy is not only determined by the energy delocalization rate but also sensitive to impact velocity for nanosheet with various acetylenic chain length. GY-5 with a much lower energy delocalization rate presents a close penetration energy comparing with GDY at a low impact at ∼2.0 km s⁻¹, its superior ductility granted by long acetylenic chain not only dissipates kinetic energy of projectile via deformation, but also extends time for acceleration during the contact with projectile. Considering the impact resist performance of GDY family in terms of Specific penetration energy, GY-5 with the perfect balance between material density, ductility and Young’s modulus makes it the superior anti-ballistic material for impact velocity at <5 km s⁻¹. For impact velocity >5 km s⁻¹, it induces severer local deformation, and leaves no time for a well-developed distributed pattern as observed in a lower impact velocity scenario. As such, extensive elastic deformation of the nanosheet is not captured under impact, nanosheets with shorter acetylenic chains and hence greater material strength demonstrates superior impact resist. This study provides a fundamental understanding of the deformation and penetration mechanisms of monolayer GDY nanosheets under impact, which is crucial in order to facilitate their emerging applications for impact protection. (paper)

[en] Highlights: • Low dose benzene exposure leads to a decline of WBC counts. • H3K4me3 modification was enhanced upon low dose benzene exposure in vitro and in vivo. • H3K4me3 modification might mediate DNA damage response through transactivation of DDR genes. In this study, we explore whether altered global histone modifications respond to low-level benzene exposure as well as their association with the hematotoxicity. We recruited 147 low-level benzene-exposed workers and 122 control workers from a petrochemical factory in Maoming City, Guangdong Province, China. The internal exposure marker level, urinary S-phenylmercapturic acid (SPMA), in benzene-exposed workers was 1.81-fold higher than that of the controls (P P P P = 0.045) and the extent of DNA damage (% Tail DNA: β = 0.181, P = 0.022), but was negatively associated with the leukocyte count (WBC: β = −0.038, P = 0.023). The in vitro study revealed that H3K4me3 mark was enriched in the promoters of several DNA damage responsive (DDR) genes including CRY1, ERCC2, and TP53 in primary human lymphocytes treated with hydroquinone. Particularly, H3K4me3 modification was positively correlated with the expression of CRY1 in the PBLCs of benzene-exposed workers. These observations indicate that H3K4me3 modification might mediate the transcriptional regulation of DDR genes in response to low-dose benzene exposure.

[en] Highlights: • Electrical conductivity and convertibility of KAc−methanol−water solution were measured. • A reverse electrodialysis cell was built and operated with KAc−methanol−water solution. • Five impact factors on the performance of a reverse electrodialysis cell was studied. • Tested the influences of concentration, temperature and flow rate of work solutions. • Influences of solvent composition and solution compartment width were investigated. Salinity gradient energy exists between the concentrated and diluted electrolyte solutions, which can be converted to the electromotive force of a reverse electrodialysis (RED) cell. The waste solution is regenerable to restore the initial concentrations by absorbing thermal energy. The energy conversion efficiency of such a heat−to−power system is strongly influenced by the working solutions. The potassium acetate−methanol−water solution is proposed and assessed as the new candidate working fluid for the RED power system in this study firstly. The electrical conductivity of this ternary solution is fully measured and found to be influenced by the solution concentration, temperature and solvent composition. The maximum measured electrical conductivity value is 144.0 mS cm⁻¹ at 6.0 mol kg⁻¹ at 313.15 K. Furtherly, the electrical convertibility of potassium acetate−methanol−water is tested under the varying conditions freshly. The RED cell performances are influenced by the concentrations of the feeding dilute solution (recommendation: 0.02 mol kg⁻¹), concentrated solution (optimum: 6.0 mol kg⁻¹), solution flow rate (approximately 1.5 cm s⁻¹), solution temperature (20 K higher than the environmental temperature), solvent composition (aqueous methanol solvent is preferred), and width of solution compartment (100 μm is suitable). Potassium acetate−methanol−water is a competitive new working fluid with the comprehensive advantages in thermodynamic and electrochemical properties.

[en] Semi-active suspension has been increasing interests for its outstanding performance and high cost effectiveness, and the magnetorheological (MR) damper is a hotspot in these decades. For the MR damper design, here still are some farther challenges, such as, (1) how to cascade the ideal damper characteristic from full vehicle performance, and what is the ideal off-state performance and the controllable ratio; (2) how to fix the MR damper brought additional mass since the MR fluid density is three times than the traditional damper oil’s, and a promising lightweight and effective configuration and its systematical design approaches should be explored. In this article, the novel MR valve controlled damper (MRVD) and its top-down design methodology are proposed via both the configuration design and system syntheses. Results manifest that the developed MRVD prototype matches the target minibus requirement very well with consumption of 3 W drive power and 6.1 ml MR fluids, demonstrating superior dynamic performance, lightweight compact structure, low energy consumption and cost, and a promising application in semi-active suspensions. (paper)

[en] Magnetorheological (MR) devices have been investigated intensively nowadays, of which MR valve is an important and hot application with the challenges of acquiring high pressure drop within compact configurations. Hence, a novel squeeze mode based MR valve (SMRV) is proposed in this paper, with highlights of high pressure drop and low power consumption within a compact and transplantable structure. SMRV’s characteristics are studied and its core parts are designed including the initial gaps, magnetic circuit and returning spring. The uniform-saturation magnetic intensity principle is proposed and a co-simulation optimal platform is developed to optimize magnetic intensity of the SMRV dimensions. Then, a prototype is developed and its steady-state performance is evaluated. The test results demonstrate that a pressure drop of 10.8 MPa and a controllable ratio of 5 at 1.0 A applied current are achieved within a transplantable configuration. Meanwhile, SMRV only consumes 1/400 W control power to dissipate 1 W fluid power and its power–volume consumption rate, P _C · V / P _D, is 3.3 × 10² mm³, which has a brilliant application prospect in hydraulic or mechatronic systems. (technical note)

[en] Janus dendrimers have two differently functionalized segments which are located on opposite sides. They have many excellent properties and broad application prospects. In this study, poly(amido amine)/poly(acrylic acid) (PAMAM/PAA) Janus dendrimers were prepared by click chemistry. One of the first steps taken was the synthesis of N-Boc-G3.0 PAMAM dendrimers with primary amine groups at the periphery. Second, by amide coupling between propargylic acid and N-Boc-G3.0 PAMAM, PAMAM dendrimers with alkyne were successfully synthesized. After being dissolved in aqueous solutions with different pH, Janus dendrimers spontaneously form flowerlike micellar, Janus particles, and spherical micelles due to primary amino, tertiary amino, and carboxyl groups in the dendrimers. This self-assembly behavior depending on pH changes has a number of potential applications in the field of materials. (papers)

[en] Vanadium oxide, manganese oxide, tungsten oxide, and nickel oxide nanowires were investigated for their applicability as chemiresistive gas sensors. Nanowires have excellent surface-to-volume ratios which yield higher sensitivities than bulk materials. Sensing elements consisting of these materials were assembled in an array to create an electronic nose platform. Dielectrophoresis was used to position the nanomaterials onto a microfabricated array of electrodes, which was subsequently mounted onto a leadless chip carrier and printed circuit board for rapid testing. Samples were tested in an enclosed chamber with vapors of acetone, isopropanol, methanol, and aqueous ammonia. The change in resistance of each assembly was measured. Responses varied between nanowire compositions, each demonstrating unique and repeatable responses to different gases; this enabled direct detection of the gases from the ensemble response. Sensitivities were calculated based on the fractional resistance change in a saturated environment and ranged from 6 × 10"−"4 to 2 × 10"−"5%change ppm"−"1. (papers)

[en] A novel analytical investigation of magneto-rheological (MR) fluids in squeezing flows is performed and the results are validated with experimental test data. The squeeze flow of MR fluids has recently been of great interest to researchers. This is due to the large force capacity of MR fluids in squeeze mode compared to other modes (valve and shear modes), which makes the squeeze mode appropriate for a wide variety of applications such as impact dampers and engine mounts. Tested MR fluids were capable of providing a large range of controllable force along a short stroke in squeeze mode. A mathematical model was developed using perturbation techniques to predict closed-form solutions for velocity field, shear rate distribution, pressure distribution and squeeze force. Therefore, the obtained solutions greatly help with the design process of intelligent devices that use MR fluids in squeeze mode. The mathematical model also reduces the need for complicated and computationally expensive numerical simulations. The analytical results are validated by performing experimental tests on a novel MR device called an 'MR pouch' in an MR squeeze mode rheometer, both designed and built at CVeSS

[en] Highlights: • Artificial night light is a disruptor of the reproductive endocrine process of wild birds. • Low intensity night light accelerates the activation of HPG endocrine axis of tree sparrow. • High intensity night light retards the activation of HPG endocrine axis of tree sparrow. -- Abstract: Artificial light at night (ALAN) has become increasingly recognized as a disruptor of the reproductive endocrine process and behavior of wild birds. However, there is no evidence that ALAN directly disrupt the hypothalamus-pituitary-gonadal (HPG) axis, and no information on the effects of different ALAN intensities on birds. We experimentally tested whether ALAN affects reproductive endocrine activation in the HPG axis of birds, and whether this effect is related to the intensity of ALAN, in wild tree sparrows (Passer montanus). Forty-eight adult female birds were randomly assigned to four groups. They were first exposed to a short light photoperiod (8 h light and 16 h dark per day) for 20 days, then exposed to a long light photoperiod (16 h light and 8 h dark per day) to initiate the reproductive endocrine process. During these two kinds of photoperiod treatments, the four groups of birds were exposed to 0, 85, 150, and 300 lux light in the dark phase (night) respectively. The expression of the reproductive endocrine activation related TSH-β, Dio2 and GnRH-I gene was significantly higher in birds exposed to 85 lux light at night, and significantly lower in birds exposed to 150 and 300 lux, relative to the 0 lux control. The birds exposed to 85 lux had higher peak values of plasma LH and estradiol concentration and reached the peak earlier than birds exposed to 0, 150, or 300 lux did. The lower gene expression of birds exposed to 150 and 300 lux reduced their peak LH and estradiol values, but did not delay the timing of these peaks compared to the control group. These results reveal that low intensity ALAN accelerates the activation of the reproductive endocrine process in the HPG axis, whereas high intensity ALAN retards it.