基于降噪自编码器特征学习的作者识别及其在《西游记》诗词上的应用

由于作者归属问题较为复杂,采用传统自然语言处理模型难以完成作者识别.为了深入挖掘作者归属问题,首先采用降噪自编码器深度模型提取文本结构特征,再采用支持向量机分类器完成作者识别.模型的优势在于能够考虑未知文本特征的噪声多样性和复杂性,且能够重构添加噪声的原始文本输入.将该方法应用于吴承恩、王廷陈、薛蕙等人的诗词作者识别,识别准确率最高为78.2%,验证了该方法的有效性,进一步将该方法应用于《西游记》诗词作者识别.国家自然科学基金(61673322,61573294

Study on the Refolding of Recombinant Human Granulocyte-Colony Stimulating Factor by Ion Exchange Chromatography

本文研究了以包含体形式表达的重组人粒细胞集落刺激因子（rhG-CSF）在常用的 脉一精氨酸辅助复性溶液体系中的复性过程，在稀释复性的基础上，着重考察了离子 交换色谱复性，并以反相色谱为主要分析手段探讨了rhG-CSF在两种复性方式中折 叠的不同特点，探讨了rhG-CSF在不同复性方式下复性效果不同的原因，分析了影 响离子交换色谱复性效果的主要因素并提出了改进的思路。首先考察并比较了rhG-CSF在无添加剂的缓冲液、加有L-精氨酸的缓冲液、以 及脉一精氨酸混合溶液中的稀释复性的特点。发现了用脉作为变性系统的rhG-CSF包 含体蛋白稀释复性的蛋白收率要明显高于用盐酸肌作变性剂的现象，并发现在服一精 氨酸混合溶液中稀释时，复性体系中的脉浓度对于折叠平衡状态的影响很大，必须低 于4mol／L刁一能使rhG-CSF复性。 然后研究了以DEAE SePharose Fast Flow为代表的阴离子交换柱上复性 rhG-CSF。除了使用常规的NaCl溶液作为洗脱剂外，尝试了将精氨酸直接用作离子 交换色谱复性的洗脱剂，显著地提高了色谱复性效率。通过比较三缓冲液系统（流动 相按高浓度变性剂一低盐复性缓冲液一高盐复性缓冲液的顺序转换）和双缓冲液系统（流动相按高浓度变性剂一高盐复性缓冲液的顺序转换）的两种洗脱方式对于复性效 果的影响，提出：1）在被吸附于离子交换介质上的状态下，rhG-CSF难以折叠复性， 复性在洗脱过程中，蛋白具有一定的空间自由度时才能发生，因此，通过降低蛋白质 分子数和色谱吸附位点数的比值来减小洗脱时蛋白在柱中的拥挤程度可能是提高复 性效率的一个重要途径；2）洗脱时流动相中足够低的腮浓度对于rhG-CSF复性是重 要的，双缓冲液系统洗脱方式复性的rhG-CSF的活性之所以比稀释复性和三缓冲液 系统洗脱方式复性的rhG-CSF都明显偏低，和洗脱时流动相脉浓度太高有关。此外，还尝试了在CM Sepharose Fast Flow阳离子交换柱上复性rhG-CSF，将合 适的pH梯度与脉梯度联合使用可以明显提高复性效果，但阳离子交换复性的pH难 以控制，容易生成无活性的中间体，总蛋白收率也比较低。用反相色谱作为主要分析手段对rhG-CSF在精氨酸溶液中，脉一精氨酸混合溶液 中的稀释复性，阴离子交换色谱柱上的穿过复性以及阴、阳离子交换色谱复性进行了 监测，比较了它们各自的特点，并由此对各种复性方法的复性效果差异进行了解释，发现并着重分析了阴离子交换色谱复性的rhG-CSF独特的折叠状态。实验中还发现，如果将阴离子交换色谱复性的rhG-CSF进一步稀释，则其RPC 图谱特征将向稀释复性的特征转化，而且其活性增高。这提示将离子交换色谱复性和 稀释复性结合起来，利用稀释手段弥补色谱复性的不足是有可能的

反相色谱法研究人粒细胞集落刺激因子的离子交换色谱复性和稀释复性

以反相色谱分析为主要手段,结合活性测定,研究了以包含体形式表达的重组人粒细胞集落刺激因子(rhG-CSF)的稀释复性和离子交换色谱复性. 建立了L-精氨酸离子交换复性蛋白质的方法,将变性、还原的rhG-CSF吸附到高浓度变性剂平衡的离子交换色谱柱上,用L-精氨酸作洗脱剂进行梯度洗脱并同时脱除变性剂,实现了rhG-CSF的复性. 与稀释复性相比,色谱复性的rhG-CSF处于一种中间状态,呈现快速而不同步的动力学特点,这与色谱复性的梯度洗脱及固定相的吸附有关. 同时发现了对复性峰进一步稀释并且温育则可以提高其活性的新现象

碳热还原法合成LaSiN∶Ce蓝色荧光粉及其发光性能研究

利用碳热还原法制备了LaSiN∶Ce蓝色荧光粉,重点研究了原料中掺C量和退火对样品纯度及发光性能的影响。通过X射线衍射仪和荧光光谱仪分别表征样品的晶体结构和发光性能。研究结果表明:1 600℃时能够合成主相为LaSiN∶Ce的荧光粉。在360nm紫外光激发下样品可获得波段范围在38000nm的单峰宽带发射谱,归结于Ce的5d-4f的能级跃迁。当n/n=4/1时样品发光强度达到最大,并且光谱出现先红移后蓝移的现象。经过退火的样品的发光强度与退火前相比提高了60%45%。将热处理后的n/n=4/1的样品与商用YAG混合涂覆在UV芯片上(λ=365nm)封装成WLED,证实了LaSiN∶Ce在白光LED领域潜在的应用价值。国家重点研发计划项目(2017YFB0403105)资助

Syntheses and Photoluminescence Properities of LaSi3N5 : Ce3+ Blue Phosphors by Carbothermal Reduction Method

利用碳热还原法制备了LaSi3 N5:Ce3+蓝色荧光粉,重点研究了原料中掺C量和退火对样品纯度及发光性能的影响.通过X射线衍射仪和荧光光谱仪分别表征样品的晶体结构和发光性能.研究结果表明:1600℃时能够合成主相为LaSi3 N5:Ce3+的荧光粉.在360 nm紫外光激发下样品可获得波段范围在380~600 nm的单峰宽带发射谱,归结于Ce3+的5d-4f的能级跃迁.当n C/n La=4/1时样品发光强度达到最大,并且光谱出现先红移后蓝移的现象.经过退火的样品的发光强度与退火前相比提高了60%~345%.将热处理后的n C/n La=4/1的样品与商用YAG混合涂覆在UV芯片上(λem=365nm)封装成WLED,证实了LaSi3 N5:Ce3+在白光LED领域潜在的应用价值.LaSi3N5 : Ce3+ blue phosphors were prepared by carbothermal reduction method. The influence of C content and heat dealing on purity and luminescence of samples were investigated. The phosphors were characterized by X-ray diffraction (XRD) and fluorescence spectrophotometer (PL). XRD patterns revealed that LaSi3N5 : Ce3+ could be combusted at 1 600 degrees C. There was a single-peak broadwide emission spectrum between 380 similar to 600 nm due to the electron transfer of Ce3+ from 5d-4f excited by 360 nm. The luminescence intensity reached the maximum value atn(C)/n(La) =4/1 followed by a continuous decline with a red shift and then a blue shift appeared in the spectrum. The luminescence intensity of samples improved 60%similar to 345% after heat-dealing. WLED were fabricated by applying a blend mixture of the sample and commercial YAG on a UV chip (lambda blend m), which indicated that LaSi3N5 : Ce3+ blue phosphor had a potential application value in WLED.国家重点研发计划项目(2017YFB0403105

Syntheses and Photoluminescence Properities of LaSi_3N_5 ∶Ce~(3+) Blue Phosphors by Carbothermal Reduction Method

利用碳热还原法制备了LaSi_3N_5∶Ce~(3+)蓝色荧光粉,重点研究了原料中掺C量和退火对样品纯度及发光性能的影响。通过X射线衍射仪和荧光; 光谱仪分别表征样品的晶体结构和发光性能。研究结果表明: 1; 600℃时能够合成主相为LaSi_3N_5∶Ce~(3+)的荧光粉。在360nm紫外光激发下样品可获得波段范围在380~; 600nm的单峰宽带发射谱,归结于Ce~(3+)的5d-4f的能级跃迁。当nC/n_(La)=4/1时样品发光强度达到最大,并且光谱出现先红移后; 蓝移的现象。经过退火的样品的发光强度与退火前相比提高了60%~345%。将热处理后的nC/n_(La)=4/1的样品与商用YAG混合涂覆在UV芯; 片上(lambda_(em)=365nm)封装成WLED,证实了 LaSi_3N_5∶Ce~(3+)在白光LED领域潜在的应用价值。LaSi_3N_5∶Ce~(3+)blue phosphors were prepared by carbothermal reduction; method.The influence of C content and heatdealing on purity and; luminescence of samples were investigated.The phosphors were; characterized by X-ray diffraction(XRD) and fluorescence; spectrophotometer(PL).XRD patterns revealed that LaSi_3N_5∶Ce~(3+)could; be combusted at 1 600℃.There was a single-peak broadwide emission; spectrum between 380~600nm due to the electron transfer of Ce~(3+)from; 5d-4 fexcited by 360nm.The luminescence intensity reached the maximum; value atnC/n_(La)=4/1 followed by a continuous decline with a red shift; and then a blue shift appeared in the spectrum.The luminescence; intensity of samples improved 60%~345%after heat-dealing. WLED were; fabricated by applying a blend mixture of the sample and commercial YAG; on a UV chip(lambdablend m),which indicated that LaSi_3N_5∶Ce~(3+)blue; phosphor had a potential application value in WLED.国家重点研发计划项

甘油介导的疏水色谱复性重组人α-干扰素

<正> 蛋白质的折叠复性是生物工程下游技术的瓶颈问题,传统的复性方法由于聚集沉淀而活性蛋白收率很低。采用色谱方法复性蛋白质具有独特的优点,近年来倍受蛋白质工作者的关注。凝胶过滤色谱、离子交换色谱和金属螯和色谱都曾被成功地用于复性某些蛋白质。本实验室采用发展了脲梯度以及脲-pH值双梯度的色谱复性方法,使复性收

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies