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For a long time, seasonal drought occurs frequently in Southwest China, and the management of water and fertilizer in kiwifruit orchards has no quantitative standards, which seriously affects the yield and quality of kiwifruit. Therefore, the effects of water and fertilizer deficit regulation with drip irrigation (WFDRDI) on the quality of kiwifruit at different growth stages were explored to achieve water and fertilizer saving, and green and efficient production of kiwifruit. We select ‘Jin Yan’ kiwifruit and set two water deficit levels (WD20%and WD40%) and three fertilizer deficit levels (FD15%, FD30%and FD45%) at bud burst to leafing stage (stage I), flowering to fruit set stage (stage II), fruit expansion stage (stage III) and fruit maturation stage (stage IV), respectively, with a full irrigation and fertilization as the control treatment (CK) in 2017 and 2018. Results showed that the WFDRDIat stage II and III had significant effect on fruit physical quality of kiwifruit, specifically, the III-WD40%FD30%and III-WD20%FD45%treatments significantly increased fruit firmness by 13.62 and 15.59% (P<0.05), respectively; the II-WD40%FD15%and III-WD40%FD15%treatments significantly increased dry matter by 8.19 and 6.47% (P<0.05), respectively; the III-WD20%FD15%treatment significantly increased single fruit weight and fruit volume by 9.33 and 12.65% (P<0.05), respectively; the II-WD20%FD15%treatment significantly increased fruit water content by 1.99% (P<0.05). The WFDRDIhad an obvious effect on fruit chemical quality of kiwifruit. The III-WD20%FD45%, IV-WD40%FD15%and IV-WD20%FD30%treatments significantly increased vitamin C (Vc) content by 69.96, 36.96 and 34.31% (P<0.05), respectively; the III-WD40%FD15%and IV-WD40%FD15%treatments significantly increased total soluble solid (TSS) content by 3.79 and 17.05% (P<0.05), respectively, and significantly increased soluble sugar content by 28.61 and 34.79% (P<0.05), respectively; the contents of fructose, glucose and sucrose also had a significantly increasing trend, which was increased significantly by 5.58–19.63%, 40.55–60.36% and 54.03–54.92% in the III-WD40%FD15%and IV-WD40%FD15%treatments (P<0.05), respectively; sugar–acid ratio was increased significantly in the IV-WD40%FD15%treatment by 64.65% (P<0.05). The degree and duration of water and fertilizer deficit had a comprehensive effect on fruit quality of kiwifruit. The WFDRDIat stage II and III contribute to improving fruit physical quality, and the threshold of water and fertilizer deficit were 20 and 15%, respectively; stage III and IV are the critical periods for improving fruit chemical quality by water and fertilizer coupling effect, and the threshold of water and fertilizer deficit were 40 and 15%, respectively. Therefore, aiming at precise water and fertilizer saving, the I-WD20%FD30%, II-WD40%FD15%, III-WD40%FD15%and IV-WD40%FD15%treatments under WFDRDIduring the whole growth period of kiwifruit were the best mode to improve quality and production of kiwifruit.

The root of Paris polyphyllavar. yunnanensis, a famous and endangered traditional Chinese herb, has a significant medicinal value. The aim of this study was to analyze the composition and functional characteristics of bacterial endophytes in roots, stems, and leaves of P. polyphyllavar. yunnanensis. The 16S rRNA gene sequencing and functional prediction of bacterial endophytes in roots, stems, and leaves of P. polyphyllavar. yunnanensiswere conducted. The Chao and Shannon indices of the bacteria in roots were significantly higher than those in stems and leaves. The dominant endophyte phyla were Cyanobacteria, Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. The main genera detected in roots were unclassified Cyanobacteria, Rhizobium, Flavobacterium, and Sphingobium; the main genera in stems were norank_c__Cyanobacteria, Bacillus, and Pseudomonas; the main genera in leaves were norank_c__Cyanobacteriaand Rhizobium. The microbiota in roots was particularly enriched in functional categories “extracellular structures” and “cytoskeleton” compared with stems and leaves (p< 0.05). Our study reveals the structural and functional characteristics of the endophytic bacteria in roots, stems, and leaves of P. polyphyllavar. yunnanensis, which aids in the scientific understanding of this plant.

Aiming at the ever-changing assembly error along with operation in the large scale assembly space, the diversity of machine tool assembly error migration and its operation route are characterised by making use of the correspondence relationship between joint surface error and operation distance. The formation and retention of assembly error are respectively revealed by the forward migration and the reverse migration of assembly error. Furthermore, the delayed step function of assembly error migration is constructed to recognise the potential control operation of error migration. Based on the response surface method, the solution model of assembly error migration is established to reveal the diversity of assembly error migration process and the effect of multiple operations. Finally, the design method of assembly process about heavy duty machine tool is proposed, and its effectiveness is verified by gantry-moving type turning-milling machining centre.

The objective of this study was to assess the feasibility of percutaneous balloon pulmonary valvuloplasty (PBPV) under echocardiographic guidance only. PBPV has become the preferred choice for pulmonary valve stenosis (PS). We report the first‐in‐human successful PBPV under only echocardiography guidance for isolated PS. From March 2013 to December 2014, 34 patients with congenital PS underwent PBPV with echocardiography as the only imaging modality in the ordinary operation room or catheter lab. Outpatient follow‐up including chest radiography, electrocardiography, and transthoracic echocardiography (TTE) was conducted at 1, 3, 6, and 12 months. All 34 patients successfully underwent PBPV under echocardiography guidance without radiation and contrast agent. The pulmonic transvalvular pressure gradient dropped from 62.8 ± 10.1 mm Hg to 14.7 ± 4.2 mm Hg measured on catheterization (P< .05). The balloon diameter/pulmonary annulus diameter ratio was 1.34 ± 0.07. Slight regurgitation of the pulmonary valve occurred in five patients and mild pulmonary regurgitation occurred in one patients. The pulmonic transvalvular pressure gradient measured on TTE 12 months after the procedure was 14.1 ± 4.6 mm Hg. No pericardial effusion and peripheral vascular complications occurred. This study demonstrated that PBPV can be successfully performed under only echocardiography guidance and appears safe and effective while avoiding radiation and contrast agent use.

We report on blue phosphorescent organic light-emitting diodes (PHOLEDs) with biphenyl (Spiro [fluorene-9,9′-xanthen]-2-yl) phosphine oxide (SFX2PO) host. The device studied in this work has the structure of ITO/m-MTDATA:MoOx3:1(8nm)/m-MTDATA(32nm)/ TAPC(10nm)/SFX2PO: Firpic (10nm)/Bphen (40nm)/LiF(1nm)/Al (200nm). Maximum luminance of 9120 cd/m2 and power efficiency of 16.84 lm/w have been achieved in this device.

The existing safety evaluation of high-speed milling cutter mainly based on ISO15641 standards, which by idling experiments, then analysis and determine centrifugal force conditions what cause permanent deformation and fracture destructive of cutter, this method cannot be forecast and control the dynamic evolution of the milling cutter's safety and reliability, when cutting load changed suddenly.This paper using the high speed milling cutter's failure criteria and safety margin model of cutting hardened steel, analysed and evaluated coupled thermal field distribution caused by hardened steel surface feature that changed frequently and cutter's impact, fatigue, strength, stiffness, safety margin which cuased by mutated shock load of cutter, then forecast safety and reliability of high-speed milling cutter, and proposed the control method of safety and reliability that could milled hardened steel in high speed.

Focus on the problems that heavy duty machine tool lack of fault samples and process information in repetitive assembly, result in the existing assembly process method can’t meet the repetitive assembly accuracy. According to characteristics of local machine assembly process, propose its assembly repeatability evaluation indexes. Establish the mapping relation among machine performance, assembly accuracy and structure, and built a hierarchical model of assembly process, obtain the process optimal design scheme of assembly accuracy repeatability. Use the multivariate function differential method, propose a calculation method of heavy machine assembly accuracy, and verify applicability of the method, depend on the machine loads and structure criterions, propose heavy machine assembly accuracy repeatability optimization method, example analysis shows that: the servo effect of repetitive assembly accuracy in new process is obvious, simultaneously stress field magnitude and stability of new technology is better than the original, realize effective control of the machine tool assembly accuracy repeatability.

Existing research on machined surface topography, only consider its response to vibration or wear certain factors, both vibration and wear impact on machined surface topography exist ambiguity and uncertainty, it cannot solve the design conflicts of machined surface topography. For this, this paper analyzes blade installation error, tool wear, vibration and deformation to reveal effects of tip space trajectory, build a three-dimensional model of machined surface topography in simulation, extract its characteristic parameters, by simulation of different amplitudes and wear, found that axis amplitude is a key factor affecting surface residual height, flank wear affects contour distribution distance significantly, by specimen milling experiments, use vibration measuring instrument and ultra-depth microscopy to obtain vibration, wear characteristics and machined surface topography parameters under different cutting parameters, then use the gray system theory to get correlation analysis of the test data, results showed that the influence of tool wear on machined surface topography is prominent than tool vibration.

The influence of non-coaxial constitutive model on predictions of dense sand behavior is investigated in this paper. The non-coaxial model with strain softening plasticity is applied into finite-element program ABAQUS, which is first used to predict the stress-strain behavior and the non-coaxial characteristic between the orientations of the principal stress and principal plastic strain rate in simple shear tests. The model is also used to predict load settlement responses and bearing capacity factors of shallow foundations. A series of centrifuge tests for shallow foundations on saturated dense sand are performed under drained conditions and the test results are compared with the corresponding numerical results. Various footing dimensions, depths of embedment, and footing shapes are considered in these tests. In view of the load settlement relationships, the stiffness of the load-displacement curves is significantly affected by the non-coaxial model compared with those predicted by the coaxial model, and a lower value of non-coaxial modulus gives a softer response. Considering the soil behavior at failure, the coaxial model predictions of bearing capacity factors are more advanced than those of centrifuge test results and the non-coaxial model results; besides, the non-coaxial model gives better predictions. The non-coaxial model predictions are closer to those of the centrifuge results when a proper non-coaxial plastic modulus is chosen.

The steering radius and the vehicle velocity is utilized to control the drive force and steering angle of each electric-wheel in this essay. In order to improve the characteristics of vehicle, a dynamic simulation was made with the predictions of constant velocity and radius to the vehicle model with the R-v control strategy. This simulation proves that the characteristics of vehicle steering will be better with the utilization of this control strategy.

5,7,12,14-Tetrachloro-6,13-diaza-6,13-dihydropentacene (TCDAHP) and 5,7,12,14-tetrachloro-6,13-diazapentacene (TCDAP) were synthesized and assessed as the active channel materials for thin-film transistor applications. Analyses of the crystal structures of these molecules revealed that both exhibited slipped π−π stacking of the long and fused aromatic moiety. Although the packing features of the two compounds are basically identical, their highest occupied molecular orbitals, which are relevant to hole transport, are very different. Better mobility was predicted for TCDAHP over TCDAP based on the dimeric structure in the X-ray coordinates. The morphologies of thin films of TCDAHP and TCDAP prepared by thermal evaporation depend critically on the substrate on which the molecules were deposited: from the amorphous state on a SiO2/Si surface to the crystalline state on a pentacene buffer layer surface. The performance of thin-film transistors prepared on various substrate surfaces was studied. While no field-effect mobility was observed for these films deposited on SiO2/Si, a high mobility of 1.4 cm2/(V s) for the TCDAHP film was achieved when deposited on a pentacene buffer layer prepared on a rubbed monolayer of n-nonyltrichlorosilane on a SiO2/Si surface. A similar device prepared from TCDAP gave a mobility of 0.13 cm2/(V s).

The synthesis as well as crystal and molecular structure of [Bi(C5H4NOS)3] are reported. The complex crystallizes in the monoclinic system, space group P21/nwith lattice parameters a= 9.6521(3) Å, b= 10.0659(4) Å, c= 18.4484(7) Å, β = 102.13(6)°, and Dcalc= 2.227 Mg · m−3for Z= 4. It is clear from the packing diagram that the title compound is a dimer via the secondary coordination. Surrounding Bi atom, three five-membered ring planes (Bi,O,N,C,S) make a dihedral angle of 55.91, 54.72, and 26.13° respectively. The whole crystal presents a three-dimensional network structure as each molecule produces four weak C–H ⋅ ⋅ ⋅ O hydrogen bonds and a weak C–H ⋅ ⋅ ⋅ S hydrogen bond.

An integrated optoelectronic device is demonstrated with a high–mobility conjugated oligoaniline field-effect transistor (FET) driving a poly(2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene)vinylene (MEH-PPV) light-emitting diode (LED). The FET fabricated with oligoaniline (16-mer) thin film as the semiconductor layer exhibits ideal source current–drain-source voltage characteristics. Its performance is close to those of inorganic amorphous silicon FETs, with field-effect mobilities of 0.1–1.0 cm²/V s and on–off current ratio of 10⁶. The FET-LED integrated device exhibits a current of 8 × 10⁻⁴ A with the maximum brightness on the order of 10 cd/m² at gate voltage of −100 V and drain-source voltage of 60 V. Copyright © 2003 John Wiley & Sons, Ltd.

An integrated optoelectronic device is demonstrated with a high–mobility conjugated oligoaniline field‐effect transistor (FET) driving a poly(2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylene)vinylene (MEH‐PPV) light‐emitting diode (LED). The FET fabricated with oligoaniline (16‐mer) thin film as the semiconductor layer exhibits ideal source current–drain‐source voltage characteristics. Its performance is close to those of inorganic amorphous silicon FETs, with field‐effect mobilities of 0.1–1.0 cm2/V s and on–off current ratio of 106. The FET‐LED integrated device exhibits a current of 8 × 10−4A with the maximum brightness on the order of 10 cd/m2at gate voltage of −100 V and drain‐source voltage of 60 V. Copyright © 2003 John Wiley & Sons, Ltd.

These field‐effect transistors (FETs) are fabricated with 16ANI (16‐mer aniline oligomer) thin films as the semiconducting layer. These FETs have ideal source current–drain source voltage characteristics. The field‐effect mobility (fabricated by vacuum evaporation) is 0.034 cm2/V sec and on/off current ratio above 104, which are two orders of magnitude larger than those fabricated by spin‐coating technique. These transistor's performances can be improved significantly for FET fabrication by vacuum evaporation. Copyright © 2000 John Wiley & Sons, Ltd.

These field-effect transistors (FETs) are fabricated with 16ANI (16-mer aniline oligomer) thin films as the semiconducting layer. These FETs have ideal source current–drain source voltage characteristics. The field-effect mobility (fabricated by vacuum evaporation) is 0.034 cm²/V sec and on/off current ratio above 10⁴, which are two orders of magnitude larger than those fabricated by spin-coating technique. These transistor's performances can be improved significantly for FET fabrication by vacuum evaporation. Copyright © 2000 John Wiley & Sons, Ltd.

Endophytic microorganisms absorb nutrients and prevent pathogen damage, supporting healthy plant growth. However, the relationship between endophytic bacteria and berberine synthesis in the medicinal plant Coptis teetaWall. remains unclear. Herein, we explored the community composition of endophytic bacteria related to berberine in roots, stems, and leaves of wild-type and cultivated C. teeta. Endophytic bacterial communities were analyzed by 16S rRNA sequencing, and berberine content in roots was analyzed by high-performance liquid chromatography. Proteobacteria, Actinobacteria, and Bacteroidetes were the major phyla, and Mycobacterium, Salmonella, Nocardioides, Burkholderia-Paraburkholderia, and Rhizobiumwere the dominant genera in root, stem, and leaf tissues. Root berberine content was positively correlated with total N, total P, total K, and available K in rhizosphere soil. In addition, root berberine content was positively correlated with Microbacteriumand norank_f_7B-8, whereas soil total K was positively correlated with Microbacteriumand Burkholderia-Paraburkholderiain roots. Our results demonstrated a clear correlation between dominant endophytic bacteria and berberine synthesis in C. teeta. The findings are useful for the promotion of berberine production in C. teetavia manipulation of endophytic bacteria.