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AN的相关文献在1958年到2023年内共计39138426篇,主要集中在无线电电子学、电信技术、数学、化学工业 等领域,其中期刊论文230篇、专利文献39138196篇;相关期刊186种,包括大学英语、中华内分泌代谢杂志、江苏医药等; AN的相关文献由50000位作者贡献,包括不公告发明人、王伟、张伟等。

AN—发文量

期刊论文>

论文:230 占比:0.00%

专利文献>

论文:39138196 占比:100.00%

总计:39138426篇

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AN

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  • 王伟
  • 张伟
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  • 李伟
  • 张磊
  • 刘伟
  • 王勇
  • 张涛
  • 李强
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    • 高小慧; 宋小兰; 王毅
    • 摘要: 为了减小AN的粒径,采用超低温喷射冻干法制备了纳米AN;采用扫描电镜(SEM)、光学显微镜(OM)、X射线衍射(XRD)、红外光谱(IR)和X光电子能谱(XPS)对样品进行了表征;采用差示扫描量热法(DSC)和热重-质谱(TG-MS)分析了其热分解性能;测试了纳米AN的机械感度和热感度,并与原料AN进行了对比.结果表明,制备出的纳米AN微观形貌呈类球形,粒径小于100nm;其分子结构、表面元素和晶相与原料AN一致;纳米AN的热分解活化能为92.11kJ/mol,较原料AN仅下降了 5.43kJ/mol,说明纳米化后其热稳定性基本不变;纳米AN热分解的产物为NH3、H2O和 N2O,与原料AN基本一致;纳米AN对机械作用非常钝感,10kg落球下特性落高(H50)大于110cm,摩擦感度爆炸百分比(P)为16%;但纳米AN热感度低于原料AN,其5s爆发点(T5s)为277°C,而原料AN的T5s 为266°C.
    • 孙惜媛; 解志斌; 宋科宁; 田雨波; 张贞凯; 毛云龙
    • 摘要: 通信系统的保密性在信息化作战体系中尤为重要.在存在窃听的多输入多输出(Multiple-Input Multi-ple-Output,MIMO)干扰对齐(Interference Alignment,IA)网络中,传统利用接收或发送端发送人工噪声(Artificial Noise,AN)实现物理层保密通信的方法,会增加收发端的能耗与实施复杂度.为此,提出一种基于MIMO协作IA网络的保密通信算法,推导出了算法可行性条件、合法用户传输速率和保密速率、窃听端窃听速率,并给出了相应的基于最小干扰泄露准则的分布式迭代IA实施方法,有效降低系统复杂度.仿真结果表明,所提算法在保证合法用户传输速率的同时抑制窃听速率,有效提高系统安全性能.
    • 谷际岐; 佟竺殷; 魏逸衡; 刘晓艺; 冯伟轩; 朱轩; 张少良
    • 摘要: 为了探明冻融过程对东北典型黑土耕层氮(N)生物有效性的影响,试验利用室内模拟方法,探究了不同冻结温度、土壤容重、含水量、冻融循环次数影响下耕层土壤剖面速效氮(AN)的时空分布规律。结果表明,经冻融循环后,土壤AN含量随土层深度增加呈现波动性下降;冻结温度越低,AN随土层深度增加下降的波动性越大,AN峰值、AN土柱平均值越低;冻结温度-15°C时整个土柱AN平均值比-10°C降低9.3%~44.6%;容重增高,AN含量降低,AN/TN值升高,土壤容重1.1 g/cm^(3)时整个土柱AN平均值比容重1.0 g/cm^(3)降低13.0%~18.6%,容重1.1 g/cm^(3)整个土柱AN/TN平均值比容重1.0 g/cm^(3)显著提升0.6~4.7倍;随着含水量的提高,低容重(1.0 g/cm^(3))表层(0—8 cm)AN越高,底层(20—30 cm)AN越低,而高容重(1.1 g/cm^(3))土柱表层(4—8 cm)AN越高,表层(0—4 cm)AN、底层(20—30 cm)AN越低;在各个变量中,pH大小与AN累积趋势呈负相关关系,含水量、TDS、电导率、冻结温度均与AN含量成正相关,是否冻融循环对AN垂直分布影响最大,其次是恒温及冻融循环次数(p<0.05)。研究结果可为黑土区冻融过程土壤N素管理、提升土壤肥力、减少N损失等问题提供理论依据和技术支撑。
    • 王毅; 宋小兰; 李凤生
    • 摘要: 以5-氨基四氮唑(5-ATZ)为前驱体合成了5,5′-偶氮四唑钾(PZT).将不同质量比的PZT和硝酸铵(AN)同时溶解在水中,然后将水蒸发,得到了几种"AN+PZT"复合物.用IR和XRD对PZT和"AN+PZT"复合物进行了相应表征.结果表明,IR图谱证明了所制备PZT的分子结构,并且说明PZT可能为一种水合物;XRD图谱表明,"AN+PZT"是一种多晶复合物;DSC图谱表明,PZT的存在完全抑制了AN在环境温度下的晶体相变,即原料AN在57.1°C下的相变吸热完全消失;所有"AN+PZT"复合物的热分解峰温与原料AN相比明显降低;原料AN热分解的最终产物为N2O、HNO3和H2O.与原料AN相比,"0.8AN+0.2PZT"的热分解未生成HNO3,但有NH3作为中间产物生成.推测在AN解离为NH3和HNO3后,HNO3先与PZT发生了反应,而NH3则剩余下来并在更高的温度下被HNO3氧化.由于AN热分解的控制步骤是其解离产物中HNO3的分解,因此PZT的引入在反应机理上促进了AN的热分解.
    • 鲁晶晶
    • 摘要: 目的 研究颅内动脉瘤(AN)介入栓塞术围术期精准护理的应用价值.方法 筛选出本院于2018年10月~2019年11月接收的94例AN患者为研究对象,将其随机划分为对照组和实验组,各47例.其中,对照组给予介入栓塞术围术期常规护理,实验组给予介入栓塞术围术期精准护理,对比两组的并发症发生率、护理前后的生活自理能力评分等指标.结果 实验组并发症发生率(10.64%)低于对照组(38.30%),差异存在统计学价值(P0.05);干预后,实验组的生活自理能力评分优于对照组,差异存在统计学价值(P<0.05).结论 对AN患者实施介入栓塞术治疗,并于围术期实施精准护理,能够大大地降低并发症发生率,增强患者的生活自理能力,是一个值得关注的治疗方案.
    • Suhad K. R. Al-Magsoosi; Albert K. Chong
    • 摘要: Recently, health problems related to weight gain and obesity have increased in all age groups, especially adults. Overweight and obese adults are associated with psychological, metabolic and musculoskeletal problems. The aim of this study was to examine foot-loading characteristics during gait of normal-weight;overweight and obese adults aged 25 - 46 years. Methods: This paper outlined tests that were performed on 30 feet of 15 participants. The subjects were gathered in three groups according to their body mass index values, each containing five study participants: five healthy weights (age 35.4 ± 6.3 yrs, BMI 21.9 ± 1.3 kg?/m2) matched to five overweight (age 39.2 ± 6.1 yrs, BMI 27.5 ± 1.34 kg?/m2);and five obese adults (age 36.5 ± 7.8? yrs, BMI 34.5 ± 10.3 kg?/m2. The measurements were compared between these groups and the correlation of body mass index with the foot plantar pressure parameters was assessed. Results: The foot pressure measure in the obese group was greater under the metatarsal heads and the heel of the foot compared to the healthy weight group. Moreover, there were rises in pressure beneath the H, MF, second metatarsal and third metatarsal regions of the foot. It may be considered that in obese individuals, this variation resulted from greater weakness in the ligaments of the foot. As results, the obese group may suffer from discomfort in their feet. The choice of the footwear may depend on the gait and the resulting pain. In addition, they may be less likely to take part in walking or other activities. Therefore, further studies related to these issues, would be advisable. Conclusion: especially, the feet of obese individuals vary from those healthy and overweight adults, because obese subjects’ feet are wider. In the obese was established the greatest foot pressure measure in-creases beneath the heel of the foot and the metatarsal heads.
    • 蒋同山
    • 摘要: 数列实际上是一种特殊的函数,因而数列题也经常以函数的面目出现.一类比较常见的综合题是数列的通项an与前n项和Sn之间的函数关系,其主要模型为an=f(Sn)或an+1=f(Sn)等.本文拟从一道模型题及三道变式题探究其解题要点和主要思路.
    • Silviu Guiasu
    • 摘要: If Goldbach’s conjecture is true, then for each prime number p there is at least one pair of primes symmetric with respect to p and whose sum is 2p. In the multiplicative number theory, covering the positive integers with primes, during the prime factorization, may be viewed as being the outcome of a parallel system which functions properly if and only if Euler’s formula of the product of the reciprocals of the primes is true. An exact formula for the number of primes less than or equal to an arbitrary bound is given. This formula may be implemented using Wolfram’s computer package Mathematica.
    • Sharofiddin Allaberdiev; Shokhrukh Yakhyoev; Rakhmatilla Fatkhullayev; Jia Chen
    • 摘要: Due to requirements and necessities in digital image research, image matching is considered as a key, essential and complicating point especially for machine learning. According to its convenience and facility, the most applied algorithm for image feature point extraction and matching is Speeded-Up Robust Feature (SURF). The enhancement for scale invariant feature transform (SIFT) algorithm promotes the effectiveness of the algorithm as well as facilitates the possibility, while the application of the algorithm is being applied in a present time computer vision system. In this research work, the aim of SURF algorithm is to extract image features, and we have incorporated RANSAC algorithm to filter matching points. The images were juxtaposed and asserted experiments utilizing pertinent image improvement methods. The idea based on merging improvement technology through SURF algorithm is put forward to get better quality of feature points matching the efficiency and appropriate image improvement methods are adopted for different feature images which are compared and verified by experiments. Some results have been explained there which are the effects of lighting on the underexposed and overexposed images.
    • C. Michael B. Henderson; Paul R. Lythgoe; Karen J. Theis
    • 摘要: Operating an Agilent 7700X ICP-MS spectrometer under robust plasma conditions (1550 W) with a He-filled octopole collision cell and analysing solutions (?1 total dissolved solids) still suffered analyte peak suppression due to matrix effects. International reference rocks BCR-1, BHVO-1, AGV-1, G-2 and BCR-2 all showed count rate reductions for 36 elements (mass range 7Li to 238U) averaging ~10% but with no dependence on isotope mass. Use of an internal standard (103Rh) and/or using a ten-fold dilution of sample solutions reduced these effects but problems with reduced count rates combined with larger errors for some elements introduced other problems. The best approach was to normalise the count rates for each element in the other samples against those for BCR-1 as an external standard;thus the count suppression due to the matrix effect is corrected for each individual element. This approach provides standardization “traceability” in line with the ERM ISO/IEC requirement. Experiments are also reported on quantifying the proportions of Ba and selected REE oxide/hydroxide components versus parent isotopes (XO/X and XOH/X). This information is essential for correcting peak interferences on higher mass number REE for the rock samples, and equations are developed to use measured CeO/Ce and CeOH/Ce ratios to predict such values for any other member of the REE suite. Concentrations obtained show excellent agreement with recommended values for the international reference materials especially for the REE. Robust data are also provided for two other standard rocks: nepheline syenite STM-1 and quartz syenite CAAS-1;the latter shows exceptional enrichments of Zr, REE, Th, and U.
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