Genome-wide identification of the pectate lyase(PEL)gene family members in Malvaceae,and their contribution to cotton fiber quality

Pectin is a major constituent of the plant cell wall.Pectate lyase(PEL,EC 4.2.2.2)uses anti-β-elimination chemistry to cleave theα-1,4 glycosidic linkage in the homogalacturonan region of pectin.However,limited information is available on the comprehensive and evolutionary analysis of PELs in the Malvaceae.In this study,we identified 597PEL genes from 10 Malvaceae species.Phylogenetic and motif analyses revealed that these PELs are classified into six subfamilies:Clades I,II,III,IV,Va,and Vb.The two largest subfamilies,Clades I and II,contained 237 and222 PEL members,respectively.The members of Clades Va and Vb only contained four or five motifs,far fewer than the other subfamilies.Gene duplication analysis showed that segmental duplication played a crucial role in the expansion of the PEL gene family in Gossypium species.The PELs from Clades I,IV,Va,and Vb were expressed during the fiber elongation stage,but nearly all PEL genes from Clades II and III showed no expression in any of the investigated fiber developmental stages.We further performed single-gene haplotype association analysis in 2,001G.hirsutum accessions and 229 G.barbadense accessions.Interestingly,14 PELs were significantly associated with fiber length and strength traits in G.barbadense with superior fiber quality,while only eight GhPEL genes were found to be significantly associated with fiber quality traits in G.hirsutum.Our findings provide important information for further evolutionary and functional research on the PEL gene family members and their potential use for fiber quality improvement in cotton.

Atomic layer deposition in advanced display technologies:from photoluminescence to encapsulation

Driven by the growing demand for next-generation displays,the development of advanced luminescent materials with exceptional photoelectric properties is rapidly accelerating,with such materials including quantum dots and phosphors,etc.Nevertheless,the primary challenge preventing the practical application of these luminescent materials lies in meeting the required durability standards.Atomic layer deposition(ALD)has,therefore,been employed to stabilize luminescent materials,and as a result,flexible display devices have been fabricated through material modification,surface and interface engineering,encapsulation,cross-scale manufacturing,and simulations.In addition,the appropriate equipment has been developed for both spatial ALD and fluidized ALD to satisfy the low-cost,high-efficiency,and high-reliability manufacturing requirements.This strategic approach establishes the groundwork for the development of ultra-stable luminescent materials,highly efficient light-emitting diodes(LEDs),and thin-film packaging.Ultimately,this significantly enhances their potential applicability in LED illumination and backlighted displays,marking a notable advancement in the display industry.

In situ luminescence measurements of GaN/Al_(2)O_(3) film under different energy proton irradiations

Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within the material.The energies of H^(+)were set to 500 keV,640 keV and 2 MeV,the Bragg peaks of which correspond to the GaN film,GaN/Al_(2)O_(3) heterojunction and Al_(2)O_(3) substrate,respectively.A photoluminescence measurement at 250 K was also performed for comparison,during which only near band edge(NBE) and yellow band luminescence in the GaN film were observed.The evolution of the luminescence of the NBE and yellow band in the GaN film was discussed,and both exhibited a decrease with the fluence of H^(+).Additionally,the luminescence of F centers,induced by oxygen vacancies,and Cr^(3+),resulting from the ^(2)E →^(4)A_(2) radiative transition in Al_(2)O_(3),were measured using 2 MeV H^(+).The luminescence intensity of F centers increases gradually with the fluence of H^(+).The luminescence evolution of Cr^(3+)is consistent with a yellow band center,attributed to its weak intensity,and it is situated within the emission band of the yellow band in the GaN film.Our results show that IBIL measurement can effectively detect the luminescence behavior of multilayer films by adjusting the ion energy.Luminescence measurement can be excited by various techniques,but IBIL can satisfy in situ luminescence measurement,and multilayer structural materials of tens of micrometers can be measured through IBIL by adjusting the energy of the inducing ions.The evolution of defects at different layers with ion fluence can be obtained.

Effect of Lattice Mismatch on Luminescence of ZnO/Si Hetero-Structure

The photoluminescence （PL） and Raman spectra of undoped ZnO films deposited directly on Si substrate （sample A）,on Si substrate through a SiC buffer layer （sample B）,and on a ZnO crystal wafer （sample C） are investigated. There are emission peaks centered at 3.18eV （ultraviolet,UV） and 2.38eV （green） in these sampies. Comparing the Raman spectra and the variation of the PL peak intensities with annealing atmosphere, we conclude that the luminescence of the samples is related to the tensile strain in the ZnO film due to the lattice mismatch between the film and the substrate. In particular, the tensile strain reduces the formation energy of OZn antisite oxygen defects,which generate the green emission center. After annealing in oxygen-rich atmosphere, many OZn defects are generated. Thus, the intensity of green emission in ZnO/Si hetero-structure materials increases due to tensile strain in ZnO films.

Synthesis and upconversion luminescence of Lu_2O_3:Yb^(3+),Tm^(3+) nanocrystals

Lutetium oxide nanocrystals codoped with Tm3＋ and Yb3＋ were synthesized by the reverse-like co-precipitation method, using ammonium hydrogen carbonate as precipitant. Effects of the Tm3＋, Yb3＋ molar fractions and calcination temperature on the structural and upconversion luminescent properties of the Lu2O3 nanocrystals were investigated. The XRD results show that all the prepared nanocrystals can be readily indexed to pure cubic phase of Lu2O3 and indicate good crystallinity. The experimental results show that concentration quenching occurs when the mole fraction of Tm3＋ is above 0.2%. The optimal Tm3＋ and Yb3＋ doped molar fractions are 0.2% and 2%, respectively. The strong blue （490 nm） and the weak red （653 nm） emissions from the prepared nanocrystals were observed under 980 nm laser excitation, and attributed to the 1G4→3H6 and IG4→3F4 transitions of Tm3＋, respectively. Power-dependent study reveals that the 1G4 levels of Tm3＋ can be populated by three-step energy transfer process. The upconversion emission intensities of 490 nm and 653 nm increase gradually with the increase of calcination temperature. The enhancement of the upconversion luminescence is suggested to be the consequence of reducing number of OH- groups and the enlarged nanoerystal size.

麻类脱胶高效菌株DCE01的Pel325基因克隆与表达

采用软件Primer premier 5设计引物,从麻类脱胶高效菌株DCE01中克隆出一个果胶酶基因Pel325,重组到表达载体p ET-28a中,在E.coli BL21(DE3)中成功表达。试验结果显示,酶的活性随着底物(橘子果胶)酯化程度的增加而增加。胞内酶用酯化程度≥85%的橘子果胶作底物检测时酶活最高(酶活为37.5U/ml),其最适反应温度为55℃,最适反应p H为8.0。该结果可为进一步发掘DCE01菌株的基因资源提供重要科学依据。

麻类脱胶高效菌株DCE01的Pel4I8基因克隆与表达

从麻类脱胶高效菌株DCE01中克隆出一个果胶酶基因Pel4I8,采用表达载体p ET-28a,在E.coli BL21(DE3)中成功表达。实验结果表明,底物(橘子果胶)的酯化度对酶活有较大影响,用酯化程度在55%-70%的橘子果胶作底物时酶活最高(酶活为17.5U/ml);胞内酶最适反应温度为55℃,最适反应p H为9.5。该结果可为深入发掘DCE01菌株的基因资源提供重要科学依据。

Effects of Magnetic Stress on the Delayed Luminescence of Mung Bean Leaves

[Objective] The research aimed to study the effects of magnetic stress on the delayed luminescence of mung bean leaves.[Method]With mung bean leaves as the experimental materials,the delayed luminescence curve of mung bean leaves under the same magnetic field intensity at different processing time was measured by using BPCL-type weak luminescence measuring instrument.[Result] The absorption of the magnetic field stimulation within the leaves had its own rules.A certain magnetic field intensity and a certain...

基于PEL模型的管理制度评价思考

随着社会关系的变革速度的加快,管理制度创新成为一种趋势。对新的管理制度进行一定的评价是必要的。高奇在《科学方法实践》中提出的PEL模型,是提供所需要的预设、证据和逻辑去支持一个给定的科学结论的科学证明模型,也是对科学理论进行评价的模型。本文尝试将这一模型运用于管理评价中,分别从管理预设、管理中的制度以及管理论证中的逻辑三个方面对管理制度的科学性评价进行研究。

Preliminary Studies on High-performance Liquid Chro-matography Chemiluminescence Determination of theSaturated Fatty Acids(C_(16) C_(18))in Human Serum

The peroxyoxalate chemiluminescence(CL)detection of fatty acids in human se- rum combined with high-performance liquid chromatography (HPLC)is described.Some fatty acids in serum were extracted with a 1 :1(v/v)mixture of chloroform-n-heptane.2-(4-Hydrazinocarbonyl- phenyl)-4,5-diphenylimidazole (HCPI) was used as a fluorescent labelling reagent of the fatty acids. The labelling reaction was carried out at 30℃ for 1 h at pH 6.5 and the resulting reaction mixture was sudjected to HPLC. The labelled fatty acid C_(17)(P-C_(17))was used as the internal standard. The la- belled fatty acids C_(16) and C_(18) were separated within 18 min on an ODS-8OTM column (150 mm× 6 mm ID,5μm,Tosoh Japan).The calibrlation curves of fatty acids from the spiked control serum were Y_1=-0.003 7 + 0.0028X_1,r=0.994 for FA C_( 16) and Y_2=0.00 1 2 + 0.00098X_2,r=0.999 for FA C_( 18),respectively.The average recoveries of facids from the spiked contrl serum were 107.2%(n=8,RSD=4.3%)for FA C_(16) and 97.35%(n=8, RSD=4.0%)for FA C_(18),respectively.The lower detection limits of fatty acids after reaction were 12μmol per 20μl injection for FA C_(16) and 18 μmol per 20μl injection for FA C_(18),respectively(signal to noise ratio, S/N=2).The HPLC/CL method was applied to the determination of FA C_(16) and FA C_(18) in normal human serum and the results showed that the concentrations of fatty acids in normal human serum were 0.134 ± 0.009 μ mol/ml serum(n=5) for FA C_(16) and 0.052±0.028 μmol/ml serum(n=5)for FA C_(18),respectively.

一个基于PTE和PEL模式的科学推理模型

科学哲学家波普的猜想/反驳模式PTE描述了科学发现的一般程序,但这个模式是有问题的,它没有说明根据什么去猜想。高奇的PEL模式描述了科学推理的微观过程,但缺乏科学检验环节。文章提出的QHS[PEL]EEp模型将PTE和PEL进行整合,给出了一个更合理的科学推理模型。

基于PEL模型的管理制度科学性批判

制度创新在当今社会对于组织生存与发展具有重要意义,随着制度创新的步伐加快,对制度的评价和反思也越显其重要性。对于制度科学性,最终要由实践来检验,但对新制度科学性进行批判性的思考也是非常必要的。从科学证明模型PEL出发,分析如何对管理制度科学性进行评价。

基于PEL模型的管理制度科学性评价

高奇在《科学方法实践》中提出的PEL模型,是提供所需要的预设、证据和逻辑去支持一个给定的科学结论的科学证明模型,也是对科学理论进行评价的模型。本文尝试将这一模型运用于管理评价中,分别从管理预设、管理中的制度以及管理论证中的逻辑三个方面对管理制度的科学性评价进行研究。

New Opportunities for Lanthanide Luminescence

Trivalent lanthanide ions display fascinating optical properties. The discovery of the corresponding elements and their first industrial uses were intimately linked to their optical properties. This relationship has been kept alive until today when many high-technology applications of lanthanide-containing materials such as energy-saving lighting devices, displays, optical fibers and amplifiers, lasers, responsive luminescent stains for biomedical analyses and in cellulo sensing and imaging, heavily rely on the brilliant and pure-color emission of lanthanide ions. In this review we first outlined the basics of lanthanide luminescence with emphasis on f-f transitions, the sensitization mechanisms, and the assessment of the luminescence efficiency of lanthanide-containing emissive molecular edifices. Emphasis was then put on two fast developing aspects of lanthanide luminescence： materials for telecommunications and light emitting diodes, and biomedical imaging and sensing. Recent advances in NIR-emitting materials for plastic amplifiers and waveguides were described, together with the main solutions brought by researchers to minimize non-radiative deactivation of excited states. The demonstration in 1999 that erbium tris（8-hydroxyquinolinate） displayed a bright green emission suitable for organic light emitting diodes （OLEDs） was followed by realizing that in OLEDs, 25% of the excitation energy leads to singlet states and 75% to triplet states. Since lanthanide ions are good triplet quenchers, they now also play a key role in the development of these lighting devices. Luminescence analyses of biological molecules are among the most sensitive analytical techniques known. The long lifetime of the lanthanide excited states allows time-resolved spectroscopy to be used, suppressing the sample autofluorescence and reaching very low detection limits. Not only visible lanthanide sensors are now ubiquitously provided in medical diagnosis and in cell imaging, but the feasibility of using NIR emission of ions such as YbⅢ is now being tested because of deeper penetration in biological tissues.

Luminescence Properties of Green-Emitting Phosphor (Ba_(1-x),Sr_x_2SiO_4∶Eu^(2+) for White LEDS

The （Ba1- x, Srx ） 2 SiO4 ： EU^2＋ green-emitting phosphors were synthesized by conventional solid-state reaction in a CO-reductive atmosphere, and their luminescent properties were investigated. The XRD data show that the Ba/Sr ratio not only affects the lattice parameters, but also influences the emission peak. The excitation spectra indicate that this phosphor can be effectively excited by UV light from 370 to 470 nm. The emission band is due to the 4f^65d^1→4f^7 transition of the Eu^2＋ ion. With an increase in x, the emission band shifts to longer wavelength and the reason was discussed. The emission spectra exhibit a satisfactory green performance under different excitation wavelength（380,398,412,420,460 nm）. （Ba1- x, Srx ） 2 SiO4 ： EU^2＋ is a promising phosphor for green white-lighting-emission diode by ultraviolet chip.

Combustion synthesis and luminescence properties of LaPO4： Eu （5%）

Rare earth doped materials are an important type of phosphors due to their excellent performance such as stability at high temperature and light emission covering the entire visible domain. The combustion synthesis at acid pH of the monoclinic LaPO4： Eu（5%） powders was described. A mixture of La（NO3）3·6H2O, EuCly6H2O and （NH4）2HPO4 was used as anion precursor and glycin as fuel. The synthesis was followed by structure, morphology characterisation and luminescent properties of the obtained compound. The room temperature emission measurements under ultraviolet excitation at 254 nm were made for the emission transition ^5D0→^7FJ of this phosphor. The CIE （Commission Intemationale de L＇Eclairage） chromatic coordinates, dominant wavelength and colour purity were determined and compared to other luminescent materials obtained by other methods.

Relationship between Crystal Structure and Luminescence Properties of (Y_(0.96-x)Ln_xCe_(0.04))_3Al_5O_(12) (Ln=Gd, La, Lu) Phosphors

The doping effects of La^3＋, Gd^3＋ and Lu^3＋ on the crystal structure and luminescence properties of （Yo96-x LnxCe0.04）3Al5O12（Ln = Gd, La, Lu） phosphors were studied. The X-ray diffraction patterns presented that with the inerease of the doping concentrations of La^3＋ and Gd^3＋ ions, the d-value of （Y0.96-xLnxCe0.04）3Al5O12 （Ln = Gd, La） inereased and the larger the doping ion, the stronger the effect would be. The doping amount causing phase transition in （Y0.96-xLnxCe0.04）3Al5O12 decreased with the inerease of the ionic radii of the doping lanthanide ions （La^3＋： 0.106 nm, Gd^3＋： 0. 094 nm, Lu^3＋ ： 0.083 nm）. The bigger doping ion of Gd^3＋ made the emission of （Y0.96-xGdxCe0.04）3Al5O12 move to red spectral region, but the smaller one of Lu^3＋ made it blue.

Preparation and luminescence properties of the red-emitting phosphor(Sr_(1-x)Ca_x)_2Si_5N_8:Eu^(2+) with different Sr/Ca ratios

A series of Eu2＋-doped ternary nitride phosphors, with a formula of（Sr1-xCax）2Si5N8：Eu2＋, were synthesized by high-temperature solid-state method.The structure and luminescence properties were characterized, indicating the potential application as a red phosphor in the phosphor-converted white light-emitting diodes.The X-ray diffraction patterns showed that the Sr2Si5N8 and Ca2Si5N8 phases were generated at each end of（Sr1-xCax）2Si5N8：Eu2＋ and coexisted in the range of 0.5≤x≤0.75.The emission spectra showed broad emission bands originating from the 4f65d1→4f7 transition of Eu2＋ ions.The emission peak changed with the variations in Ca2＋ concentration.

Electronic structure of the SrAl_2O_4:Eu^(2+) persistent luminescence material

The electronic structure of the strontium aluminate （SrAl2O4：Eu^2＋） materials was studied with a combined experimental and theo- retical approach. The UV-VUV synchrotron radiation was applied in the experimental study while the electronic structure of the non-optimized and optimized crystal structure were investigated theoretically by using the density functional theory. The structure of the valence and conduction bands as well as the band gap energy of the material together with the position of the Eu2＋ 4f7 85712 ground state were calculated. The calculated band gap energy （6.4 eV） agreed well with the experimental value of 6.6 eV. The valence band consisted mainly of oxygen states whereas the bottom of the conduction band of strontium states. In agreement with the experimental results, the calculated 4f7 8S7r2 ground state of Eu2＋ lies in the energy gap of the host. The position of the 4f7 ground state depended on the Coulomb repulsion strength. The position of the 4f7 ground state with respect to the valence and conduction bands was discussed using theoretical and experimental evidence available.

Study on Luminescence Properties and Crystal-Lattice Environment of Eu^(2+) in Sr_(4-x)Mg_x Si_3O_8Cl_4∶Eu^(2+) Phosphor

According to the Van Uitert experimental equation, crystal-lattice environment of Eu^(2+) in the Sr_4Si_3O_8Cl_4 crystal was discussed. By adding Mg^(2+) to the host lattice, Sr_(4- x )Mg_ x Si_3O_8Cl_4∶Eu^(2+) was synthesized and the emission peak shifted from blue-green (488 nm) to blue-violet (411 nm) with the increase of amount of the magnesium which replaced the strontium. By analyzing the spectra of Sr_(4- x )Mg_ x Si_3O_8Cl_4∶Eu^(2+) the two Eu^(2+) emission centers were found because of the change of crystal-lattice environment in the host and the crystal structure was obtained by X-ray diffraction data.