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High-performance relaxor-PbTiO 3 ferroelectric crystals have been widely applied in transduces, sensors and so on. The ferroelectric phase transition temperature restricts their application in automobile, deep oil-well detection and aerospace which requires high thermal stability. Decreasing the effects of ferroelectric phase transition is a promising strategy for improving the thermal stability. Here, the design strategy is structural regulation via rare earth doping tetragonal Pb(In 1/2 Nb 1/2)O 3 –PbTiO 3 (PIN-PT) crystals. The d 33 , k 33 and T C of [001] c -oriented Nd-PIN-PT crystals are 750 pC/N, 87%, 250 °C. Compared with the d 33 of tetragonal 0.61PIN-0.39 PT crystals (540 pC/N) and tetragonal 0.35PIN-0.26 Pb(Mg 1/3 Nb 2/3)O 3 (PMN)-0.39 PT crystals (530 pC/N), the d 33 of Nd-PINT crystals enhance by 39% and 41%. In addition, Nd-PIN-PT crystals have Q m of 110, which is larger than rhombohedral relaxor-PbTiO 3 ferroelectric crystals (~50). Although the d 33 of Nd-PIN-PT crystals is lower than that of rhombohedral relaxor-PT ferroelectric crystals, the d 33 and k 33 are stable up to 250 °C, which is higher than tetragonal PIN-PMN-PT crystals (210 °C). The high thermal stability of piezoelectric properties is related to the high thermal stability of domain after poling. This work provides a design strategy for high thermal stability ferroelectric crystals. [ABSTRACT FROM AUTHOR]

The modified inverse micelle approach was used to create nickel-doped mesoporous manganese oxides (Ni-MM). These novel catalysts showed much higher reactivity to activating PMS than the pristine mesoporous manganese oxides, and 5% doping ratio (Ni/Mn) would lead to best degradation efficiency in the PMS/Ni-MM system. X-ray diffraction (XRD) displayed that the crystal composition of manganese oxides would be changed and scanning electron microscope (FESEM) presented that the surface morphology was transformed from spherical deconstruction to sponge-like particles since Ni was doped into MM. Mn2+, Mn3+ and Mn4+ were coexisted in 5%Ni-MM, and Ni in the material was +2. The operating conditions such as catalyst dosage, PMS dosage, TCH concentration and beginning pH. Under the ideal reaction conditions for 5%Ni-MM/PMS system, the TCH degradation efficiency could be 86.79% in 30 min, and it could be used in the pH range (3-11). In the presence of Cl−, SO 4 2−, CO 3 2−, PO 4 3−, HCO 3 −, humic acid (HA) and natural water bodies, TCH degradation efficiencies could still be greater than 80%. Quenching experiments indicated that O 2 ·-, 1O 2 , SO 4 ·- and ·OH contributed to TCH degradation in the 5%Ni-MM/PMS system. The intermediates were identified by LC-MS, and the pathways for 5%Ni-MM/PMS system degradation of TCH were conjectured. [Display omitted] • A novel mesoporous nickel-manganese oxides were prepared by reverse micelle method. • The catalyst has a higher activation effect on PMS. • Excellent reusability of mesoporous nickel-manganese oxides were confirmed. • TCH removal efficiency achieved 86.79% under 40 mg/L(TCH), dosage = 0.5 g/L(catalyst), 0.6 g/L(PMS). [ABSTRACT FROM AUTHOR]

High-mobility group box 1 (HMGB1) translocation and release, which is involved in several tissue types of ischemia-reperfusion injuries, activate innate immunity by inducing proinflammatory cytokine production through its interaction with toll-like receptors (TLRs). Our objective was to determine the role of HMGB1 and the degree of activation of TLR-related signal transduction pathways in hypoxia/reoxygenation (H/R)-induced proinflammatory cytokine production and intra-islet graft inflammation. After islets are exposed to hypoxia-reoxygenation for 24 h, TLR2/4 expression and TLR-mediated signaling was up-regulated in islets, and HMGB1 was translocated from the nucleus to the cytoplasm and released to the extracellular space. With H/R exposure, proinflammatory cytokine production (IL-1β and TNF-α) and islet injury were significantly increased, and these effects depend on TLR2/4 signaling pathways. Exogenous HMGB1 also induces islet inflammation and increases the phosphorylation of STAT3, p38 and IκBα in wild-type islets. TLR2 deficiency in TLR2-KO islets resulted in the inhibition of IL-1β production and STAT3/p38 phosphorylation after HMGB1 exposure. TLR4 deficiency in TLR4-KO islets resulted in the inhibition of TNF-α production and IκBα phosphorylation after HMGB1 exposure. Pre-incubation of the STAT3, p38, or NF-κB inhibitors significantly inhibited HMGB1-induced IL-1β or TNF-α production in islets, but the effect of HMGB1 or H/R-induced islet injury was not counteracted by a separate treatment of the STAT3 inhibitor, p38 inhibitor, or NF-κB inhibitors. HMGB1 inhibition by ethyl pyruvate or blockade by neutralizing antibodies significantly decreased the phosphorylation of STAT3, p38 and IκBα, the production of IL-1β and TNF-α, and the islet injury in wild-type islets after exposure to H/R and significantly improved early islet graft failure. Thus, our results suggest that HMGB1 released from H/R induced islets works in an autocrine manner to up-regulate STAT or p38 and augment IL-1β production via TLR2, and up-regulate NF-κB and augment TNF-α production via TLR4 in intra-islet, which are associated with H/R-induced islet injury and early graft failure. [ABSTRACT FROM AUTHOR]

Park-level integrated energy system, as a energy coupling component of urban energy systems, plays a great role in promoting various types of energy coupling. Traditional planning method of park-level integrated energy system does not allocate reasonable equipment capacity according to the difference of load level in different time sequence stages, resulting in redundancy at the initial stage and shortage at the final stage. In this paper, based on the concept of multi-stage planning, a multi-stage equipment capacity configuration planning model of park-level integrated energy system including electricity, gas and heat is proposed, the objective function of which includes cost of investment, operation, maintenance and compensation. On this basis, the influence of thermal flexible loads caused by the transmission delay of heat supply network and the ambiguity of user's temperature perception, as well as the influence of electrical flexible loads such as shiftable load, transferable load and curtailable load on equipment capacity configuration are considered. The simulation results show that the idea of multi-stage planning can reduce equipment capacity configured in the preliminary stage and increase equipment capacity configured in the later stage, which conforms to the change law of load level. The introduction of flexible loads can reduce the amount of equipment capacity configured in each stage without destroying the balance between energy supply capacity and load level by optimizing the load curve structure. [Display omitted] • A multi-stage modeling method of PIES is proposed based on load characteristics. • A multi-stage coupling model coupled by unified objective function is established. • Electrical and thermal flexible loads are introduced to optimize the load structure. • The impact of PV and loads uncertainty is considered in the planning scheme. [ABSTRACT FROM AUTHOR]

The regular domain structure is beneficial to the enhancement of piezoelectric properties of relaxor-PbTiO 3 ferroelectric crystals after alternating current poling (ACP). However, one shortcoming of ACP is that there are some non-rotational domains. Another is that ACP has no effect on polar axis-oriented crystals. Therefore, ACP is not very satisfactory for the morphotropic phase boundary (MPB) composition. Here, we demonstrate a pulse poling (PP) method that can lead to substantially increase the piezoelectric coefficient d 33 of MPB region Pb(In 1/2 Nb 1/2)O 3 -PbTiO 3 (PIN-PT) single crystals. The d 33 and free dielectric permittivity εT 33 /ε 0 of ACP [001] c -oriented 0.65PIN-0.35PT single crystals are 1490 pC/N and 3360, which are smaller than DCP sample (1640 pC/N and 3620). The d 33 and εT 33 /ε 0 after PP method are 2400 pC/N and 5390, having 61% and 60% improvement compared with ACP method. This work presents a new domain engineering method for achieving high piezoelectricity of these MPB region ferroelectric crystals. A new poling method called pulse poling was proposed for improving the piezoelectric properties of MPB region relaxor-PT single crystals. The d 33 and εT 33 /ε 0 of 0.65PIN-0.35PT single crystals after PP method are 2400 pC/N and 5390, having 61%, 60% and 46% and 49% higher than that of ACP and DCP samples [Display omitted]. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 thin films were deposited by reactive radio frequency magnetron sputtering of Ti target at low working pressure (1mTorr) and various O2 and Ar flow ratios (R O2 =O2/(O2 +Ar)). Properties of TiO2 films were measured by field emission scanning electron microscopy, atomic force microscopy, X-ray diffractometry, UV–VIS transmission spectroscopy, X-ray photoelectron spectroscopy and evaluated by contact angle analysis. Well defined columnar structure with rough surface was obtained at relatively lower R O2. As R O2 increased, the oxygen vacancies in the films decreased and the stoichiometric ratio of O/Ti changed from 1.79 to 1.98. Transition from anatase to rutile phase was observed with increase in R O2. The optical bandgap showed a red shift with increase in R O2 . In addition, the film with co-existing of rutile and anatase showed a high Urbach tail. Lower R O2 resulted in higher photo-hydrophilicizing efficiency due to the change in morphology, structure and composition. However, very low R O2 (less than 10%), which led to transition mode, resulted in poor photo-hydrophilicizing efficiency. [Copyright &y& Elsevier]

Abstract: A modified Hertz contact law is proposed for the contact problem of a laminated plate indented by a rigid sphere, which involves the effects of the thickness, in-plane dimensions and boundary conditions of the plate. The model shows that the deflection difference between the center and the edge of the contact area is a key factor dominating the effects of these variables on the force–indentation response. The modified contact law is assumed to follow the same mathematical formulation as the Hertz law. However, the contact stiffness is no longer constant but varies as a function of the contact force due to the thickness effect. The predictions of the force–indentation response show improved agreement over early work by Yang and Sun. Over the present analysis range, the thickness effect may be negligible if the plate thickness is greater than 2mm. On the other hand, the thickness has a more significant effect on the force–indentation response if the plate thickness is less than 2mm. Moreover, the in-plane dimensions and the boundary conditions of the plate show little influence on the force–indentation response within the present scope of analysis. [Copyright &y& Elsevier]

The aim of this study was to investigate whether pedicled ligament flaps (PLF) covering around the hepatic and gastroduodenal artery stump can provide better clinical outcomes in pancreatoduodenectomy (PD). We conducted a comprehensive search of databases (inception to January 2023) to identify studies comparing PD with or without PLF covering the skeletonized arteries. The perioperative and postoperative outcomes were compared. Pooled odds ratios (ORs) with 95 % confidence intervals (CIs) were calculated using fixed-effects models. Ten studies were included in the qualitative synthesis. Six studies with 3538 patients met the inclusion criteria for the meta-analysis. Patients in the PLF group had a significantly lower rate of PPH from the hepatic artery or gastroduodenal artery stump (H/G PPH) (OR: 0.41; 95 % CI, 0.22–0.75; P < 0.01) and overall PPH (OR: 0.65; 95 % CI, 0.46–0.93; P = 0.02). There were no significant differences between the two groups in terms of morbidity, grade B/C postoperative pancreatic fistula (B/C POPF), delayed gastric emptying (DGE), reoperation, or mortality. Prophylactic pedicled ligament flaps covering around the skeletonized arteries significantly reduced overall PPH and H/G PPH, and it seemed to have no obvious influence on other complications. [ABSTRACT FROM AUTHOR]

The graphene nanoplatelets reinforced ADC12 composites (GNPs/ADC12) were successfully fabricated by ultrasonic assisted casting. The aging behavior, microstructure and mechanical properties of GNPs/ADC12 composites were investigated in this study. It was found that during aging treatment, Al 2 Cu precipitates preferentially nucleated at the GNPs/Al interfaces and dislocations induced by GNPs. This was mainly because the dislocations and interfaces could act as preferred nucleation sites for Al 2 Cu precipitates and diffusion channels for Cu element. And, the addition of GNPs could result in the finer grains, more GNPs/Al interfaces and high density dislocations, thus promoting the precipitation process of GNPs/ADC12 composites. Moreover, GNPs could improve the aging strengthening effect of the composites because of the pinning effect of GNPs on grain boundaries. As a result, the yield strength of peak aged GNPs/ADC12 composites was 245.8 MPa, which was 69.9% higher than that of ADC12 alloy. The peak aged composites were mainly strengthened by dislocation strengthening mechanism, which accounted for 62.3% in total strength contributions. • Al 2 Cu precipitates tend to nucleate at the GNPs/Al interfaces and dislocations. • GNPs can promote the precipitation of Al 2 Cu phase. • GNPs can improve the aging strengthening effect of the composites. • The composites are mainly reinforced by the dislocation strengthening mechanism. [ABSTRACT FROM AUTHOR]

Abstract: A bottom-up technique using an aqueous solution method was adopted to fabricate a bio-mimicked antireflection (AR) coating for a CuInGaSe2 (CIGS) solar cell. On controlling the morphology of the solution-grown zinc oxide (ZnO) nanostructure the average reflectance of the CIGS solar cell employing the bio-mimicked AR coating decreased from 6.14% to 1.46%, and the efficiency of the solar cell increased from 10% to 11.5%. The mechanism by which the solar cell′s efficiency was enhanced is thought to be the effect of the gradual increase in the refractive index between air and the top electrode due to the insertion of the ZnO nanostructure. [Copyright &y& Elsevier]

Abstract: Quasi-static indentation tests on composite laminates have been performed. Thermal deply and C-scan techniques are used to observe the internal damage characteristics of laminates induced by static indentation. The results indicate that the dent depth increases slowly and almost linearly as the force is lower than its maximum. The observation shows that the damage induced at this loading stage includes matrix cracking and delamination only. Once the force exceeds the maximum, the dent depth increases sharply while the force remains almost unchanged. Deply test results demonstrate that the transition to rapid increase in dent depth is due to the fiber breakage produced at this loading stage. The results also indicate that the damage resistance of a composite laminate can be characterized by the maximum contact force. On the basis of this principle and test results, it is concluded that the damage resistance of toughened composite is much higher than that of brittle one. [Copyright &y& Elsevier]

In this study, a WO 3 /g-C 3 N 4 composite photocatalyst was synthesized via a hydrothermal method and characterized for its potential application in photocatalytic H2 generation from PET degradation. XRD analysis revealed that the hexagonal WO 3 crystal structure was achieved after 10 h of hydrothermal time, with particles of suitable size for uniform loading on the g-C 3 N 4 surface. SEM images showed the successful loading of WO 3 nanorods onto the g-C3N4 surface, significantly increasing the specific surface area. FTIR and UV–vis diffuse reflectance spectroscopy confirmed the formation of a Z-type heterojunction between WO 3 and g-C 3 N 4. Photoluminescence measurements indicated a reduced rate of electron-hole pair recombination in the composite. The 30% WO 3 /g-C 3 N 4 composite demonstrated a high H 2 evolution rate of 14.21 mM and excellent stability in PET solution under visible light irradiation. 1H NMR and EPR spectroscopy analyses revealed the degradation of PET into small molecular compounds and the generation of active radicals, including ·O 2 −, during the reaction. Overall, the WO 3 /g-C 3 N 4 composite exhibited promising potential for photocatalytic H 2 production and PET degradation. [Display omitted] • C 3 N 4 /WO 3 photocatalyst were successfully synthesiszed • Photocatalytic removal of microplastics from water activated by visible light. • The by-products from microplastics degradation are considered to have low toxicity. • Degradation efficiency and applied system limitations are proposed. [ABSTRACT FROM AUTHOR]

Objectives The assessment of acute pancreatitis severity on admission currently remains a challenge to clinicians. A single, rapid biochemical marker would be preferable to clinical and radiological scoring systems. The aim of this study was to undertake a meta-analysis on the value of carboxypeptidase-B activation peptide (CAPAP) in predicting severity of acute pancreatitis on admission. Methods Major databases and trial registries were searched to identify all relevant studies from January 1998 to March 2015. Pooled sensitivity, specificity and the diagnostic odds ratios (DOR) with 95% confidence interval (CI) were calculated for each study and were compared to other biomarkers, if included, within the same study. Summary receiver-operating curves (ROC) were conducted and the area under the curve (AUC) was evaluated. Results In total, six studies were included. At the time of admission, the AUC of serum CAPAP for predicting severity of acute pancreatitis was 0.86 with pooled sensitivity, specificity and DOR of 0.90, 0.70 and 19.08, respectively. When serum CAPAP was compared with urinary CAPAP, the AUC, pooled sensitivity, specificity and DOR were 0.69 vs 0.88, 0.90 vs 0.81, 0.68 vs. 0.77 and 17.96 vs. 18.58, respectively. Similarly, the AUC, pooled sensitivity, specificity and DOR of serum CAPAP vs maximal serum C-reactive protein within the first 3 days of admission were found to be 0.97 vs. 0.82, 0.92 vs. 0.88, 0.81 vs 0.68 and 37.90 vs. 18.80, respectively. Conclusions Both serum and urinary CAPAP have the potential to act as a stratification marker on admission in predicting severity of acute pancreatitis. [ABSTRACT FROM AUTHOR]

The TiO 2 nanoparticles-coated CNTs (TiO 2 @CNTs) were used as reinforcement to fabricate the 7075-TiO 2 @CNTs composites via ultrasonic-assisted casting, then the composites were adopted T6 treatment. The microstructures and wear performance were investigated in detail. The TiO 2 @CNTs could promote the refinement of α-Al grains, reducing the average size by 60.7%. With the addition of 1.0 wt% TiO 2 @CNTs and introduced T6 treatment, the wear rates have maximally decreased by 48.2% and 69.2%, respectively. The self-lubrication and refinement strengthening effect of CNTs improved the wear resistance, and the strong interfacial bonding between nanoscale MgZn 2 precipitates and α-Al further enhanced the tribological properties. The effects of vertical load and sliding velocity on tribological morphology of T6 treatment composites were investigated, demonstrating that with the increase of vertical load, the wear rate and micro-crack tendency increased. Meantime, with the increase of sliding velocity, both the wear rate and the surface roughness showed a decreasing and then increasing trend. The main wear regime was abrasive wear combined with slight oxidation at lower velocities, while delamination wear combined with severe oxidation at higher velocities. • The TiO 2 @CNTs could promote the refinement of α-Al grains, reducing the average size by 60.7%. • The self-lubrication and refinement strengthening effect of CNTs improved the wear resistance. • The strong interfacial bonding between nanoscale MgZn 2 precipitates and α-Al further improved the tribological properties. • The wear rate and micro-crack tendency on the worn surface increased with the increase of vertical load. • The wear rate and the surface roughness showed a decreasing and then increasing trend with the increase of sliding velocity. [ABSTRACT FROM AUTHOR]