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Effect of fertigation frequency on soil nitrogen distribution and tomato yield under alternate partial root-zone drip irrigation

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Journal of Integrative Agriculture 2023年第3期22卷 897-907页

作者： FENG Xu-yu PU Jing-xuan liu hai-jun WANG Dan liu Yu-hang QIAO Shu-ting LEI Tao liu Rong-hao College of Water Resources Science and Engineering Taiyuan University of TechnologyTaiyuan 030024P.R.China College of Water Sciences Beijing Normal UniversityBeijing 100875P.R.China Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology Beijing Normal UniversityBeijing 100875P.R.China Shanxi Province Key Laboratory of Soil Environment and Nutrient Resources Taiyuan 030031P.R.China

Alternate partial root-zone drip fertigation (ADF) is a combination of alternating irrigation and drip fertigation,with the potential to save water and increase nitrogen (N) fertilizer efficiency.A 2-year greenhouse experiment was conducted to evaluate the effect of different fertigation frequencies on the distribution of soil moisture and nutrients and tomato yield under *** treatments included three ADF frequencies with intervals of 3 days (F3),6 days (F6) and 12 days (F12),and conventional drip fertigation as a control (CK),which was fertilized once every 6 *** the ADF treatments,two drip tapes were placed 10 cm away on each side of the tomato row,and alternate drip irrigation was realized using a manual valve on the distribution *** the CK treatment,a drip tape was located close to the roots of the tomato *** total N application rate of all treatments was 180 kg ha^(-1).The total irrigation amounts applied to the CK treatment were450.6 and 446.1 mm in 2019 and 2020,respectively;and the irrigation amounts applied to the ADF treatments were 60%of those of the CK *** F3 treatment resulted in water and N being distributed mainly in the 0–40-cm soil layer with less water and N being distributed in the 40–60-cm soil *** F6 treatment led to 21.0 and 29.0%higher 2-year average concentration of mineral N in the 0–20 and 20–40-cm soil layer,respectively and a 23.0%lower N concentration in the 40–60-cm soil layer than in the CK *** 2-year average tomato yields of the F3,F6,F12,and CK treatments were 107.5,102.6,87.2,and 98.7 t ha^(-1),*** tomato yield of F3 was significantly higher (23.3%) than that in the F12 treatment,whereas there was no significant difference between the F3 and F6 *** F6 treatment resulted in yield similar to the CK treatment,indicating that ADF could maintain tomato yield with a 40%saving in water *** on the distribution of water and N,and tomato yield,a fertigation frequency

关键词： alternate partial root-zone irrigation drip fertigation soil water soil mineral content tomato yield

Thermal Lens Determination of End-Pumped Solid-state Lasers by a Simple Direct Approach

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Chinese Physics Letters 1999年第3期16卷 181-183页

作者： liu jun-hai LU Jian-ren LÜjun-hua SHAO Zong-shu JIANG Min-hua National Laboratory of Crystal Materials Shandong UniversityJi’nan 250100

The stability of linear planar resonators involved in solid-state lasers is entirely decided by the thermal lens of the laser *** exists a critical point between stable state and unstable state at which the thermal focal length equals the distance from the center of the crystal to one end *** on this fact,a new method for measuring the thermal focal length of the laser crystal has been presented and applied to a Nd^(3+):YVO_(4) crystal at various absorbed pump power levels up to 10 *** results have shown to be in good agreement with theoretical calculation.

关键词： pump state crystal

Simultaneous Determination of Gold and Platinum by Double Artificial Neural Network Analysis with Flow-injection Chemiluminescence

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Chinese Chemical Letters 2006年第10期17卷 1343-1346页

作者： Ming Yang liu hai Tao ZHANG jun Feng LI Shu Gui CHEN Hong Yan WANG College of chemistry Jilin University Changchun 130012

A highly sensitive double artificial neural network （DANN） analysis with flow-injection chemiluminescence （FI-CL） has been developed to simultaneously determine the trace amounts of the gold and platinum in simula... 详细信息

关键词： Double artificial neural networks flow-injection chemiluminescence simultaneous determination gold and platinum.

Self-Frequency Doubling Laser Performance of Nd:GdCOB Crystal with a Phase-Matching Angle Out of the Principal Plane

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Chinese Physics Letters 1999年第9期16卷 651-652页

作者： LÜjun-hua LI Guang-ming liu jun-hai ZHANG Shu-jun CHEN Huan-chu JIANG Min-hua SHAO Zong-shu National Key Laboratory of Crystal Materials Shandong UniversityJinan 250100

The self-frequency doubling laser performance of Nd:GdCOB crystal cut in phase-matching direction(θ=66.3°,Ф=134.4°)was compared with the crystal cut in the direction of(θ=90°,Ф=46°).Results show that the former has a higher second-harmonic conversion efficiency than the *** Ti:sapphire laser as pumping source,a maximum of 11.3mW of green light has been obtained with an incident power of *** corresponds to an optical-optical conversion efficiency of 2.2%.Laser threshold for self-frequency doubling operation is measured to be 1 *** our knowledge,this is the lowest threshold achieved so far.

关键词： Nd: pumping Crystal

Growth and Second-Harmonic-Generation Properties of Tm^(3+), Yb^(3+), Bi^(3+) and Li^(+) Doped GdCa_(4)O(BO_(3))_(3) Crystals

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Chinese Physics Letters 2001年第3期18卷 388-389页

作者： ZHANG Shu-jun CHENG Zhen-Xiang ZHANG Shao-jun liu jun-hai HAN Jian-Ru WANG Ji-Yang CHEN Huan-Chu State Key Laboratory of Crystal Materials Shandong UniversityJi’nan 250100

The rare-earth ions(Yb^(3+),Tm^(3+))and Li^(+),Bi^(3+)ions doped GdCa_(4)O(BO_(3))_(3) crystals were grown using the Czochralski pulling *** second-harmonic-generation conversion efficiencies of the GdCOB:Yb and GdCOB:Tm crystals are 31.3%and 33.3%,respectively,while the undoped GdCOB crystal is 27.9%.The conversion efficiencies of Yb^(3+),Tm^(3+)doped GdCOB are improved by 12%and 19%,respectively,compared to that of the undoped *** conversion efficiencies of Li^(+),Bi^(3+)doped GdCOB crystals are 33%and 38.3%,which are improved by 15%and 37%as compared to that of the undoped *** results are discussed using the anion group theory.

关键词： Crystal (3) Harmonic

Silicon light emitting device in CMOS technology

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Optoelectronics Letters 2007年第2期3卷 85-87页

作者： liu hai-jun GU Ming liu Jin-bin HUANG Bei-ju CHEN Hong-da State Key Lab on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Science Beijing 100083 China

A novel silicon light emitting device was realized with standard 0.35μm 2P4M Mixed Mode/RF CMOS technology. The device functions in a reverse breakdown mode and can be turned on at 8.3 V and operated normally at a wide voltage range of 8.3 V-12.0 V. An output optical power of 13.6 nW was measured at the bias of 10 V and 100 mA, and the emitted light intensity was calculated to be more than 1 mW/cm2. The optical spectrum of the device is in the range of 500-820 nm.

关键词：硅发光器件 CMOS技术反向击穿模光输出功率

Diode-Laser-Array Single-End-Pumped 5W Nd:YVO_(4)/KTP Continuous-Wave Solid-State Green Laser

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Chinese Physics Letters 1999年第7期16卷 508-509页

作者： liu jun-hai WANG Chang-qing LU jun-hua LI Guang-ming SHAO Zong-shu WANG Ji-yang liu Yao-gang JIANG Min-hua National Laboratory of Crystal Materials Shandong UniversityJiJnan 250100

Continuous-wave radiation of 5W at 532 nm was produced with an Nd:YVO_(4)/KTP intracavity&equency-doubled laser end-pumped by a diode-laser-array at pump power of 17.2 W,giving optical conversion efRciency of 29.1%.The output power stability was measured to be better than 1.5%in short term *** pump-induced thermal lensing was also measured,showing good agreement with the performance of the laser.

关键词： Nd: pump pumped

Thermal Lensing Measurement and Laser Performance of End-Pumped Lightly Doped Nd:GdVO_(4) Crystal

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Chinese Physics Letters 1999年第11期16卷 814-815页

作者： liu jun-hai SHAO Zong-shu MENG Xian-lin ZHANG Huai-jin ZHU Li JIANG Min-hua National Laboratory of Crystal Materials Shandong UniversityJinan 250100

The thermal lensing effect generated in an end-pumped lightly doped Nd:GdVO4 crystal was found to be considerably weaker than that in Nd:YVO4 having the same Nd3+ concentration. Consequently, the laser performance of Nd:GdVO4 at high pump powers over 20 W was found to be superior to that of Nd:YVO4. TEM00 mode cw radiation of 14.3 W at 1.06μm was achieved with an optical conversion efficiency of 55%, and average slope efficiency of 62%.

关键词： Nd:GdVO4 Nd:YVO4 Crystal

Effect of Strontium Ion on the Growth and Second-Harmonic Generation Properties of GdCa_(4)O(BO_(3))_(3) Crystal

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Chinese Physics Letters 2001年第1期18卷 63-64页

作者： ZHANG Shu-jun CHENG Zhen-Xiang liu jun-hai HAN Jian-Ru WANG Ji-Yang SHAO Zong-Shu CHEN Huan-Chu State Key Laboratory of Crystal Materials Shandong UniversityJi'nan 250100

Large sized and optical quality GdCa_(4)O(BO_(3))_(3)(GdCOB)crystal with calcium partially substituted by strontium(Sr)ions was grown for the first *** x-ray powder diffraction shows that the Sr ion has an effect on the cell parameters of the GdCOB crystal Second-harmonic generation(SHG)experiments were performed on the Sr:GdCOB and GdCOB crystals along the spatial phase-matching *** results show that the cw green laser output power is 1.04 W when the laser diode pump power is 10 W in the Nd:YVO_(4)/Sr:GdCOB intracavity *** the slope efficiency of Nd:YVO_(4) and the fundamental laser in cavity,the intracavity SHG conversion efficiency of the GdCOB crystal is 21%while it is 24%for the Sr:GdCOB crystal,the SHG conversion efficiency is improved by 14%.The effect of the Sr ions on the nonlinearity of the GdCOB crystal is also discussed by using the anion group theory.

关键词： intracavity pump Crystal