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In-situ Horizontal Extrusion Test of Herbaceous Root-Soil with Different Root Types
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作者 Fangcui Liu Shengwen Qi +8 位作者 Shenglin Qi Xiaokun Hou Yanrong Li Guangming Luo Lei Xue Xueliang Wang Juanjuan Sun Songfeng Guo Bowen Zheng 《Journal of Earth Science》 SCIE CAS CSCD 2024年第3期918-928,共11页
The influence of different types of roots on the soil is complex and still remains unclear.Four in-situ extrusion tests were conducted on two types of root systems,namely fibrous and tap root system,for three plants,E... The influence of different types of roots on the soil is complex and still remains unclear.Four in-situ extrusion tests were conducted on two types of root systems,namely fibrous and tap root system,for three plants,Eleusine indica,Potentilla anserine,and Artemisia argyi,according to the classification in Botany,and the thrust-displacement curves and failure patterns of different samples were analysed by comparison to fill the aforementioned gap.Results reveal that the roots can reduce the characteristics of soil brittleness and enhance its capability to resist large deformation,and different root types contribute different effects to the strain-hardening behavior of the root-soil mass.The contribution of the fibrous root system to strength is limited,whilst the tap root system substantially enhances strength and stiffness.Results of failure patterns show that fibrous and tap root systems affect soil solidification and surface cracking reduction.However,the effect of the tap root system depends on the composition of lateral and tap roots:long and rich lateral roots are effective for resisting the creation of cracks,but thick tap roots with few and thin lateral roots may lead to several surface cracks. 展开更多
关键词 root types fibrous root tap root in-situ horizontal extrusion test root-soil cracks slope protection.
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Efficacy observation on cervical spondylosis of nerve root type treated by the warm needling at Jiájǐ(夹脊EX-B 2) and tapping with plum-blossom needle 被引量:1
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作者 刘敏娟 穆敬平 +2 位作者 郑苏 任昌菊 WANG Fang 《World Journal of Acupuncture-Moxibustion》 2013年第4期6-10,共5页
Objective To observe the clinical effect on cervical spondylosis of nerve root type treated by warm needling therapy at Jiáj (夹脊 EX-B 2) and plum-blossom needle therapy. Methods According to the random number... Objective To observe the clinical effect on cervical spondylosis of nerve root type treated by warm needling therapy at Jiáj (夹脊 EX-B 2) and plum-blossom needle therapy. Methods According to the random number table, 150 cases of cervical spondylosis of nerve root type were randomized into an acupuncture-moxibustion group (75 cases) and a control group (75 cases). In the acupuncture-moxibustion group, the warm needling at EX-B 2 and tapping with plum-blossom needle were applied. EX-B 2 on the affected segments were selected and stimulated with warm needling technique for 20– 30 min. Afterward, the plum-blossom needle was used to tap the skin around the acupoints, for 3 min on each site. The treatment was given once every day. Seven treatments made one session. The interval between two sessions was 1 day. In the control group, the medication was used in combination with traction therapy. The intravenous drip with 5% glucose 250 mL and compound salvia miltiorrhiza injection 40 mL was used, once a day. In traction treatment, the patient was in a sitting position, neck anteflexion at 15°–30°, traction force at 10%–20% of the body mass, for 20–30 min in each time. The treatment was given once every day. The appointed person evaluated therapeutic effects after the three sessions of treatment in the two groups. Results The clinical curative rate was 49.3% (37/75) and the total effective rate was 94.7% (71/75) in the acupuncture-moxibustion group and those were 24.0% (18/75) and 81.3% (61/75) respectively in the control group. The total effective rate and clinical curative rate in the acupuncture-moxibustion group were superior to the control group (both P0.05). In the comparison of the duration of treatment and effect in the cured patients between the two groups, the curative rate in the 1st session of treatment in the acupuncture-moxibustion group was higher than that in the control group (P0.05). In the comparison of the 6-month follow-up visit in the cured patients between the two groups, the effect in the acupuncture-moxibustion group was much more stable (P0.05). Conclusion The warm needling therapy at EX-B 2 and tapping therapy with plum-blossom needle achieve the significant effect on cervical spondylosis of nerve root type. 展开更多
关键词 cervical spondylosis of nerve root type warm needling therapy Jiáj(夹脊 EX-B 2) tapping therapy with plum-blossom needle
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A CLINICAL OBSERVATION ON THE THERAPEUTIC EFFECT OF CERVICAL SPONDYLOPATHY OF NERVE ROOT TYPE TREATED BY COMBINED CERVICAL TRACTION AND ELECTROACUPUNCTURE
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作者 何涛 何岚 《World Journal of Acupuncture-Moxibustion》 2004年第4期20-23,共4页
Objective: To observe the therapeutic effect of combined cervical traction and electroacupuncture (EA) on Cervical Spondylopathy of Nerve Root Type (CSNRT). Methods: 145 patients diagnosed as CSNRT were randomized int... Objective: To observe the therapeutic effect of combined cervical traction and electroacupuncture (EA) on Cervical Spondylopathy of Nerve Root Type (CSNRT). Methods: 145 patients diagnosed as CSNRT were randomized into 3 groups: combined treatment group, EA group, and cervical traction (CT) group. The combined group was treated with traction followed by EA of Dazhui (大椎 GV 14), Fengchi (风池 GB 20), cervical Jiaji (夹脊 EX-B 2), etc.. Patients of two control groups were only treated by either CT or EA. Results: The markedly-effective rate and total effective rate were 76.0% and 94.0% respectively in the combined treatment group, 62.5% and 81.25% respectively in CT group, and 63.82% and 82.97% respectively in EA group. The therapeutic effect of the combined treatment group was significantly superior to that of two control groups (P<0.05). At 6-month follow-up, the above two markedly-effective and total effective rates in the combined treatment group remained 74.0% and 92.0%, still significantly higher than that in two control groups. Conclusion: Combining cervicle traction with EA treatment can effectively eliminate or relieve the symptoms and signs in patients with nerve root type cervical spondylopathy. 展开更多
关键词 Cervical spondylopathy of nerve root type Cervical traction Electroacupuncture
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CLINICAL OBSERVATION ON TREATMENT OF NERVE-ROOT TYPE CERVICAL SPONDYLOSIS WITH ACUPUNCTURE, TRACTION PLUS SELF-EXERCISE OF QIGONG
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作者 李庆雯 郭义 +2 位作者 王惠琴 郑万鹏 郑昆仑 《World Journal of Acupuncture-Moxibustion》 2002年第2期45-47,共3页
Purpose: To observe the therapeutic effect of acupuncture combined with traction and Qigong exercise for treatment of nerve root type cervical spondylosis. Methods: A total of 130 nerve root type cervical spondylosis ... Purpose: To observe the therapeutic effect of acupuncture combined with traction and Qigong exercise for treatment of nerve root type cervical spondylosis. Methods: A total of 130 nerve root type cervical spondylosis patients were randomly divided into acupuncture + traction + Qigong exercise (ATQE) group (n=59), acupuncture + Qigong exercise (AQE) group (n=40) and traction + Qigong exercise (TQE) group (n=31). Main acupoints used were Fengchi (GB 20) and cervical Jiaji (EX B 2) on the affected side. Results: After one month’s treatment, in ATQE, AQE and TQE groups, 43 (72.88%), 18 (45.00%) and 12 (45.16%) had remarkable amelioration, 14 (23.72%), 14 (35.00%) and 10 (32.26%) were effective, and 2 (3.39%), 8 (20.00%) and 7 (22.58%) had no apparent changes with the total effective rates being 96.61%, 80.00% and 77.41% respectively. The therapeutic effect of ATQE group was significantly superior to that of AQE and TQE groups (P<0.01). 展开更多
关键词 Acupuncture Mechanical traction Qigong exercise Nerve root type cervical spondylosis
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Wet Cupping Therapy Improves Local Blood Perfusion and Analgesic Effects in Patients with Nerve-Root Type Cervical Spondylosis 被引量:41
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作者 MENG Xiang-wen WANG Ying +6 位作者 PIAO Sheng-ai LV Wen-tao ZHU Cheng-hui MU Ming-yuan LI Dan-dan LIU Hua-peng GUO Yi 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2018年第11期830-834,共5页
Objective: To observe wet cupping therapy(WCT) on local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis(NT-CS). Methods: Fifty-seven NT-CS patients were randomly divid... Objective: To observe wet cupping therapy(WCT) on local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis(NT-CS). Methods: Fifty-seven NT-CS patients were randomly divided into WCT group and Jiaji acupoint-acupuncture(JA) group according a random number table. WCT group(30 cases) was treated with WCT for 10 min, and JA group(27 cases) was treated with acupuncture for 10 min. The treatment efficacies were evaluated with a Visual Analogue Scale(VAS). Blood perfusion at Dazhui(GV 14) and Jianjing(GB 21) acupoints(affected side) was observed with a laser speckle flowmetry, and its variations before and after treatment in both groups were compared as well. Results: In both groups, the VAS scores significantly decreased after the intervention(P〈0.01), while the blood perfusion at the two acupoints significantly increased after intervention(P〈0.05); however, the increasement magnitude caused by WCT was obvious compared with JA(P〈0.05). Conclusion: WCT could improve analgesic effects in patients with NT-CS, which might be related to increasing local blood perfusion of acupunct points. 展开更多
关键词 wet cupping nerve-root type cervical spondylosis blood perfusion amount acupuncture Jiaji acupoint
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The type, position and age effect on the cutting reproduction of Picea crassifolia and its rooting mechanism in the Qilian Mountains 被引量:7
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作者 Jianjun Kang Wenzhi Zhao +3 位作者 Ming Zhao Guangyu Li Jiqiang Zhang Zhisheng Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期993-1002,共10页
Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its r... Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types (softwood, hardwood and root), positions (top, upper, middle and bottom) and ages (7, 10, 15, 20, 25 year-old) were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings (0.5-1.0 cm in diameter) from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid (IAA) and total carbon (TC) rather than abscisic acid (ABA) and total nitrogen (TN). The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings (0.5-1.0 cm in diameter) from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia. 展开更多
关键词 Picea crassifolia Kom type Positionand age effect Cutting reproduction rooting rate HORMONES Organic substances
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磁共振平衡稳态快速梯度回波序列在儿童神经根型骶管囊肿术前评估与定位中的价值
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作者 李林 赵建设 +2 位作者 易明岗 董春华 崔若棣 《分子影像学杂志》 2025年第10期1257-1262,共6页
目的探讨磁共振平衡稳态快速梯度回波序列(3D_BFFE)在儿童神经根型骶管囊肿术前评估与定位中的价值。方法回顾性分析2018年4月~2024年12月就诊于山东大学附属儿童医院神经外科的47例神经根型骶管囊肿患儿MRI及临床资料,其中男性31例,女... 目的探讨磁共振平衡稳态快速梯度回波序列(3D_BFFE)在儿童神经根型骶管囊肿术前评估与定位中的价值。方法回顾性分析2018年4月~2024年12月就诊于山东大学附属儿童医院神经外科的47例神经根型骶管囊肿患儿MRI及临床资料,其中男性31例,女性16例。本研究中所有患儿均行MRI常规序列及3D_BFFE与三维高分辨神经成像(3D_NerveVIEW)两种不同神经根成像序列扫描,并分别进行三维重建获取神经根与囊肿关系的图像。对比上述两种序列在显示神经根走行及神经根与囊肿关系中的差异,包括神经根在囊肿内穿行的数量、神经根分支的数量及神经根贴囊肿壁走行的数量,并与手术结果进行对照。结果手术证实47例患儿中,31例神经根在囊肿内穿行,3D_BFFE能够清晰显示28例走行路径、2例显示略模糊,仅1例无法显示其走行路径,而3D_NerveVIEW只能清晰显示2例神经根的走行路径,其余大部分显示较模糊或无法辨认神经根走行路径,两者差异有统计学意义(P<0.001);22例神经根分支患儿中,3D_BFFE能够清晰显示20例神经根走行路径,只有1例较模糊、1例无法显示,而3D_NerveVIEW只能清晰显示2例神经根走行路径,其余均显示不佳,差异有统计学意义(P<0.001);手术证实神经根贴壁走行16例,3D_BFFE能够清晰显示12例神经根与囊肿的关系,其余为模糊或无法显示,而3D_NerveVIEW只能清晰显示2例,其余均显示不佳,差异有统计学意义(P<0.001)。3D_BFFE在显示神经根在囊肿内走行路径、神经根分支的数量及神经根与囊肿壁的关系中明显优于3D_NerveVIEW序列,与术中结果基本一致。结论3D_BFFE可以清楚显示神经根走行与囊肿的关系,能够为手术方案的制定提供更为确凿、可靠的依据,从而避免了对神经根的损伤。 展开更多
关键词 磁共振成像 平衡稳态快速梯度回波 神经根型骶管囊肿
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常规西医方案联合经络刮痧治疗神经根型颈椎病的效果观察
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作者 王蓓 王芸 《中外医药研究》 2025年第11期88-90,共3页
目的:观察常规西医方案联合经络刮痧治疗神经根型颈椎病的效果。方法:选取2022年1月—2023年12月江苏省中医院收治的69例神经根型颈椎病患者作为研究对象,基于随机数字表法分为对照组(n=34,给予常规西医治疗)与观察组(n=35,给予常规西... 目的:观察常规西医方案联合经络刮痧治疗神经根型颈椎病的效果。方法:选取2022年1月—2023年12月江苏省中医院收治的69例神经根型颈椎病患者作为研究对象,基于随机数字表法分为对照组(n=34,给予常规西医治疗)与观察组(n=35,给予常规西医联合经络刮痧治疗)。比较两组疼痛情况、中医证候积分、颈椎功能、炎性因子水平、治疗效果。结果:治疗后,两组数字评分法评分降低,观察组低于对照组(P<0.001);治疗后,两组主证、次证评分及总分降低,观察组低于对照组(P<0.05);治疗后,两组颈椎功能障碍指数量表评分降低,观察组低于对照组(P<0.001);治疗后,两组白细胞介素-6、C反应蛋白、肿瘤坏死因子-α水平降低,观察组低于对照组(P<0.05);观察组治疗总有效率高于对照组(P=0.005)。结论:常规西医方案联合经络刮痧治疗神经根型颈椎病的效果显著,可减轻疼痛,缓解临床症状,改善颈椎功能,降低炎性因子水平。 展开更多
关键词 神经根型颈椎病 经络刮痧 甲泼尼龙琥珀酸钠 塞来昔布
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黄棕壤典型草地不同根系结构土壤团聚体稳定性季节变化特征 被引量:2
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作者 杨程高歌 雷少华 +5 位作者 耿韧 周岩 金秋 赵广举 卢慧中 孙国昌 《水土保持研究》 北大核心 2025年第1期66-72,共7页
[目的]探究黄棕壤草地不同根系结构下土壤团聚体稳定性随季节的变化特征及其影响因素,为区域水土流失治理提供理论和实践依据。[方法]借助配对T检验分析须根系(狗尾草)、直根系(青蒿)和裸地对照3类样地间土壤团聚体稳定性季节变化差异,... [目的]探究黄棕壤草地不同根系结构下土壤团聚体稳定性随季节的变化特征及其影响因素,为区域水土流失治理提供理论和实践依据。[方法]借助配对T检验分析须根系(狗尾草)、直根系(青蒿)和裸地对照3类样地间土壤团聚体稳定性季节变化差异,借助Pearson相关分析确定影响土壤团聚体稳定性季节变化的因素,并使用回归分析建立土壤团聚体稳定性拟合方程。[结果]狗尾草样地和青蒿样地土壤团聚体稳定性随季节变化出现明显的波动,均与裸地样地差异性显著(p<0.05),但二者之间差异性不显著(p>0.05)。狗尾草样地和青蒿样地土壤团聚体稳定性受根系密度影响显著(p<0.05),此外,青蒿样地土壤团聚体稳定性与土壤紧实度存在显著相关性。非线性回归分析表明,土壤团聚体稳定性可以用根系密度和土壤紧实度很好地拟合(R^(2)=0.730,NSE=0.730)。[结论]两种草地的根系结构均可以提升黄棕壤的土壤团聚体稳定性,并显著影响土壤团聚体稳定性的季节变化特征。但不同根系结构对土壤团聚体稳定性的影响无明显差异。 展开更多
关键词 土壤团聚体稳定性 季节变化 植物根系 根系类型
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清种与混播对不同株型玉米根系竞争区域土壤温室气体排放与产量的影响 被引量:2
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作者 张书萍 赵海岩 +1 位作者 刘晶 肖万欣 《辽宁农业科学》 2025年第1期5-11,共7页
在大田条件下,采用双因素随机区组设计,主区为2种播种方式:一是清种平展型玉米农大108(SP1)和紧凑型玉米郑单958(SP2),另一是两个不同株型玉米品种按1∶1混播(MP),副区为根系竞争的2个不同区域,即0~20 cm土层的根系重叠区(CD)和非重叠区... 在大田条件下,采用双因素随机区组设计,主区为2种播种方式:一是清种平展型玉米农大108(SP1)和紧凑型玉米郑单958(SP2),另一是两个不同株型玉米品种按1∶1混播(MP),副区为根系竞争的2个不同区域,即0~20 cm土层的根系重叠区(CD)和非重叠区(CK)。在种植密度90 000株/hm^(2)条件下,通过动态测定土壤温湿度、全氮含量、温室气体和产量等指标,结果表明,整个生育期,MP处理下土壤温度总体上较SP2处理高2.9%、土壤湿度较SP2处理低3.1%;CK区域土壤湿度较CD区域高18.3%。与其他播种方式相比,SP2处理下土壤全氮含量比MP处理显著提高8.5%。整个生育期不同处理下N_(2)O和CO_(2)排放量顺序依次均表现是SP2处理>SP1处理>MP处理,且CD区域下的N_(2)O和CO_(2)排放量较CK区域分别减少7.3%和5.9%。SP2处理粒重、收获指数和产量均高于其他处理,该处理下产量与其他处理产量差异均达到了显著或极显著水平。综上,在密植条件下,与清种平展型品种和两个不同株型品种混播相比,清种紧凑型玉米品种可获得较高产量,同时,该处理根系竞争区域附近土壤全氮含量相对较高,根系重叠区与非重叠区土壤湿度差较大,温室气体排放量相对较多。 展开更多
关键词 播种方式 春玉米 株型 增密种植 根系重叠区 温室气体 产量
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Effects of curcumin on sodium currents of dorsal root ganglion neurons in type 2 diabetic neuropathic pain rats
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作者 Bo MENG Lu-lu SHEN +4 位作者 Xiao-ting SHI Yong-sheng GONG Xiao-fang FAN Jun LI Hong CAO 《中国应用生理学杂志》 CAS CSCD 2015年第6期541-548,共8页
Along with the development of economy and society, type 2 diabetic mellitus(T2DM) has become one of the most common diseases at the global level. As one of the complications of T2 DM, diabetic neuropathic pain(DNP) st... Along with the development of economy and society, type 2 diabetic mellitus(T2DM) has become one of the most common diseases at the global level. As one of the complications of T2 DM, diabetic neuropathic pain(DNP) stubbornly and chronically affects the health and life of human beings. In the pain field, dorsal root ganglion(DRG) is generally considered as the first stage of the sensory pathway where the hyperexcitability of injured neurons is associated with different kinds of peripheral neuropathic pains. The abnormal electrophysiology is mainly due to the changed properties of voltage-gated sodium channels(VGSCs) and the increased sodium currents(INa). Curcumin is an active ingredient extracted from turmeric and has been demonstrated to ameliorate T2 DM and its various complications including DNP effectively. The present study demonstrates that the INa of small-sized DRG neurons are significantly increased with the abnormal electrophysiological characteristics of VGSCs in type 2 diabetic neuropathic pain rats. And these abnormalities can be ameliorated efficaciously by a period of treatment with curcumin. 展开更多
关键词 背根神经节神经元 2型糖尿病 姜黄素 钠电流 神经痛 大鼠 DRG神经元 电压门控钠通道
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高密度条件下株型改良对春玉米根-冠特征及籽粒产量的影响 被引量:2
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作者 赵耀 程前 +5 位作者 徐田军 刘正 王荣焕 赵久然 陆大雷 李从锋 《中国农业科学》 北大核心 2025年第7期1296-1310,共15页
【目的】增加种植密度是目前生产上提升玉米产量的主要农艺措施之一,但增密会导致群体结构不合理进而降低光照等有限资源利用效率,限制玉米产量潜力释放。基因编辑可以通过改良玉米株型来优化冠层结构使其适应密植进而增加产量,探明株... 【目的】增加种植密度是目前生产上提升玉米产量的主要农艺措施之一,但增密会导致群体结构不合理进而降低光照等有限资源利用效率,限制玉米产量潜力释放。基因编辑可以通过改良玉米株型来优化冠层结构使其适应密植进而增加产量,探明株型改良对春玉米根冠特性、籽粒产量及密度响应的影响及机制,可为春玉米的株型改良和密植高产提供理论与技术支撑。【方法】于2019和2020年在吉林省公主岭试验站进行为期2年的田间试验,以京科968和该品种的株型改良型品种京科Y968为试验材料,设置3个种植密度分别为6.0万株/hm^(2)(D1)、7.5万株/hm^(2)(D2)、9.0万株/hm^(2)(D3)。研究相同遗传背景下株型对春玉米根-冠特征和产量的影响。【结果】在D1条件下,2种不同株型的春玉米品种间叶面积指数(LAI)、净光合速率(Pn)、光能利用效率(PUE)、干物质积累量及籽粒产量均无显著差异。但与京科968相比,京科Y968在D3条件下具有相对较高的主根条数(7.2%)和较大的根系干物质重量(6.0%),促进了营养物质的吸收;同时,在D2和D3条件下,京科Y968植株上部、中部和下部均具有相对较低的茎叶夹角和较高叶向值、叶面积指数。因此,D2和D3条件下灌浆中后期京科Y968穗位叶的Pn分别提高了7.5%和7.7%,PUE提高了4.3%和10.8%。结构方程模型分析表明,较高的叶向值和叶面积指数可正向直接地提升地上部干物质积累量,进而增加籽粒产量8.7%(D2)和11.2%(D3)。【结论】株型的改良使京科Y968在高密度条件下具有更高的主根条数和更大的根系干物质重,有利于地下部营养吸收,同时其叶片更为紧凑,光合速率显著提高,冠层光能利用率得到有效提升,根-冠结构更为合理,促进了地上部干物质积累,进而可以获得相对较高的籽粒产量。 展开更多
关键词 春玉米 种植密度 株型改良 根系特性 冠层结构
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基于根系类型组合的护坡植物根系生态位特征
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作者 耿莞 陈济丁 +4 位作者 孔亚平 陶双成 赵倩 李金波 宋桂龙 《生态学报》 北大核心 2025年第4期1913-1924,共12页
根系生态位特征是护坡植物选择的重要依据,而具有不同根系生态位特征的植物组合,直接影响坡面土体的固持和植被恢复效果。选取了4种根系类型的常用护坡植物,分别为垂直轴根型灌木紫穗槐(Amorpha fruticosa L.)、水平轴根型灌木胡枝子(Le... 根系生态位特征是护坡植物选择的重要依据,而具有不同根系生态位特征的植物组合,直接影响坡面土体的固持和植被恢复效果。选取了4种根系类型的常用护坡植物,分别为垂直轴根型灌木紫穗槐(Amorpha fruticosa L.)、水平轴根型灌木胡枝子(Lespedeza bicolor Turcz.)、根蘖型草本紫花苜蓿(Medicago sativa L.)、丛生型草本高羊茅(Festuca arundinacea),依据根系类型进行了9种组合,采用湿法客土喷播对模拟边坡进行修复治理,研究不同植物组合的根系生态位特征,以明确不同类型根系之间错综复杂的位置关系及生态功能,为边坡修复植物选择及加固坡面稳定提供一定参考。研究结果表明:(1)不同根系结构类型组合在土层的空间分布具有显著差异。在0—10 cm土层中,高羊茅组合的根长及根干重百分比显著高于其他组合为86.9%和90.83%;而紫穗槐+苜蓿组合则在5 cm以下的土层中显著高于其他组合,为63.73%和76.52%。(2)不同组合根系生态位指数均随径级数量的增加而递减,均呈现反J型。高羊茅组合和胡枝子组合根系生态位指数均随土层深度的增加先升高后降低,其余组合随土层深度的增加而降低。高羊茅组合垂直空间生态位变化最大,其变幅为0.21—3.51。在10 cm以下土层中,除紫穗槐+苜蓿组合外的其余组合生态位指数均显著下降表现为表层聚集生态位型。(3)生态位指数最高的组合是紫穗槐+胡枝子,为1。紫穗槐+胡枝子+高羊茅组合的细根生态位宽度指数、生态位重叠度及地下种间竞争指数均显著高于其他组合,分别为0.089、0.036和0.438,种间竞争强度最大。综合不同根系类型植物组合的根系生态位特征,表现较好的根系类型组合为垂直轴根型+水平轴根型的紫穗槐+胡枝子组合、垂直轴根型+水平轴根型+丛生型的紫穗槐+胡枝子+高羊茅组合、根蘖型苜蓿组合和垂直轴根型+根蘖型的紫穗槐+苜蓿组合。 展开更多
关键词 模拟边坡 根系类型组合 根系生态位 生态位宽度 生态位重叠
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轴向间隙对罗茨式氢气循环泵性能的影响
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作者 秦佳 李伟 +2 位作者 季磊磊 胡敬宁 李硕 《中南大学学报(自然科学版)》 北大核心 2025年第3期1174-1183,共10页
基于动网格技术,采用SST(shear stress transport)k-ω湍流模型对罗茨式氢气循环泵模型进行数值仿真,利用相关试验证明了数值仿真的可靠性,研究了轴向间隙的取值对罗茨式氢气循环泵内部流场及性能的影响,阐明了轴向间隙的变化与泵出口... 基于动网格技术,采用SST(shear stress transport)k-ω湍流模型对罗茨式氢气循环泵模型进行数值仿真,利用相关试验证明了数值仿真的可靠性,研究了轴向间隙的取值对罗茨式氢气循环泵内部流场及性能的影响,阐明了轴向间隙的变化与泵出口脉动特性的关系。研究结果表明:随着轴向间隙增大,高温回流导致泵腔内流体的压力和温度显著升高、流速显著加快,间隙处的高速回流涡影响范围逐渐扩大,泵的出口流量逐渐减小,容积效率逐渐降低,出口脉动特性逐渐提高;当轴向间隙取值范围在0.125~0.150 mm时,出口流量减少了2.8 m^(3)/h,容积效率降低了3.6%,出口流量脉动系数降低了0.04,泵的出口流量和出口脉动特性在此范围内变化最为平稳。因此,综合容积效率和流动稳定性,确定罗茨式氢气循环泵的轴向间隙合理的取值范围为0.125~0.150 mm。 展开更多
关键词 罗茨式氢气循环泵 轴向间隙 内流特性 脉动特性
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根技术及其全生命周期解构 被引量:2
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作者 房汉廷 《中国软科学》 北大核心 2025年第3期1-19,共19页
根技术创新是一个尚未纳入技术经济学和创新经济学深入研究的重要问题。基于创新元动力原理和生物学隐喻,发展并再定义了根技术概念,即根技术(root technology)是从一个技术种子引发,经过向下筑根,实现向上涌现,继而在某个临界点产生爆... 根技术创新是一个尚未纳入技术经济学和创新经济学深入研究的重要问题。基于创新元动力原理和生物学隐喻,发展并再定义了根技术概念,即根技术(root technology)是从一个技术种子引发,经过向下筑根,实现向上涌现,继而在某个临界点产生爆发,最终成为泛在的元技术。研究结果表明:根技术本质上是其所在领域技术体系的“基因源代码”,是创造技术体系的技术,具有独特的生命周期——分期与变态同步发生,具有弱根技术、中根技术和强根技术3种分型,尤其是强根技术创新对创新链、产业链和价值链具有重要的不可替代的价值。这项研究成果是一项开拓性工作,为构建根技术创新范式、掌控创新链、把控产业链、操控价值链给出了理论指引和实践指导。 展开更多
关键词 根技术 根技术分期 根技术分型 根技术创新
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Expression of gamma-aminobutyric acid type A receptor α_2 subunit in the dorsal root ganglion of rats with sciatic nerve injury 被引量:1
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作者 Yu Lian Yang Wang +5 位作者 Ketao Ma Lei Zhao Zhongshuang Zhang Yuanyuan Shang Junqiang Si Li Li 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第32期2492-2499,共8页
The γ-aminobutyric acid neurotransmitter in the spinal cord dorsal horn plays an important role in pain modulation through primary afferent-mediated presynaptic inhibition. The weakening of γ-aminobutyric acid-media... The γ-aminobutyric acid neurotransmitter in the spinal cord dorsal horn plays an important role in pain modulation through primary afferent-mediated presynaptic inhibition. The weakening of γ-aminobutyric acid-mediated presynaptic inhibition may be an important cause of neuropathic pain. γ-aminobutyric acid-mediated presynaptic inhibition is related to the current strength of γ-aminobutyric acid A receptor activation. In view of this, the whole-cell patch-clamp technique was used here to record the change in muscimol activated current of dorsal root ganglion neurons in a chronic constriction injury model. Results found that damage in rat dorsal root ganglion neurons following application of muscimol caused concentration-dependent activation of current, and compared with the sham group, its current strength and γ-aminobutyric acid A receptor protein expression decreased. Immunofluorescence revealed that γ-aminobutyric acid type A receptor α2 subunit protein expression decreased and was most obvious at 12 and 15 days after modeling. Our experimental findings confirmed that the y-aminobutyric acid type A receptor α2 subunit in the chronic constriction injury model rat dorsal root ganglion was downregulated, which may be one of the reasons for the reduction of injury in dorsal root ganglion neurons following muscimol-activated currents. 展开更多
关键词 γ-aminobutyric acid γ-aminobutyric acid type A receptor α2 subunit neuropathic pain dorsal root ganglion whole-cell patch clamp IMMUNOFLUORESCENCE primary afferent depolarization paw withdrawal latency MUSCIMOL
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浙江安吉三种典型林分类型下土壤入渗特征及其影响因素
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作者 郭峰 杨思思 +6 位作者 张林 邱朝伟 魏侃俐 郭衍瑞 赵天衡 范长江 齐实 《土壤》 北大核心 2025年第4期903-910,共8页
本研究利用表置式双环测定仪测定了浙江安吉3种典型林分类型(毛竹纯林、毛竹-杉木混交林、杉木纯林)的入渗性能,并分析了土壤性质和根系特征对土壤入渗速率的影响。结果表明:(1)初始入渗速率(947.7~1220.5 mm/h)、第1阶段入渗速率(612.6... 本研究利用表置式双环测定仪测定了浙江安吉3种典型林分类型(毛竹纯林、毛竹-杉木混交林、杉木纯林)的入渗性能,并分析了土壤性质和根系特征对土壤入渗速率的影响。结果表明:(1)初始入渗速率(947.7~1220.5 mm/h)、第1阶段入渗速率(612.6~751.6 mm/h)、第2阶段入渗速率(479.0~591.3 mm/h)、第3阶段入渗速率(352.9~433.4 mm/h)、稳定入渗速率(272.0~369.0 mm/h)、平均入渗速率(373.1~498.2 mm/h)均随着毛竹入侵程度的增加而增加,除初始入渗速率外,其他入渗速率总体上表现为毛竹纯林>毛竹-杉木混交林>杉木纯林。(2)初始入渗速率、第1阶段入渗速率和平均入渗速率主要受0~10 cm土层黏粒含量以及10~20 cm土层细根(<2 mm)生物量和土壤容重的影响;第2阶段、第3阶段和稳定入渗速率主要受0~10 cm土层非毛管孔隙度和细根(<2 mm)生物量以及10~20 cm土层细根根长密度影响。(3)细根(<2 mm)生物量和根长密度可通过影响土壤非毛管孔隙、容重和黏粒含量间接影响土壤入渗速率。(4)Kostiakov模型是描述不同林分类型下土壤入渗过程的最佳模型。 展开更多
关键词 林分类型 土壤入渗 根系特征 土壤性质 毛竹
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氮肥类型对水稻机插育秧种子出苗及秧苗素质的影响
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作者 张鹏 钟刘泉显 +10 位作者 毋翔 马昕伶 陈惠哲 张玉屏 王亚梁 向镜 唐梅 王志刚 徐逸文 朱德峰 张义凯 《中国土壤与肥料》 北大核心 2025年第9期73-80,共8页
水稻机插秧技术是提高水稻生产效率和稳定增产的关键手段,施肥管理对秧苗的生长和成苗率至关重要。探讨了不同类型氮肥在水稻机插育秧过程中对出苗率、秧苗素质、根系发育及根际土壤养分含量的影响。以杂交水稻甬优1540和华浙优210为材... 水稻机插秧技术是提高水稻生产效率和稳定增产的关键手段,施肥管理对秧苗的生长和成苗率至关重要。探讨了不同类型氮肥在水稻机插育秧过程中对出苗率、秧苗素质、根系发育及根际土壤养分含量的影响。以杂交水稻甬优1540和华浙优210为材料,选用不同类型的氮肥,按照常规育秧方式设置不同氮用量(250~750 mg/kg)开展水稻育秧试验。结果表明,秧盘营养土施用硫酸铵时,纯氮用量250~500 mg/kg对水稻种子出苗率没有影响,显著提高水稻秧苗综合素质,增加秧苗根系盘结力;秧盘营养土施用尿素时,水稻种子的出苗和根系生长被显著抑制,出苗率和根系盘结力分别平均降低了9.7%和27.0%。与硫酸铵处理相比,尿素处理显著增加根际土壤中酰胺态氮的积累,对种子萌发和早期根系生长产生了毒害效应。水稻育秧土施用铵态氮肥(硫酸铵)较酰胺态氮(尿素)更有利于种子的出苗、秧苗素质和根系盘结力的提高,且纯氮适宜用量在250~500 mg/kg,可为水稻育秧施肥管理提供技术支撑与有效指导。 展开更多
关键词 水稻 氮肥类型 秧苗素质 出苗率 根系生长
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根土复合体与岩体接触面剪切试验
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作者 程鹏 谢玉江 +2 位作者 张文生 李锦辉 林建武 《科学技术与工程》 北大核心 2025年第14期6009-6015,共7页
为了研究岩质边坡生态防护中根土复合体与岩石接触面的作用机理,通过构建不同植物种类、护坡土体类型与岩石风化程度的接触面物理模型,在天然应力条件下,开展了根土岩接触面的直接剪切试验,揭示了接触面抗剪强度和剪切位移的变化规律,... 为了研究岩质边坡生态防护中根土复合体与岩石接触面的作用机理,通过构建不同植物种类、护坡土体类型与岩石风化程度的接触面物理模型,在天然应力条件下,开展了根土岩接触面的直接剪切试验,揭示了接触面抗剪强度和剪切位移的变化规律,并分析了植物根系形态、护坡土体类型、岩石风化程度对接触面抗剪强度的影响机理。结果表明,植物根系通过护坡土体并伸入基岩裂隙,显著提高了剪切带土体抗剪强度和土岩交界面抗滑移能力,从而增强了护坡土体与岩石的整体性;接触面抗剪强度与植物根系竖向延伸程度及岩石风化程度正相关,相较于无植物工况,当种植香根草时峰值抗剪强度提高了53.9%,强风化基岩条件下提高峰值强度达22.4%。相较于普通土,添加有黏合剂与团粒剂的基材土可显著提高土体抗剪性能,提升接触面峰值抗剪强度达20.1%。 展开更多
关键词 生态护坡 土-岩接触面 剪切试验 根系类型 基材土 风化程度
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根键布置对根式沉井竖向承载特性的影响
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作者 朱小军 孙淼淼 贾晓敏 《公路交通科技》 北大核心 2025年第2期119-130,共12页
【目标】研究根键层数、位置、个数、长度、截面形式及倾斜角度等因素对根式沉井竖向承载特性的影响。【方法】以马鞍山长江大桥5#根式沉井基础为原型设计了根式沉井1∶75缩尺模型,在自制多功能模型槽中开展了根式沉井竖向受荷室内模型... 【目标】研究根键层数、位置、个数、长度、截面形式及倾斜角度等因素对根式沉井竖向承载特性的影响。【方法】以马鞍山长江大桥5#根式沉井基础为原型设计了根式沉井1∶75缩尺模型,在自制多功能模型槽中开展了根式沉井竖向受荷室内模型试验,监测了根式沉井荷载-位移、井身内力及沉井周围的土体应力状态情况。【结果】相比3层根键沉井,5层、7层根键沉井的极限竖向承载力更高,并增大了沉井底部土体水平应力的分布范围;根键沿井身居中、靠下布置时,沉井的竖向承载力更高;同层布置根键数由4根增加至6根时,沉井的竖向承载力增加了23.09%,沉降减少了26.15%;根键长度由40 mm增加至50 mm时,沉井的承载力提高了10.27%;根键横截面形状对沉井的承载力影响较小;对比根键水平布置,根键向下倾斜15°布置时更利于控制沉井的沉降量。【结论】合理增加根键层数、长度、缩小同层根键径向间距,能够扩大根键对土体的影响范围,有效提升根式沉井基础的承载性能,并降低基础的沉降量;沿井身靠下布置根键时,底部土体反力大,土体对基础的支承效果更佳。研究成果可为根式沉井设计提供参考依据,推动根式沉井基础在桥梁建设中的广泛应用。 展开更多
关键词 桥梁工程 根键布置方式 模型试验 根式沉井 竖向承载特性
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