Superhydrophobic nanostructured coatings are a promising technology in construction engineering. This study developed a hydrophobic film through a simple mixing method, utilizing kaolin and ...polytetrafluoroethylene as additive particles, 1
,1
,2
,2
-perfluoro-decyl triethoxysilane as a modifier, and epoxide resi
and polyamide curing agent as adhesives. By controlling variables, it was determined that the C
EP coating immersed in a 3.5 wt% NaCl solution for 1, 3, and 7 days exhibited the maximum impedance radii of 47,373, 20,334, and 1,982 Ω·cm
, respectively. It also demonstrated the highest Bode modulus values, the largest
, and the smallest
. Furthermore, after 300 h in a salt spray chamber with a 3.5 wt% NaCl solution, the C
EP coating showed no rust spots or bubbles, demonstrating its excellent corrosion resistance. Moreover, wear resistance tests and self-cleaning experiments were conducted on the C
EP coating. The results showed that after 100 friction cycles, the surface exhibited no visible scratches, and the contact angle of the coating decreased by only 4°. Additionally, neither soil particles nor dirty water adhered to the coating, indicating that the C
EP hydrophobic coating possesses not only excellent corrosion resistance but also superior wear resistance and self-cleaning capabilities.
Thrombosis is the main reason for the failure of ventricular assist devices (VADs). It has been acknowledged that the platelet activation induced by the nonphysiological blood flow leads to the ...increased thrombotic risk. However, due to the complicated influence of the VADs’ flow field and the difficulty in real‐time in situ observation, the mechanisms and process of thrombus formation in VADs remain unclear. In this work, the process of thrombus formation in VADs in vitro experiments is observed. The thrombus is found to form on the middle of the inlet guide vanes first and it is mainly caused by the immediate activation of platelets induced by the high shear rate of the flow field around the vanes and also affected by the rotation of the impeller. Then, subsequent thrombus is found in the tail of guide vanes and around the axle journal, where the blood flow is stagnated and the platelets are activated by the accumulated bioagonists. These findings clarify that the thrombus formed on the inlet guide vanes and the axle journal are dominated by two different mechanisms. This work provides unique insights into the initial formation of the thrombus on VADs and helps to reduce the thrombotic risk.
The thrombus formation process in ventricular assist devices (VADs) is observed in real time. Two different mechanisms, shear‐induced platelet activation and bioagonist‐induced platelet activation, exist in different parts of the VAD, which affect the formation sequence, the position, and the composition of the thrombus. These insights are instrumental in selecting suitable designs and anticoagulation strategies for VADs.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The bit holds paramount importance as a rock-breaking tool in petroleum and natural gas industry drilling, rock drillability grading using a polycrystalline diamond composite (PDC) bit is the key ...basis for individualized design and selection of a bit and optimization of drilling parameters. This is especially true for formations that are above medium hard. However, the petroleum and natural gas industry standard “rock drillability measurement and gradation method” issued and implemented in China has obvious defects. For rocks above medium hard, the measurement is often invalid and drillability grade data cannot be obtained. Through many drillability measurements on rock samples of various lithologies, it has been found that the main reasons for the ineffectiveness of measurements of rock above medium hard are that the standard weight on the bit (WOB) is too low and that the structural parameters of PDC microbits are unreasonable. To solve these problems, we first studied the influence of the side rake of the microbit cutter on the interference state and proposed an optimal microbit side rake. This eliminates the possibility of interference between the microbit cutter and the rock. Second, we conducted rock drilling experiments on five kinds of rock under various WOB values. The experimental data show that there is a linear relation between the variable-weight drillability level and the WOB. We put forward a new method of drillability measurement and grading, which is based on the measurement of drilling pressure grading, equivalent conversion grading, or independent grading. This method not only effectively solves the problem of drillability measurement of medium-hard and harder rocks but is also compatible with past soft-rock measurement data.
•Studies the influence of the side rake of the microbit cutter on the interference state and proposed an optimal microbit side rake.•The experimental data shows that there is a linear relation between the variable weight drillability level and the WOB.•A new method of drillability measurement and grading is put forward, which is based on the measurement of drilling pressure grading, equivalent conversion grading, or independent grading.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Display omitted
•A porous carbon material with higher nitrogen-dopped content of 5.29% was obtained from poly(Schiff-base).•The specific surface area for N-PCM-7 reached up to 1164 m2·g−1 after ...carbonizing and etching.•The symmetrical supercapacitor fabricated with N-PCM-7 showed a maximum specific energy of 15.97 Wh·kg−1 and capacitance retention rate of 89.4% after 10,000 cycles at 1 A·g−1.
In the design of carbon-based electrode materials, the introduction of heteroatoms and fabrication of the hierarchical porous structures are two important strategies to improve the performance of supercapacitors. In this investigation, based on the dispersion polymerization of 1,2,4,5-benzenetetramine tetrahydrochloride and terephthalaldehyde in ethanol, followed by etching with KOH and carbonizing at 500–800 °C of the resulting microspheric poly(Schiff-base), a honeycomb-like N-doped porous carbon material (N-PCMs) was synthesized. The specific surface area of porous N-PCMs was measured as higher as 1164 m2·g−1. In 1 M Na2SO4 electrolyte, N-PCM-7 (sample carbonized at 700 °C) showed higher specific capacitance and good rate performance (297 F·g−1 at 0.5 A·g−1, and 186 F·g−1 at 20 A·g−1). To get closer to the practical application, the button-type symmetrical supercapacitors (N-PCM-7D) have made from the N-PCM-7, for this supercapacitor, its specific capacitance was determined to be up to 158 F·g−1 under the condition of 0.5 A·g−1. Furthermore, the supercapacitor still has a capacitance retention rate of 89.4% after 10,000 cycles at 1 A·g−1, indicating higher-performance for energy storage and the potential applications.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Liquid infused surfaces (LIS) hold remarkable potential in anticoagulation. However, liquid loss of LIS in the bloodstream remains a challenge toward its clinical application. Here, micronano ...hierarchy structures are obtained on the titanium alloy substrate by regulating the microspheres' distribution. When the gap between the microspheres is smaller than the diameter of the red blood cell (RBC), the LIS is more stable under the blood wash and presents a better anticoagulation performance. The proper interval is found to prevent the RBCs from entering the gap and remove the liquid on the surface. The retained thickness of the liquid film is measured by the atomic force microscopy (AFM) technique. The LIS is applied on the front guide vane of an artificial heart pump and exhibits significant improvement on anticoagulation in the blood circulation in vitro for 25 h. The techniques and findings can be used to optimize the anticoagulation performance of LIS-related biomedical implant devices.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
Here we have performed molecular dynamics simulations to investigate the structures, dynamics, and hydrogen bonds (HBs) of the imidazolium-based ionic liquid (IL) mixture containing equimolar ...1-ethyl-3-methylimidazolium tetrafluoroborate (EmimBF4) and 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF6) around the single-walled carbon nanotubes (CNTs) with three different diameters of 5.42, 10.85, and 21.70 Å. Our simulation results reveal for the first time that the BF4− and PF6− anions have an obvious competitive HB behavior for the IL mixture around the CNTs, and such HB competition can be further enhanced as the CNT diameter increases. The HBs between the PF6− anions and cations are always more and stronger than those between the BF4− anions and cations regardless of the CNT diameter, although the enhanced HBs are found for both kinds of anions in the first solvation shell around larger CNTs. Nevertheless, the interfacial PF6− anions show a larger HB enhancement than the corresponding BF4− anions as the CNT diameter increases. Besides the competitive interactions between the different anions and the CNT, such competitive HB behavior in the IL mixture leads to more PF6− anions but less BF4− anions aggregating around the larger CNTs, which is significantly different from the previous aggregation behavior of pure ILs around the CNTs. Furthermore, there exist the opposite diameter-dependent changes of average HB number per cation with the BF4− and PF6− anions. In addition, the enhanced HBs between cations and anions around the larger CNTs result in slower rotations of both the BF4− and PF6− anions and more pronounced orientational distribution of both the imidazolium cations in the first solvation shell around the CNTs.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
In this study, we developed a strategy about synergistic enhancement and in-situ composite between polymer and carbon to prepare an electrode material for the high-performance supercapacitor. ...Specifically, Dobner polymerization was selected to synthesize a conjugated polyquinoline derivative (PQLD), and along with the simultaneous introduction of graphene oxide (GO) in the reaction system for a new in-situ electrode material (PQLD-GO). The strengthened intermolecular interactions among pyridine/carboxyl groups from PQLD and carboxyl/hydroxyl groups from GO, including π-π stacking, synergistically enhance the electron/ion transport and Faraday reactions of PQLD-GOs composites. The experimental results showed that the electrochemical performance for PQLD-GOs composites is reasonably optimized as the optimal amount of 10% GO. Far different from the specific capacitance of 20 F g−1 for pure PQLD and 21 F g−1 for pure GO, the specific capacitance of PQLD-GO-10% composite is as high as 320 F g−1 in the three-electrode test, indicating a significant synergistic enhancing effect. In the two-electrode measurement system, the energy density of PQLD-GO-10% is 7.4 Wh kg−1, and the power density is 125 W kg−1. Even after 10,000 cycles at 10 mV s−1, the specific capacitance of PQLD-GO-10% remained 87.9%. Furthermore, the synergistic effect between PQLD and GO was also revealed through several comparative experiments such as simple mixing, replacement of non-conjugated polyquinoline or carbon nanotube and so on.
Display omitted
•Polar conjugated polyquinoline derivative (PQLD) was facilely synthesized by Dobner polymerization.•In situ composite between PQLD and GO in the polymerization system leads to a high-performance electrode material (PQLD-GOs).•Synergistic effect between PQLD and GO confers the enhanced specific capacitance and long cycle life for symmetric supercapacitor.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Hemorrhage is the phenomenon of blood loss caused by vascular trauma or other pathological reasons, which is life-threatening in severe cases. Because microhemorrhage is difficult to visually monitor ...and pre-treat
in vivo
, it is necessary to establish
in vitro
prediction methods to study the hemostasis mechanism in different physiological environments. In this study, a microfluidic bleeding model was developed to investigate the effect of blood flow shear on microvascular hemostasis. The results indicated that the regulation of blood shear rate on platelet aggregation affected the growth and morphology of hemostatic thrombus, and finally regulated the process of hemostasis. This
in vitro
model is significant to studies on hemostatic mechanisms, a reliable prediction of microhemorrhages, and an adjustment of the treatment scheme.
•Passerini reaction binds indole and thiophene in the form of covalent bonds.•The as produced poly(indole/thiophene) exhibits excellent electrochemical energy storage performance, in terms of ...specific capacitance, energy density, power density and cycle stability.•The polymer also demonstrates strong affinity with Fe3+, which offers high sensitivity for Fe3+ iron detections.
In this paper, a series of monomers (M1-M7) were facilely synthesized by Passerini reaction and the subsequent in-situ polymerization led to the formation of the conductive poly(indole/thiophene)s (P1-P7). Among P1-P7, it was found through the comparison that P7-P with a higher conjugated system exhibits an outstanding specific capacitance of 1170 F g−1 (scan rate 1 mV s−1), power density of 2614.4 W kg−1 and energy density of 56.5 Wh kg−1 (5 A g−1). The capacitance performance of P7-P complexed with Fe3+ system is further increased by 130 F g−1 because of the redox reaction of Fe3+. Using the chronoamperometry, the minimum detection limit of polymer P7-P for Fe3+ is 3 × 10−5 M. In summary, the facile synthesis of the conductive poly(indole/thiophene) polymers, their excellent energy storage and Fe3+ detection performance, open an opportunity for functional polymers in the energy storage and sensor applications.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
