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Casing reliability is essential for the high-temperature high-pressure (HTHP) wells. The complicated downhole geological environment, high casing external load during the drilling stage, and annulus pressure in the production stage may all lead to casing collapse and wellbore integrity failure. Thus, it remains a hot topic to quantitatively evaluate the casing reliability throughout the whole life cycle (WLC) of HTHP wells. In this paper, a WLC quantitative evaluation method of casing reliability of HTHP wells in the whole borehole section is established based on the Monte Carlo simulation and the stress–strength interference theory. More specifically, WLC casing load is calculated by integrating the annulus pressure, casing load under non-uniform in situ stress, and the drilling extreme conditions. The casing strength calculation model of HTHP wells is then established by the K-T formula, while considering the temperature effect on casing strength to compute the casing reliability. The proposed method is applied in an HTHP gas well in the South China Sea. The results indicate that, under the hollowing degrees with allowable safety factors, there is still some risk in the casing running and lost circulation conditions. The failure risk at the weak points of each spud is within 0.08–0.2 in the casing running condition and within 0.1–0.5 in the lost circulation condition. For the production stage, before and after annulus pressurization, the overall trend of the casing safety factor of anti-internal-pressure remains the same and decreases with increasing well depth. The weak points exist at the inner cement surface or boundary point of different wall thickness casings. The risk of casing extrusion after annulus pressurization increases with decreasing well depth. Due to the lack of consideration of annulus pressure and uncertainty in the conventional casing-strength design methods, there is a possible failure risk at the casing weak points after annulus pressurization, where the reliability at the weak points on both side casings of annulus C is within 0.55–0.67 under annulus pressure 19MPa. The research verifies that the casing strength design should leave a margin in the HTHP environment to avoid high temperatures reducing reliability. Under the leak-prone strata condition, the casing strength at weak points should be strengthened accordingly. The casing-strength design considering annulus pressure and uncertainty will improve the casing reliability. In addition, this method can also be used to calculate the maximum allowable annulus pressure and the maximum allowable hollowing degree under the existing production and drilling plans, thus helping to optimize production and casing strength design.

For perovskite quantum dot (PQD)-based solar cells, insertion of a proper polymer/PQD bulk heterojunction (BHJ) connecting layer between PQDs and an organic hole-transporting layer (HTL) may improve the power conversion efficiency (PCE). However, it is unknown whether the hole transfer from PQDs to the polymer plays an important role for the carrier extraction to circumvent the obstacle of direct hole transfer from PQDs to the HTL. In this work, we have used ultrafast transient absorption spectroscopy (TAs) to investigate the charge transfer in polymer/PQD BHJ films composed of FAPbI3(FA = CH(NH2)2) QDs and conjugated polymers (PBDB-T, PTB7, P3HT). The TA signals originated from PQDs decay much faster in the PBDB-T/PQD BHJ film compared to the pure PQD film, and a characteristic photoinduced bleaching signal of PBDB-T is emergent after the selective excitation of FAPbI3QDs, which prove a substantial hole transfer from PQDs to PBDB-T. The hole transfer efficiency is calculated to be 68.4%. In contrast, PTB7 and P3HT have negligible influence on the TA signals of PQDs under selective excitation, indicating ineffective hole transfer in these two BHJ films. The FAPbI3QD solar cells employing the PBDB-T/PQD BHJ as the active layer possess enhanced PCE compared to that using the pure PQD layer, whereas the decreased PCE is obtained for devices with the BHJ of inefficient hole transfer. Our results provide insights that adding an optimal amount of conjugated polymer with an effective hole transfer from the PQDs is important to facilitate overall charge carrier extraction in the PQD-based solar cells.

We report the large-scale transfer process for monocrystalline CsPbBr3thin films prepared by chemical vapor deposition (CVD) with excellent optical properties and stability. The transfer process is robust, simple, and effective, in which CsPbBr3thin films could be transferred to several substrates and effectively avoid chemical or physical fabrication processes to damage the perovskite surface. Moreover, the transfer process endows CsPbBr3and substrates with atomically clean and electronically flat interfaces. We utilize this transfer process to realize several optoelectronic devices, including a photonic laser with a threshold of 61 μJ/cm2, a photodetector with a responsivity of 2.4 A/W, and a transistor with a hole mobility of 11.47 cm2V–1s–1. High device performances mainly originate from low defects of high-quality single-crystal perovskite and seamless contact between CsPbBr3and target substrates. The large-scale nondestructive transfer process provides promising opportunities for optoelectronic applications based on monocrystalline perovskites.

We have studied four 2D layered perovskites, including OA2PbI4(RP phase), ODAPbI4and BDAPbI4(DJ phase), (GA)MAPbI4(ACI phase), where OA is [(CmH2m+1)NH3](m= 8), ODA is [NH3(CH2)mNH3](m= 8), BDA is [NH3(CH2)mNH3](m= 4), and GA is [C(NH2)3]; RP, DJ, and ACI means Ruddlesden–Popper, Dion–Jacobson and alternating cations in the interlayer, respectively. The temperature dependence of absorption and photoluminescence (PL) spectra have been measured. From which the average phonon energy (electron-phonon interaction strength) is analyzed as around 34 (80), 47 (184), 50 (402), and 63 (758) with the unit of meV for OA2PbI4, ODAPbI4,BDAPbI4, and (GA)MAPbI4, respectively. Larger phonon energy indicates the involvement of more phonons in organic spacer layer, with the corresponding stronger electron-phonon interaction. Furthermore, ultrafast transient absorption spectroscopy proves that, when the excitation photon energy is serval hundred meV higher than bandgap, the excitons still are the major photoexcitations in OA2PbI4, but polarons are major one in ODAPbI4, BDAPbI4, and (GA)MAPbI4films, no matter the excitonic transitions dominate the absorption at their band edges. This work proves the organic spacers can regulate electron–phonon interaction then optoelectronic properties in 2D perovskites profoundly, which have implications toward future rational design for relevant devices.

Joining titanium alloy with carbon fiber reinforced thermoplastic (CFRTP) is one of the hot subjects in the automotive and aerospace industries. To improve the joint strength of TC4/CFRTP PA6, this study combined the surface treatment of TC4 alloy, including laser ablation, Silane Coupling Agent (SCA) treatment, and interfacial PA6 adhesive. The results showed that the pretreatment and the laser texturing induced the micro-scale porous and macro-scale groove grid structure, respectively. The superhydrophilicity of the laser texturing as well as amino polar groups induced by SCA treatment promoted the adhesion of the thermoplastic PA6 melt into the microstructure of the TC4 alloy surface. The mechanical interlocking and hydrogen bonding between TC4 alloy and CFRTP PA6 significantly improved the shear strength of the TC4/CFRTP PA6 joint (17.5 MPa). Furthermore, with the incorporation of interfacial PA6 adhesive, the joint strength was further enhanced, and the damage of the TC4/CFRTP PA6 joint was transformed from interfacial to interlaminar CFRTP PA6.

Antiferromagnets (AFMs) have the potential to push spintronic devices from a static condition or gigahertz frequency range to the terahertz range for the sake of high-speed processing. However, the insensitivity of AFMs to magnetic fields makes the manipulation of spin currents difficult. The ultrafast generation of the spin current in ferromagnet/heavy-metal (HM) structures has received a lot of attention in recent years, but whether a similar scenario can be observed in an AFM/HM system is still unknown. Here, we show the optical generation of ultrafast spin current in an AFM/HM heterostructure at zero external magnetic field and at room temperature by detecting the associated terahertz emission. We believe that this is a common phenomenon in antiferromagnets with strong nonlinear optical effects. Our results open an avenue of fundamental research into antiferromagnetism and a route to AFM spintronic devices.

Bulk heterojunction (BHJ) organic solar cells prepared by blending a semiconductor donor (D) with an acceptor (A) polymer have achieved significant progress with power conversion efficiencies (PCEs) over 10% in the last decade. To achieve high PCEs, ensuring efficient charge transfer through the D/A interfaces becomes a critical process. Here, we utilize an alternative P–i–N structure of PBDB-T (D) blended with N2200 (A) as a photoactive layer fabricated by the sequential deposition method. In contrast with the BHJ, the P–i–N structure has advantages of controllable interfacial morphology favoring charge transfer and subsequent carrier transport. We have performed transient absorption spectroscopy (TAS) to study the distinctions of charge generation between these two structures. Based on TAS, the hole transfer efficiency is determined to be ∼62% for the ∼110 nm-thick P–i–N film, notably higher than ∼49% in the BHJ with ∼100 nm thickness. Analysis of thickness-dependent TAS of BHJ and P–i–N blend films further demonstrates the superiority of the P–i–N structure in terms of hole transfer and charge generation below a N2200 layer thickness of ∼75 nm. Our work shows that applying the P–i–N structure as the active layer is a promising way in promoting the performance of all polymer photovoltaic cells.

As the greatest medical and socioeconomic problem in developing countries, stroke is the second or third leading cause of death in China and worldwide. In adult organisms suffering from stroke, transplanted stem cells have the ability to repair damaged tissues by regenerating autologous cells, while ginsenoside Rg1 could promote proliferation and differentiation of stem cells. Although obvious antistroke effects of ginsenoside Rg1 and transplanted stem cells have been verified in publications, the mechanism exploration remains challenging. Our study was carried out to investigate the synergistic effects of ginsenoside Rg1 and neural stem cell (NSC) transplantation on MCAO rats with a 1H NMR-based nontargeted metabolomics method to identify potential biomarkers and protein targets and discover the potential mechanism. NSCs transplantation after MCAO combined with ginsenoside Rg1 administration could significantly improve the cerebral infarct and neurological deficits. The treatment significantly intervened the levels of ten metabolites, and perturbed energy metabolism, amino acids metabolism, and lipids metabolism. And 11 enzymes were identified and verified as the targets of NSCs transplantation and ginsenoside Rg1 administration on MCAO rats. Our findings helped to improve the antistroke mechanism of NSCs transplantation and ginsenoside Rg1 and supply a theory basis for the combined research of stem cells and Chinese medicine in the future.

The realization of high-Qsingle-mode lasing on the microscale is significant for the advancement of on-chip integrated light sources. It remains a challenging trade-off between Q-factor enhancement and light-field localization to raise the lasing emission rate. Here, we fabricated a zero-dimensional perovskite microcavity integrated with a nondamage pressed microlens to three-dimensionally tailor the intracavity light field and demonstrated linearly and nonlinearly (two-photon) pumped lasing by this microfocusing configuration. Notably, the microlensing microcavity experimentally achieves a high Q-factor (16700), high polarization (99.6%), and high Purcell factor (11.40) single-mode lasing under high-repetition pulse pumping. Three-dimensional light-field confinement formed by the microlens and plate microcavity simultaneously reduces the mode volume (∼3.66 μm3) and suppresses diffraction and transverse walk-off loss, which induces discretization on energy-momentum dispersions and spatial electromagnetic-field distributions. The Qfactor and Purcell factor of our lasing come out on top among most of the reported perovskite microcavities, paving a promising avenue toward further studying electrically driven on-chip microlasers.

All-polymer solar cells composed of wide-band-gap polymer poly(1-{4,8-bis[5-(2-ethylhexyl)thiophen-2-yl]-benzo[1,2-b:4,5-b′]dithiophen-2-yl}-3-methyl-5-(4-octylphenyl)-4H-thieno[3,4-c]pyrrole-4,6(5H)-dione) (PTP8) as the donor and poly[1,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)] [P(NDI2OD-T2), also known as Activink N2200] as the acceptor exhibit a broad absorbance in the range 300–900 nm, thanks to complementary absorption of near-infrared light by N2200. Although N2200 shows reasonably high electron mobility, the contribution of the photogenerated excitons in N2200 to the power conversion of the PTP8/N2200 solar cell is insignificant. Here, the hole transfer from N2200 to PTP8 in PTP8/N2200 blend films was investigated by utilizing ultrafast transient absorption spectroscopy. The spectral fingerprints of ground-state bleaching and hole polaron-induced absorption of PTP8 are identified under selective excitation of the N2200 component and unambiguously indicate hole transfer from N2200 to PTP8. The hole transfer is slow (∼100 ps), comparable to the geminate exciton recombination rate, consequently limiting the transfer efficiency and carrier generation. The hole-transfer efficiency depends on the PTP8/N2200 weight ratio, showing a highest value of ∼14.1% in the 3:2 film.

The Wide Field Survey Telescope (WFST) is a dedicated photometric surveying facility being built jointly by University of Science and Technology of China (USTC) and the Purple Mountain Observatory (PMO). It is equipped with a 2.5-meter diameter primary mirror, an active optics system, and a mosaic CCD camera with 0.73 gigapixels on the primary focal plane for high-quality image capture over a 6.5-square-degree field of view. The installation of WFST near the summit of Saishiteng mountain in the Lenghu region is scheduled in summer of 2023, and the operation is planned to start three months later. WFST will scan the northern sky in four optical bands (u, g, rand i) at cadences from hourly/daily in the deep high-cadence survey (DHS) program, to semi-weekly in the wide field survey (WFS) program. During a photometric night, a nominal 30 s exposure in the WFS program will reach a depth of 22.27, 23.32, 22.84, and 22.31 (AB magnitudes) in these four bands, respectively, allowing for the detection of a tremendous amount of transients in the low-zuniverse and a systematic investigation of the variability of Galactic and extragalactic objects. In the DHS program, intranight 90 s exposures as deep as 23 (u) and 24 mag (g), in combination with target of opportunity follow-ups, will provide a unique opportunity to explore energetic transients in demand for high sensitivities, including the electromagnetic counterparts of gravitational wave events, supernovae within a few hours of their explosions, tidal disruption events and fast, luminous optical transients even beyond redshift of unity. In addition, the final 6-year co-added images, anticipated to reach g≃ 25.8 mag in WFS or 1.5 mags deeper in DHS, will be of fundamental importance to general Galactic and extragalactic science. The highly uniform legacy surveys of WFST will serve as an indispensable complement to those of the Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST) that monitors the southern sky.

Fracture healing is a complex physiological process in which angiogenesis plays an essential role. Microfibril-associated glycoprotein-2 (MAGP2) has been reported to possess a proangiogenic activity via integrin αvβ3, yet its role in bone repair is unexplored. In this study, a critical-sized femoral defect (2 mm) was created in mice, followed by the delivery of an adenovirus-based MAGP2 overexpression vector or its negative control at the fracture site. At days 7, 14, 21, and 28 postfracture, bone fracture healing was evaluated by radiography, micro-computed tomography, and histopathologic analysis. Adenovirus-based MAGP2 overexpression vector–treated mice exhibited increased bone mineral density and bone volume fraction. MAGP2 overexpression contributed to an advanced stage of endochondral ossification and induced cartilage callus into the bony callus. Further analysis indicated that MAGP2 was associated with enhanced angiogenesis, as evidenced by marked MAGP2 and integrin αvβ3 costaining and increased endothelial cell markers such as endomucin and CD31 levls, as well as elevated phosphorylation of protein tyrosine kinase 2 (PTK2) and AKT serine/threonine kinase 1 (AKT) in the callus. In vitro, recombinant human MAGP2 treatment enhanced the viability, migration, and tube formation ability of human microvascular endothelial cells, which was partially reversed by integrin αvβ3 inhibition or MK-2206, a specific AKT inhibitor. Inhibition of integrin αvβ3 abolished MAGP2-induced PTK2 and AKT activation. Taken together, our data provide the first evidence that MAGP2 promotes angiogenesis and bone formation by activating the integrin αvβ3/PTK2/AKT signaling pathway.

In the current research field of non-fullerene solar cells, the device performance of all polymer solar cells (all-PSCs) lags significantly behind those based on polymer donor and molecule acceptor. To further improve the device performance of all-PSCs, the small molecule electron acceptor ITIC was introduced for the first time to the all-PSCs based on PTP8/P(NDI2HD-T). The combinative polymer/molecule acceptor P(NDI2HD-T)/ITIC with only a small amount of ITIC, 15wt% in acceptors and 6wt% in total, can significantly improve the device PCE from 6% to over 7%, which is among the highest-efficiencies for reported all-PSCs. The improved device performance can be attributed to the broadened absorption and optimized blend morphology, which can further enhance charge carrier generation and balance charge carrier mobility in the ternary blend. More importantly, we discovered that this strategy can be successfully applied to all-PSCs based on other polymer donors like widely spread P3HT or PTB7. Therefore, our work not only reveals the detailed effect of polymer-small molecule acceptor alloy in all-PSCs, but also suggest that the ternary cell strategy of polymer donor/polymer:molecule acceptor may become a general and facile approach to further boost the performance of current all-PSCs.

Current all polymer solar cells still suffer from low fill factors (FF) and short-circuit current density (Jsc) compared with the conventional polymer/fullerene system. Herein in this work, devices using PTP8 as the electron donor and [70]PCBM as well as widely used polymer N2200 as the electron acceptor were systematically studied and compared. The major loss mechanisms in the all polymer solar cells were investigated to understand their relatively lower performance than the PTP8/fullerene system. By performing in-depth analysis on ultrafast transient transmission spectroscopy results, we estimated that in PTP8/N2200 device nearly half of the charges recombine geminately, which is confirmed as the major factor hindering the device performance of all polymer solar cells compared with polymer/fullerene system. Through thorough morphology analysis, the low charge generation efficiency is attributed to the reduced crystallinity of N2200 in the blend film and the unfavorable face-to-edge orientation at the donor/acceptor heterojunction. Coupling these results with knowledge from efficient polymer/fullerene systems, the future design of new polymers can devote to increase the attraction between the π face of donor and acceptor, leading to enhanced face-to-face orientation at the heterojunction, while maintaining a high π-π stacking order for each polymer.

Ultrafast transient absorption (TA) spectroscopy was employed to investigate the thermal annealing effect on the charge transfer (CT) in bulk heterojunction (BHJ) all-polymer solar cells (all-PSCs) utilizing an n-type polymer P(NDI2OD-T2) (Polyera, N2200) as acceptor and a low bandgap polymer PBPT as donor. The CT generates hole polarons residing in the PBPT and electron polarons belonging to N2200, manifested in the TA spectra of the BHJ films as the long-lived absorption peak centered at ∼850 nm. The CT is most efficient in the film annealed at 160 °C and its efficiency declines monotonically when enhancing or reducing the annealing temperature, displaying a positive correlation with the power conversion efficiency (PCE) of the corresponding solar cell devices. This correlation is analyzed in terms of the crystallinity and phase separation, which are the key factors determining the performance of all-PSCs. Our results can provide valuable guidance for the fabrication of BHJ all-PSCs to improve their PCE.

To fabricate continuous carbon fiber (CF)/polyamide (PA 6) thermoplastic composites with high strength and stiffness, combinational treatments of liquid phase oxidation, coupling agent, and coating were adopted to improve the surface activity of CF fabric and interfacial bonding with PA 6 matrix. The mechanical properties, dynamic thermomechanical properties, microstructure, and hydrothermal aging behavior of the CF/PA 6 composites were studied. The XPS results showed the N, O, and Si elements as well as the C–O, CO, and C–Si groups were significantly increased on the CF surface, indicating the improvement of chemical activity and KH550 effectively grafted. The tensile strength significantly increased from 396 MPa to 480 MPa, by 21.2%, and Young's modulus increased from 38.6 GPa to 47.9 GPa, by 24.1%, respectively. The result of the damp heat aging test in 240 h showed the retention rate of flexural strength and ILSS were 66% and 67%, respectively.

Femtosecond laser has offered a precise, controllable, and environmentally friendly solution for manufacturing superhydrophobic surfaces adorned with micro and nanostructures. It has shown great application value in self-cleaning, anti-icing, drag reduction, droplet manipulation, water/fog harvesting, corrosion resistance, wear resistance, oil-water separation, and antibacterial functionality. In light of these advancements, this paper aims to provide a comprehensive review and insightful discussion regarding the development of fs laser-processed superhydrophobic surfaces, encompassing surface microstructure and chemistry states. In terms of microstructure, the review explores remarkable superhydrophobic properties associated with LIPSS, microgroove hierarchical structures, microcolumn/microcone hierarchical structures, micro pits/holes hierarchical structures, and other random nanostructures. These distinctive surface architectures have illustrated notable capabilities in achieving superhydrophobicity. Furthermore, the analysis delves into the realm of surface chemical states, offering detailed insights into the utilization of fs laser technology as a means to attain surface superhydrophobic functionality. Alongside this, the paper presents a comprehensive summary of research progress pertaining to the efficient replication of polymer superhydrophobic surfaces embedded with micro and nanostructures. This review will facilitate enhanced comprehension and foster a deeper appreciation of the interplay between fs laser processing technology and wettability.

Blue-emission (∼480 nm) CsPbBr3nanoparticles with ultra-small size (∼2.1 nm) are synthesized using the liquid nitrogen freezing with the ligand of dodecylbenzene sulfonic acid (DBSA). Asymmetric narrow emissions at the low energy side, with the full width at half-maximum of ∼20 nm, are observed in solution and film at room temperature. The spectral asymmetry is mainly ascribed to phonon vibronic replica with averaged phonon energy of ∼40 meV. Moreover, exciting this CsPbBr3nanoparticles solution using linearly polarized 6 ns pulsed laser at 355 nm, we observe polarized emission with polarization degree (PPL) of ∼7%, and PPLdecreases more than 20% in the vibronic progression. However, the PPLgoes to zero in frozen solutions as well as in films. Thus we speculate the polarized emission is due to the photoinduced re-alignment of nanoparticles, and the diminished PPLat the phonon side band may be due to the non-adiabatic electronic-to-vibronic transitions. The novel phenomena from the ultra-small CsPbBr3nanoparticle demonstrated in this work may provide fundamental insights into its photophysics with direct implications for optoelectronics.

To reveal the complexities of microstructures at the Al/Ti interface, Al/Ti/Al sandwich structures are produced through thermal pressing and annealing treatment. The multi-scale interface structures, elemental diffusion, grain characteristics, and micromechanics are explored by scanning electron microscopy (SEM), electron back-scattered diffraction (EBSD), transmission electron microscopy (TEM), and nano-indentation. The results indicate only TiAl3is generated at the interface, and the interlayer thickness and TiAl3grain size increase with rising temperature. On the microscale, a compact interlayer is visible at 500 and 550 °C, whereas massive Al-enriched bulks are dispersed in the interlayer as the temperature increases to 650 °C. Abnormal micro-defects at 600 and 650 °C are partially formed with the thickening of the interlayer and the segregation of Mg and Si. Unexpectedly, interfacial microvoids, amorphous layers, and oxides are detected, which hinder the growth of the interlayer. On the nanoscale, misfit dislocations and lattice distortions are noticed at the interface. More interestingly, the Ti–Al solid solution structures with severe lattice misfits are generated on the three-dimensional (3D) Ti/TiAl3interface, which is considered to be a novel strategy for enhancing the strength-plasticity synergy of composite structures.

With the rapid development of multiple sensors for shape acquisition and inspection, point-based discrete shape modeling is being widely used in many engineering applications, e.g. reverse engineering, quality control, etc. Geometry processing, which aims at recovering information about topology, geometry and shape from the measured data is one of the critical issues to achieve multiple sensors integration in coordinate metrology. This paper presents a novel approach for discrete geometry processing in multisensor coordinate metrology. Two important issues are addressed here: registration and segmentation. We propose here a new modified Iterative Closest Point (ICP) algorithm to improve the registration performances by using the curvature information. Shape recognition and segmentation are the most critical issues of discrete geometry processing. The local surface types and the characteristic points are first recognized based on two surface descriptors: shape index and curvedness. A clustering method is developed to classify the vertices according to their surface types, and a connected region generation approach is developed for final segmentation. Finally, an industrial case study is presented to illustrate the entire approach, and to demonstrate the validity of the proposed methods for engineering applications.

Abstract: The CCD photometric observation of comet 103P/Hartley 2 with broadband optical filters was carried out at Xuyi Station of Purple Mountain Observatory, Chinese Academy of Sciences by use of Near Earth Object Telescope (NEOT). We monitored the comet from September 30 to November 4, 2010 and investigated the variation of activities. The Afρ parameter derived from our r broadband data varies from 46.0 to 126.0 cm and increases with time. The dust production rate in terms of Afρ was measured and a tentative calculation of the dust (or gas) loss-rate of nucleus was executed under the assumption that the nucleus of comet 103P/Hartley 2 is spherical. The r-band image and the surface brightness profile taken on September 30, 2010 was measured and the gradient of surface brightness profile of 103P/Hartley 2 showed m < −1.5.

The high molecular weight glutenin subunits (HMW-GS) 7+8 were introduced into the Long 97-586 (1, 7, 2+12) wheat variety (Triticum aestivum)by 5 consecutive backcrosses with biochemical marker-assisted selection. Nearly isogenic lines (NILs) of HMW-GS 7 and 7+8 were obtained, and the NILs were planted in the experimental field at the Crop Breeding Institute of Heilongjiang Academy of Agricultural Science in 2004–2006. The field experiments were designed using the two-column contrast arrangement method with six replicates in 2004–2005 and four replicates in 2006. The result of three years experiments showed that the differences between NILs of Long 97–586 with subunit 7 and those with subunits 7+8 in the quality parameters of flour protein content and dry gluten content were negligible (P>0.1). However, the differences in some of the quality parameters were remarkably significant (P<0.01), including wet gluten content, ratio of wet gluten/dry gluten, gluten index, Zeleny sedimentation, ratio of sedimentation/dry gluten, and the farinogram parameters of water absorption, development time, stability, breakdown time and degree of softening. The difference between NILs with subunits 7+8 and subunit 7 was significant (P<0.05) on the alveogram W value and had a critical value (P=0.05) on the alveogram P value in 2006. The results show that HMW-GS 7+8 is far superior to HMW-GS 7 in terms of baking quality. The possibilities of using subunits 7+8 and subunit 7 in breeding strong and weak gluten wheat varieties are discussed in this paper.

Abstract: Based on large quantities of co-orbital phenomena in the motion of natural bodies and spacecraft, a model of the co-orbital restricted three-body problem is put forward. The fundamental results for the planar co-orbital circular restricted three-body problem are given, which include the selection of variables and equations of motion, a set of approximation formulas, and an approximate semi-analytical solution. They are applied to the motion of the barycenter of the planned gravitational observatory LISA constellation, which agrees very well with the solution of precise numerical integration.

The Boston Keratoprosthesis type I (B-KPro) is widely used in the world, but the lack of donor corneas limits its application. This study aims to prepare the acellular porcine cornea (APC) crosslinked with ultraviolet A (UVA)/riboflavin instead of donor corneas as the scaffold for B-KPro. Decellularization of freeze-thaw combined with biological enzymes resulted in approximately 5 ng/mg DNA residue, the a-Gal removal rate of 99%, and glycosaminoglycans retention at a high level of 46.66 ± 2.59 mg/mg. UVA/ riboflavin cross-linking was adopted to induce the formation of new chemical bonds between adjacent collagen chains in the corneal stroma to improve the mechanical properties and resistance to enzymatic hydrolysis. Through comprehensive analysis of the biomechanics, enzyme degradation, immunogenicity and histological structure of the APC crosslinked at different times, CL3 (irradiation conditions, 365 nm, 3 mW/cm, 80 min, both sides) was selected and transplanted into the rabbit cornea model through interlamellar keratoplasty and penetrating keratoplasty as the scaffold of the B-KPro. Compared with the native porcine cornea (NPC) and APC, the experiment of interlamellar pocket indicated that the structure of CL3 was homogeneous without degradation and vascularization in vivo at 12 weeks after surgery. Simultaneously, the results of transplantation of B-KPro showed complete epithelialization of CL3 within 1 week, and neovascularization of the cornea indicated rejection but could be controlled with immunosuppressants. At 3 months postoperatively, the lens of B-KPro remained transparent, and the structure of CL3 was compact and uniform, accompanied by the migration and proliferation of a large number of stromal cells without degradation, suggesting the CL3 could be a promising corneal substitute.

On the basis of the radar observational data of the Leonids obtained in China in November of 1998, we found that the characteristics of the meteor population index γ during the main peak could not be explained well with a one-component magnitude distribution. Moreover, according the visual observational data obtained in China and other districts of Asia, γ also presents the property of non-uniformity. In this paper, we set forth a mathematical model of mixed particle streams. From this, the observed phenomenon of rarity of visual meteors and abundance of radar meteors during the main peak is interpreted.

Abstract—Seventy‐five orbits of Leonid meteors obtained during the 1998 outburst are presented. Thirty‐eight are precise enough to recognize significant dispersion in orbital elements. Results from the nights of 1998 November 16/17 and 17/18 differ, in agreement with the dominant presence of different dust components. The shower rate profile of 1998 November 16/17 was dominated by a broad component, rich in bright meteors. The radiant distribution is compact. The semimajor axis is confined to values close to that of the parent comet, whereas the distribution of inclination has a central condensation in a narrow range. On the other hand, 1998 November 17/18 was dominated by dust responsible for a more narrow secondary peak in the flux curve. The declination of the radiant and the inclination of the orbit are more widely dispersed. The argument of perihelion, inclination, and the perihelion distance are displaced. These data substantiate the hypothesis that trapping in orbital resonances is important for the dynamical evolution of the broad component.

Pronounced spin precessions are observed in Fe films grown on n-doped GaAs(001) with a tailored Schottky interface under low-energy ultrafast laser excitation, more than two orders of magnitude smaller than typically required in heat-induced excitation. Pump wavelength dependence of the precession amplitude shows that the fast drift of the optically excited free carriers in the narrow depletion layer of GaAs is the key mechanism to generate the significant transient magnetic field triggering spin precessions.

The purpose of this study was to evaluate the shear bond strength of a self-etch adhesive to caries-affected dentin after caries removal by erbium: yttrium, aluminum garnet (Er:YAG) laser and analyze the resin-dentin interface. The caries-infected dentin of human molars were removed by Er:YAG laser with energy density of 20 J/cm2and pulse repetition rate of 20 Hz. The conventional bur was used as control group. After bonding procedures, specimens were subjected to shear bond strength test and the adhesive interface was examined by laser confocal scanning microscope (LCSM). The result showed that Er:YAG laser could effectively remove dentin caries. There was no statistical difference in shear bond strength between two groups and the adhesive interface created on laser-irradiated dentin surface presented similar feature to that on bur-ground surface.