P-RC APMP PULPING OF THE TRIPLOID OF POPULUS TOMENTOSA

The technology parameters of P-RC APMP process of the triploid of populus tomentosa and the the comparison of P-RC APMP with one and two stage f pretreatment were investigated in this paper. The results showed that in the chemical pretreatment the s that affected the pulp qualities. The charge of NaOH,y in the first stage of chemical pretreatment,was related to pulp strength. The charge of H2O2 tant pulp.In addition, the ratio of NaOH to H2O2 and the on of chemicals in the first and second stage of impregnation also affected the pulp qualities. The and two-stage P-RC APMP pulp illustrated that the ulp had better brightness and breaking length, lower light scatting coefficient and opacity.     

CHARACTERISTICS OF BENTONITE AND ITS SYNERGISTIC RETENTION EFFECT WITH CPAM ON WHEAT STRAW PULP

INTRODUCTIONIn papermaking industry, microparticle retention aid systems have been widely accepted in past decade because of their simultaneous improvements on retention and drainage but with no sacrifice in formation compared with conventional polymer retention systems. Polyacrylamide/bentonite is one of the typical microparticle retention aid systems,in which highly anionic charged bentonite is used as the microparticle component. The flocculation mechanism of this microparticle retentio…     

掺铒光纤放大器特性研究

在放大器增益特性实验研究中,采用两个９８０ｎｍ的ＬＤ作为泵浦光源进行双向泵浦,研究了放大器的增益与光纤长度、泵浦功率以及信号光功率的关系,获得了３３ｄＢ的最大净增益。计算了放大器的噪声系数,得到具有良好的噪声特性的结果。     

电极表面涂敷对电荷注入的影响

在强电场的作用下，绝缘介质中的载流子除杂质离子外一般是徕自电极注入，文中采用电极表面涂敷改性ＳＰ硅漆，形成“金属电极－涂敷层－涂体介质”复合界面，有效地降低了电极注入强度，由地电极注入与其极板极性有着密切关系，还讨论了涂敷不同极性的电极极板对电荷注入的影响。     

COMPARISON OF APMP PULP CHARACTERISTICS OF JUVENILE TRIPLOID CHINESE WHITE POPLAR IN SALINE SOIL WITH THAT OF NORMAL 5-YEAR POPLAR

INDRODUCTIONAs we all known, the characteristics of Chinese papermaking and pulping industry are small scale, low-grade products and serious pollution in that the shortage of fiber supply. The effective method for developing Chinese papermaking is integrated forest-paper production by developing fast-growing plantation wood.Common characteristics for the pulps from various wood species of the Populus family are low long fiber yield, high bulk and relatively low strength values. On the ot…     

REFINING BEHAVIOR OF BAMBOO LONG FIBER FRACTION PULP

Refining of pulp significantly contributes to papermaking process by affecting the runnability of the stock and quality of end product. The greater the production rates of a paper, the greater are the effects of machine downtime through breaks. A correct approach towards refining treatment is very essential for energy savings and product with desired properties. Papermakers are being encouraged to use non-wood fibres for a variety of reasons - the environment, changing agricultural policy and long-term fibre supply. Compared with wood fibres,there is less knowledge on how to treat non-wood fibres for optimum performance. Laboratory studies aimed at understanding the behaviour of unbleached bamboo long fibre fraction pulp on refining in Escher Wyss Laborefiner under simulated process conditions included investigations of the important parameters like wet web tensile, wet web elongation, water retention value and paper strength properties. The paper describes the influence of two specific edge loads, 1000 and 1500 Ws/km on refining of pulp.Bamboo long fibre fraction pulp responds better to lower intensity refining to develop pulp strength.     

耐热木聚糖酶助漂针叶木硫酸盐浆的研究

探讨了嗜热真菌耐热木聚糖酶助漂针叶木硫酸盐浆的应用前景.着重研究了应用耐热木聚糖酶进行生物助漂的酶用量、酶处理的pH值以及漂白用氯量等影响因素.结果表明,在不影响纸浆的各项性能的情况下,经酶处理的纸浆白度相比对照增加1.06%~5.11%ISO.同时,酶处理纸浆漂白时可减少漂白用氯量.另外,在偏碱性条件下进行酶处理对纸浆漂白效果的影响较为显著.纸浆纤维的扫描电镜结果显示,酶未对纤维造成损伤,而是改善了纸浆纤维的可漂性.该耐热木聚糖酶非常适宜应用于酶助漂.     

干制加工对龙眼果肉多酚组成及抗氧化活性的影响

研究了龙眼果肉干制过程中肉干燥前后总酚的含量、存在形式及单体酚的组成和其抗氧化能力差异.结果表明,龙眼果肉经干燥后游离酚含量及其FRAP抗氧化活性和DPPH抗氧化活性均显著下降(P＜0.05);结合酚含量及其FRAP抗氧化值显著上升(P＜0.05),但其DPPH抗氧化值变化不明显(P＞0.05).经过干燥后,龙眼游离酚...     

燃煤添加剂的助燃性能研究

选取了 5种金属氧化物或盐 ,利用热重分析的方法 ,分析了它们对煤的发热量、着火温度等燃烧特性的影响 ,并据此制备了一种燃煤添加剂 .研究结果表明 ,该燃煤添加剂可有效降低煤的着火温度 ,增加煤燃烧的发热量 ,当添加剂加入量为0 .2 %时 ,可使发热量增加 1 3.0 % ,着火温度下降约 3～ 5℃ .     

聚合物的空间电荷效应与电击穿机理

本文采用电声脉冲法,实测了聚乙烯试样中空间电荷分布,在特制的试样上,显示了均匀电场中空间电荷在直流击穿和短路击穿中的极性效应.空间电荷效应、交直流叠加和升压速度的实验结果表明,均匀电场中聚乙烯的击穿规律与极不均匀电场中树枝化的特性是一致的,进一步证明了 Budenstein 的实验发现,即均匀电场中聚合物的击穿起始于界面的树枝化.最后,作者用高氏树枝化新理论,对击穿现象作出了满意的解释.     

苯甲酰苯胺衍生物分子内电荷转移与质子转移的取代基效应

1971年O'Connell等首次在EPA(ethyl ether:isopentane:ethanol=5:5:2,体积比)玻璃体(77 K)中观察到苯甲酰苯胺(BA)发射Stokes位移高达15 000 cm-1的"异常"长波长荧光(430 nm),其波长甚至长于磷光(410 nm)发射这一现象并未引起人们重视直到1987年,Kasha等首次在室温非极性溶剂甲基环己烷中观察到了BA的双重荧光发射,分别位于约320 nm处的极弱的荧光和470 nm处的强的"异常"荧光.     

气溶胶粒子形状对其辐射特性影响的研究

在处理大气的长、短波辐射时常常假定粒子为球形。本用扩展边界条件法及Ｍｏｎｔｅ－Ｃａｒｌｏ方法计算了随机取向的非球形气溶胶粒子的衰减、吸收截面、相函数、不对称因子、单次散射反照率等辐射参量，研究了形状因子及粒子表面粗糙度对这些量的影响。     

充电电压对铅蓄电池及其电极性能的影响

对铅蓄电池进行不同充电电压的充放循环试验,测量了循环寿命期间单电极电流与电位的变化关系,分析了电极的极化性能、充电特性及正极电位对板栅腐蚀及电池寿命的影响,并讨论了优化的充电方武。     

纳米凹凸棒土对碳纤维/BMI树脂复合材料的增强与增韧

采用预浸料模压工艺制备了纳米凹凸棒土／短碳纤维／ＢＭＩ树脂复合材料。实验并分析了纳米凹凸棒土对复合材料的增强与增韧作用,当其质量百分比为５％～６％时,弯曲强度和冲击强度分别提高了３０％和５７％。     

dentonin对牙髓干细胞增殖的实验研究

目的研究dentonin促进牙髓干细胞增殖,获得有关dentonin对牙髓干细胞增殖的实验证据。方法把构建好的含有真核细胞表达质粒pc DNA-dentonin,在脂质体Lipofect AMINE介导下,转染到体外培养的牙髓干细胞,再进行MTT检测细胞增殖。结果发现dentonin对牙髓干细胞生长有明显的增殖作用。结论牙髓干细胞生长速度较快,但是在两周后进入平台期,牙髓干细胞生长速度减慢。     

THE EFFECT OF DIFFERENT STABILIZERS ON ALKALINE H_2O_2 BLEACHING OF NS REED PULP

INTRODUCTIONHydrogen peroxide (H2O2) is a "green" bleaching agent which is widely used in the bleaching of various pulps. Since H2O2 is easy to decompose, stabilizer is necessary to inhabit the decomposing of H2O2 during the bleaching process. There are many kinds of stabilizer and Na2SiO3 is one of the common used stabilizers. However, the dissolution of Na2SiO3 is relative worse, which brings many troubles to the application. This study uses a new stabilizer for H2O2 bleaching and…     

THE EFFECT OF DIFFERENT STABILIZERS ON ALKALINE H2O2 BLEACHING OF NS REED PULP

This paper uses a new stabilizer of H2O2 bleaching and compares the stabilizing effect of the new stabilizer with that of Na2SiO3. The results show that the new stabilizer is better than the conventional Na2SiO3. The optimum conditions of the stable latter process bleaching of H2O2 as follow: NaOH 3%,MgSO4 0.05%, H2O2 3%, stabilizer 3%, temperature 80℃, concentration 12%, time 3h.     

底部空气柱装药爆破机理分析与试验研究

应用激波理论分析了底部空气柱装药爆破机理。通过实验室的爆破漏斗试验，研究了底部空气柱装药爆破效果，掌握了定量装药在固定装药深度情况下爆破漏斗体积与底部空气柱长度的变化规律，对工程实践有一定指导意义。     

THE COMPARISON OF STRENGTH PROPERTY BETWWEEN KRAFT PULP AND ALKALINE SULFITE-ANTHRAQUINONE PULP FOR THICKER CELL WALL FIBER MATERIALS

INTRODUCTIONMany studies on the strengths of AS-AQ pulp have been carried out. Generally speaking, except lower tear strength, other strength properties of AS-AQ pulp are similar to those of KP. Some even higher than KP[1,2]. Macleod[3] find that the difference in tear strength between the AS-AQ pulp and KP of aspen can be decreased about bleaching. McDonough et al[4] point out that at the same beating degree, the tear strength of AS-AQ pulp is lower than that of KP, but at the …