203 research outputs found

    洱海流域水生态分区

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    分区边界的确定是生态分区的重要步骤,但目前多数水生态分区的边界确定以定性分析、专家判断为主。本研究以洱海流域为例,建立了一套两级分区体系。该体系基于GIS技术,用子流域作为分区基本单元,并用相关分析法,定量筛选一、二级分区指标。其中,一级分区指标为高程、坡度和植被归一化指数(NDVI),二级分区指标为农田百分比和城镇百分比。通过指标图层的叠加和重分类,合并同质性子流域,从而将洱海流域划分为5个一级区和9个二级区。藻类群落分布的验证结果表明分区合理。本研究将定量分析和子流域边界应用于水生态分区,使分区边界的确定更科学,在实际管理中更具有可操作性。本研究结果为水生态分区研究提供了新的方法,为洱海流域水生态管理提供了基本管理单元

    Talent recommendation system in big data era

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    1人才推荐系统的应用背

    Defect Detection of Solar Cells Based on Electroluminescence Imaging

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    为了检测太阳能电池存在的缺陷,给太阳能电池施加一定的正向偏压,利用CCd相机在暗室中探测电池的发光。探测分别在3种状态下进行:无滤光探测、过滤800 nM以下波长后探测和过滤800 nM以上波长后探测。研究发现:只有在过滤800 nM以下波长的镜片下探测效果最好,表明电池主要发红外光,其波长范围为850~1 200 nM。控制光探测器的探测时间,发现不同探测时间下电池的发光强度不同,探测时间相同但偏压不同则光强也不同。该方法可以检测出正向偏压下电池存在的各种缺陷类型。在反向电压下,薄膜电池会出现小光点,这表示缺陷区域和密度,研究证明薄膜电池也能发红外光且薄膜中存在区域缺陷。对低功率的电池片进行光探测发现,电池存在严重缺陷。上述结果表明,红外光探测可以直观、快速、方便地检测太阳能电池存在的缺陷。In order to detect the hidden defects of the solar cells,the eletroluminescence image was obtained by applying a certain forward bias voltage to solar cell in the darkroom using the light sensor CCD camera.The experiments were carried out at three states: without optical filter,filtering the wavelength less than 800 nm,and filtering the wavelength greater than 800 nm.It is found that the detection effect is the best only under the lens of filtration of less than 800 nm wavelength.It proves that the cell mainly emits infrared light of 850 ~ 1 200 nm.By controlling the detecting time,it is found that the light intensity is varied with the detection time,and also varied with the forward bias voltage in the same detection time.This method can detect all kinds of hidden defect type of the solar cells.Under the reverse voltage,thin film cell appears small spots which show defect area and density,and the studies prove that thin film cell also can send infrared light and the defects exist in the cell.In detecting low power cell,it is found that there are serious defects in the cell.The results show that infrared detection has rapid and convenient intuitive features for solar cells defect detection.福建省教育厅科研项目(985)资助项

    农村留守经历大学生成人依恋及影响因素分析

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    目的探讨农村留守经历大学生(URLB)成人依恋现状及其影响因素。方法采用亲密关系体验问卷及自编问卷对河北省2所高校1062名有农村留守经历的大学生进行自填式问卷调查。结果成人依恋回避和依恋焦虑维度平均得分分别为(4.16±0.53),(3.82±0.82)分;多元线性回归分析表明,性别(β=0.236)及与父母联系频次(β=0.073)为URLB依恋回避的影响因素;性别(β=0.079)、留守家庭生活满意度(β=-0.074)、开始留守时间(β=-0.12)及与抚养人沟通情况(β=0.066)为URLB依恋焦虑的影响因素。结论性别以及童年期的留守经历对URLB成人依恋的发展有影响

    Application of the three-dimensional visualization and 3D printing technology for the preoperative evaluation of retroperitoneal tumors

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    目的探讨三维重建及3D打印技术在腹膜后肿瘤术前评估中的应用价值。方法回顾性分析2011年3月至2015年9月厦门大学附属成功医院收治的50例腹膜; 后肿瘤病人的临床资料,应用人体器官三维建模软件将病人的CT二维图像重建成三维可视化图像,使用人体器官模型3D打印设备,用两色热塑性塑料打印实物模; 型,通过观察肿瘤与腹腔器官、腹部大血管之间的关系进行术前评估并制定手术方案。实施手术,术中比较重建结果与实际的区别。结果50例病人均成功完成三维; 重建,其中10例病人完成3D打印,三维重建结果及3D打印模型能够立体、清晰和实物化的显示肿瘤解剖学位置及与周围器官、血管的毗邻关系,与术中实际情; 况大致相符。50例病人均顺利施行手术,术中无死亡。结论三维重建及3D打印技术能够对腹膜后肿瘤术前进行精准评估,对指导手术具有一定的应用价值。Objective To explore the application value of three dimensional; visualization and 3D printing technology in the preoperative evaluation; of retroperitoneal tumors. Methods March 2011 to September 2015,the; clinical data of 50 cases of retroperitoneal tumor patients in Xiamen; University Affiliated successful hospital were retrospectively analyzed.; Xiamen strong science and technology R & D human organ 3D modeling; software will reconstruct 2D CT image visualization into a; three-dimensional visualization image,and then it can print physical; model with the company's XMQB-I human organ model 3D printing equipment; and white thermoplastic. At last,preoperative evaluation and surgical; plan can be made through the relationship between the tumor,organs in; abdominal cavity,and abdominal vascular. During the surgery,make a; comparison between the visualization results with the actual condition.; Results 50 cases of patients were successfully completed the; three-dimensional visualization,including 10 cases of patients; completed. Three-dimensional visualization and 3D printing model can; three-dimensionally,clearly show the adjacent relationship between the; anatomical tumour location and surrounding organs and blood; vessels,broadly in line with the actual surgery. 50 surgeries were; successfully performed,no death during perioperative period. Conclusion; Three dimensional visualization and 3D printing technology can make an; accurate preoperative evaluation of retroperitoneal tumors,which has a; certain application value for guiding surgery.国家自然科学基

    Abundance and production of bacteria and their correlations with environmental factor

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    以2014年8月南海北部海水样品为研究对象,利用平板计数法和流式细胞仪计数法对南海北部表层和垂直海域可培养细菌和细菌总数分布状况进行研究,对细菌; 生产力进行测定,并结合环境因子进行相关性分析。结果表明:珠江口到南海北部海域,水平方向可培养细菌总数变化范围是3.70*10~2 ~; 1.42*10~3 CFU/mL,细菌总数变化范围是5.12 * 10~5 ~1.61 * 10~6; cells/mL,细菌生产力的变化范围是0.03 ~0.40 mg/m~3/h;垂直方向上可培养细菌变化范围是1.08 *10~3 ~9.00; *10~3 CFU/mL,细菌生产力变化范围是0.01 ~0.08; mg/m~3/h,其中表层海水中的细菌生产力明显高于底层。与环境因子相关性分析表明,水平方向上,影响南海北部表层海水细菌总数和细菌生产力的主要因; 素是温度、盐度、硝酸盐(NO_3-N)、硅酸盐(SiO_3-Si)、亚硝酸盐(NO_2-N)和磷酸盐(PO_4-P)(P<0.05);垂直方向上; ,影响南海北部可培养细菌总数的主要因素是NO_2-N(P<0.05),影响细菌生产力的主要影响因素是温度和盐度(P; <0.05)。可见,南海北部表层海水中细菌总数高于可培养细菌总数2; ~3个数量级,表明该海域表层海水存在大量不可培养细菌;细菌的生命活动在海水表层相较底层更为活跃。Distribution of abundance and production of bacteria and their; correlations with environmental factor were investigated, using plate; count method and flow cytometry, in the surface and vertical waters of; the northern south China sea in August 2014. The cultivable bacterial; abundance ranged from 3.70 * 10~2 CFU/mL to 1.42 * 10~3 CFU/ mL, the; total bacterial abundance ranged from 5.12 * 10~5 cells/mL to 1.61 *; 10~6 cells/mL and the bacterial productions varied from 0.03 mg/m~3/h to; 0.40 mg/m~3/h in horizontal distribution. In vertical distribution, the; cultivable bacterial abundance ranged from 1.08 * 10~3 CFU/mL to 9.00 *; 10~3 CFU/mL and the bacterial productions varied from 0.01 mg/m~3/h to; 0.08 mg/m~3/h, respectively. The correlation analysis results showed; that the environmental factors affecting the abundance of total bacteria; and bacterial productivity included temperature, salinity,; nitrate(NO_3-N),silicate (SiO_3-Si), nitrite (NO_2-N),and phosphate; (PO_4-P) (P<0.05). NO_2-N was the main influencing factor to cultivable; bacteria abundance (P < 0.05), while bacterial productivity was highly; correlated with temperature and salinity in vertical distribution of; northern south China sea (P < 0.05). The total bacterial abundance was 2; ~ 3 orders of magnitude higher than cultivable bacteria, suggesting that; there were many uncultured bacterium in surface water of northern south; China sea and bacterial activities in the surface maybe more active than; in the bottom.全球变化与海气交互作用; 国家重点研发计划全球变化及应对专项; 海洋公益性行业科研专

    Characteristics of nitrogen and phosphorus losses from swine production systems in Jiulong River watershed

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    由于对畜禽粪便的处置和管理不当,氮、磷养分随粪便大量流失,不仅带来日益突出的环境问题,还造成了资源的浪费。目前国际上多采用养分平衡方法研究和评价畜牧养殖场养分流失状况及其潜在的环境风险程度。选取福建省九龙江流域92家养猪场,采用养分平衡分析方法研究了该流域养猪场养分流失状况及主要影响因素。结果表明:大部分养猪场的氮磷养分输入量远远大于养分有效输出量,表明养分大量流失,养殖系统的环境风险程度极高;随着养猪场规模的增大,氮、磷的不平衡程度呈下降趋势;生态型养殖模式有利于促进资源综合利用,减少养分流失;加强对粪肥和饲料管理有利于促进畜禽养殖场的氮、磷养分平衡。Huge losses of nitrogen and phosphorus from the livestock production systems are known as the waste of resources and the sources of the environmental quality problems. Nutrient balance at farm level is an important tool to study the environmental problems associated with livestock production. A nutrient balance was constructed for 92 swine production systems of Jiulong River watershed, Fujian Province. The majority of the farms exhibited substantially greater nutrient inputs than nutrient managed outputs and it was in the status of an overaccumulation of nutrients; the nutrient imbalance decreased with farm scales; ecological production was a preferred mode to make better use of resources and decrease the losses of nutrients; management of feed and manure was helpful to balance the nutrients of livestock farms.福建省重大科技项目(2002H009)资

    童趣视频宣教联合母亲陪伴对学龄前全身麻醉患儿围手术期不良结局的影响

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    目的探讨童趣视频宣教联合母亲陪伴干预对学龄前全身麻醉患儿围手术期不良结局的影响,包括麻醉诱导配合度,围手术期焦虑、苏醒期疼痛和躁动情况。方法本研究选择2023年6月至12月期间在我院接受全身麻醉的300例学龄前期手术患儿作为研究对象,随机将患者分为对照组和干预组,每组各150例。对照组实施常规复苏,而干预组在常规复苏的基础上,术前一天访视,母亲与患儿共同观看手术麻醉童趣视频且接受宣教,入手术室等候和术后苏醒30 min时,母亲分别被引导陪伴患儿持续超过30 min。通过手术麻醉信息系统记录复苏情况并使用改良耶鲁围手术期焦虑量表(m-YPAS)、麻醉诱导期合作量表(ICC)、儿童疼痛行为量表(FLACC)及儿童躁动评估量表(PAED)评估和记录患儿麻醉诱导配合度,围手术期焦虑、疼痛和躁动情况。结果术前一天访视时,两组患儿一般资料差异无统计学意义(P>0.05)。围手术期焦虑方面,干预组的mYPAS评分显著低于对照组(入手术室等候时35.27±6.48比41.79±6.68,P<0.05;术后苏醒30 min时20.13±7.05比35.75±9.51,P<0.05)。麻醉诱导配合度方面,干预组ICC评分显著低于对照组(1.84±0.95比3.17±0.62,P<0.05),且诱导配合度良好的比例显著高于对照组(24.00%比12.67%,P<0.05)。苏醒时长无明显差异,但复苏室停留时长显著短于对照组[(0.90±0.29) h比(1.29±0.42) h,P<0.001]。围手术期躁动方面,干预组PAED评分显著低于对照组(入手术室等候时8.5比9.2,P<0.05;术后苏醒30 min时4.2比7.8,P<0.05)。疼痛评分方面,干预组FLACC评分也显著低于对照组(入手术室等候时5.3比6.7,P<0.05;术后苏醒30 min时2.1比4.9,P<0.05)。结论童趣视频宣教与母亲陪伴的联合干预策略有效降低学龄前期全身麻醉手术患儿的围手术期焦虑、疼痛、躁动,提高麻醉诱导依从性,建议在临床实践中推广应用此干预措施

    Synthesis and Applications of Carbon Dots

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    近年来,由于碳纳米材料具有高的催化活性以及好的稳定性等优点,其在科学、工程以及商业领域都得到了广泛的应用。其中新型“零维“碳纳米材料——碳量子点(CArbOn dOTS,CdS)具有荧光信号稳定、无光闪烁、激发波长和发射波长可调控等独特的光学性质,以及生物毒性小和生物相容性好等优势,逐渐成为碳纳米材料的研究热点,广泛应用于生物成像、生物细胞标记、传感器、光催化、太阳能电池以及发光元件等领域。本文主要综述了CdS的不同合成方法(包括自上而下法和自下而上法)及其应用。In recent years,nanomaterials have made an important impact on diverse science,engineering,and commercial sectors due to their high catalysis,lowcost,and good stability.Acting as a class of ‘zero-dimensional'carbon nanomaterials,carbon dots( CDs) possess unique optical properties of high photostability against photobleaching,tunable excitation and emission wavelength,as well as lowcytotoxicity and good biocompatibility.Therefore,CDs have become a hot subject of carbon nanomaterial in the past decade,not only for its unique properties but also for its applications in various fields such as bioimaging,biolabeling,sensors,photocatalysis,solar cells, light-emitting element and so on.This article reviews the different synthetic methodologies( including two classes: top-down and bottom-up) to achieve good performance of CDs.At the same time,the applications of CDs are also reviewed in the article.国家质检总局科技计划项目(No.2012QK053); 福建省质量技术监督局科技项目(No.3002A91429); 福建省高校产学合作科技重大项目(No.2012H6026); 福建省自然科学基金项目(No.2012D136); 福建省教育厅科技项目(No.JB14180)资助~

    大孔吸附树脂分离纯化龙胆药材中龙胆苦苷和马钱子苷酸的研究

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    目的:建立利用大孔吸附树脂对龙胆药材中龙胆苦苷和马钱子苷酸进行富集和分离纯化的方法。方法:采用加速溶剂萃取法对龙胆药材中两种有效成分进行高效提取,比较了D301,AB-8,D101,XDA-1四种大孔树脂对龙胆苦苷和马钱子苷酸的吸附性能,最终确定采用D301型大孔对脂对二者进行富集吸附,对其工艺参数进行优化,全程采用高效液相色谱进行目标化合物浓度检测。结果:化优后的工艺参数为:上样浓度:0.2 g/mL,最大上样量:0.25 g龙胆药材/g树脂,最佳静态吸附时间:8 h,采用8%和55%的乙醇溶液对龙胆苦苷和马钱子苷酸分别进行洗脱;龙胆苦苷和马钱子苷酸分别富集在8%和55%的乙醇洗脱液中,洗脱液浓缩后冷冻干燥,可得到纯度分别为74.3%和80.9%的粗产物,龙胆苦苷和马钱子苷酸的回收率分别为70.11%和67.82%。结论:此法效率较高,操作简便,即可用于实验室制备少量的难以购置的标准品,也可进行放大研究,用于工业生产。国家自然科学基金重点项目(20235020);; 青岛“2004将才计划”(04-3-JJ-11);; 共建生物医药研发测试中心(LS-05-KJZX-76)资
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