Natural Vulcanization Accelerators in Hevea Latex

1948 ◽  
Vol 21 (4) ◽  
pp. 853-859
Author(s):  
R. F. A. Altman

Abstract As numerous investigators have shown, some of the nonrubber components of Hevea latex have a decided accelerating action on the process of vulcanization. A survey of the literature on this subject points to the validity of certain general facts. 1. Among the nonrubber components of latex which have been investigated, certain nitrogenous bases appear to be most important for accelerating the rate of vulcanization. 2. These nitrogen bases apparently occur partly naturally in fresh latex, and partly as the result of putrefaction, heating, and other decomposition processes. 3. The nitrogen bases naturally present in fresh latex at later stages have been identified by Altman to be trigonelline, stachhydrine, betonicine, choline, methylamine, trimethylamine, and ammonia. These bases are markedly active in vulcanization, as will be seen in the section on experimental results. 4. The nitrogenous substances formed by the decomposition processes have only partly been identified, on the one hand as tetra- and pentamethylene diamine and some amino acids, on the other hand as alkaloids, proline, diamino acids, etc. 5. It has been generally accepted that these nitrogenous substances are derived from the proteins of the latex. 6. Decomposition appears to be connected with the formation of a considerable amount of acids. 7. The production of volatile nitrogen bases as a rule accompanies the decomposition processes. These volatile products have not been identified. 8. The active nitrogen bases, either already formed or derived from complex nitrogenous substances, seem to be soluble in water but only slightly soluble in acetone.

Algorithms ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 14
Author(s):  
Jianjian Ji ◽  
Gang Yang

Existing image completion methods are mostly based on missing regions that are small or located in the middle of the images. When regions to be completed are large or near the edge of the images, due to the lack of context information, the completion results tend to be blurred or distorted, and there will be a large blank area in the final results. In addition, the unstable training of the generative adversarial network is also prone to cause pseudo-color in the completion results. Aiming at the two above-mentioned problems, a method of image completion with large or edge-missing areas is proposed; also, the network structures have been improved. On the one hand, it overcomes the problem of lacking context information, which thereby ensures the reality of generated texture details; on the other hand, it suppresses the generation of pseudo-color, which guarantees the consistency of the whole image both in vision and content. The experimental results show that the proposed method achieves better completion results in completing large or edge-missing areas.


2020 ◽  
Vol 34 (10) ◽  
pp. 13955-13956
Author(s):  
Yiru Wang ◽  
Pengda Si ◽  
Zeyang Lei ◽  
Yujiu Yang

Neural generation models have shown great potential in conversation generation recently. However, these methods tend to generate uninformative or irrelevant responses. In this paper, we present a novel topic-enhanced controllable CVAE (TEC-CVAE) model to address this issue. On the one hand, the model learns the context-interactive topic knowledge through a novel multi-hop hybrid attention in the encoder. On the other hand, we design a topic-aware controllable decoder to constrain the expression of the stochastic latent variable in the CVAE to reduce irrelevant responses. Experimental results on two public datasets show that the two mechanisms synchronize to improve both relevance and diversity, and the proposed model outperforms other competitive methods.


2021 ◽  
Vol 887 ◽  
pp. 493-498
Author(s):  
Alexey D. Zhukov ◽  
I.I. Popov ◽  
Igor V. Bessonov ◽  
S.P. Chernukhin

The increase of thermo-physical properties of masonry made of ceramic burnt products is possible through the use of heat-efficient ceramics and, in particular, porous building tiles. The use of combustible additives or foaming technology is related to increased energy costs and difficulties in obtaining products with uniformly distributed porosity.The analysis of the state of the technology of ceramic materials made it possible to formulate a research hypothesis according to which the use of a porous non-combustible additive in the composition of ceramic masses, on the one hand, will make it possible to obtain materials with a lower density compared to traditional ceramic products, and, on the other hand, will allow the use of hard mixtures with reduced water content, and therefore significantly save the cost of drying products, while increasing the uniformity of the porous ceramic crock.The purpose of the research was to develop recipes for ceramic porous products and to develop modes of their burning. The use of crushed foam glass as a lightweight non-burning and exhausting additive, on the one hand, made it possible to use tough ceramic mixtures (with a water content not exceeding 18%), and, on the other hand, to use more rigid and shorter drying modes, which also reduced the energy and material consumption of the technology.The most energy-intensive burning process was optimized by the methods of mathematical planning and processing of experimental results. The average density of crushed foam glass (140–150 kg/m3), optimal for the burnt product, was established, and also, as a result of analytical optimization and interpretation of the experimental results, dependencies that allow choosing parameters and evaluating product properties depending on foam glass consumption and burning temperature were obtained.


Author(s):  
Stefan Krause ◽  
Markus Appel

Abstract. Two experiments examined the influence of stories on recipients’ self-perceptions. Extending prior theory and research, our focus was on assimilation effects (i.e., changes in self-perception in line with a protagonist’s traits) as well as on contrast effects (i.e., changes in self-perception in contrast to a protagonist’s traits). In Experiment 1 ( N = 113), implicit and explicit conscientiousness were assessed after participants read a story about either a diligent or a negligent student. Moderation analyses showed that highly transported participants and participants with lower counterarguing scores assimilate the depicted traits of a story protagonist, as indicated by explicit, self-reported conscientiousness ratings. Participants, who were more critical toward a story (i.e., higher counterarguing) and with a lower degree of transportation, showed contrast effects. In Experiment 2 ( N = 103), we manipulated transportation and counterarguing, but we could not identify an effect on participants’ self-ascribed level of conscientiousness. A mini meta-analysis across both experiments revealed significant positive overall associations between transportation and counterarguing on the one hand and story-consistent self-reported conscientiousness on the other hand.


2005 ◽  
Vol 44 (03) ◽  
pp. 107-117
Author(s):  
R. G. Meyer ◽  
W. Herr ◽  
A. Helisch ◽  
P. Bartenstein ◽  
I. Buchmann

SummaryThe prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term diseasefree survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT.This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.


2003 ◽  
pp. 15-26
Author(s):  
P. Wynarczyk
Keyword(s):  
The Core ◽  

Two aspects of Schumpeter' legacy are analyzed in the article. On the one hand, he can be viewed as the custodian of the neoclassical harvest supplementing to its stock of inherited knowledge. On the other hand, the innovative character of his works is emphasized that allows to consider him a proponent of hetherodoxy. It is stressed that Schumpeter's revolutionary challenge can lead to radical changes in modern economics.


2018 ◽  
Vol 4 (1) ◽  
pp. 67-84
Author(s):  
Wahyudin Noor

Abstract Pesantren are often associated with backwardness and traditionalism in everything: facilities, technology, learning methods, and even the curriculum. For now, it seems like the traditional term for pesantren is no longer relevant enough. The pace of movement in the era of renewal marked by the rapid development of technology has demanded pesantren to make adjustments. However, on the one hand, when viewed from the direction of change, the reform efforts pursued by pesantren are not to erase the old tradition, but merely to add something new so that the old tradition and conditions can be maintained while accepting the presence of a new one. On the other hand, the reform efforts undertaken by pesantren have implications for the fact that the typical values of the pesantren are fading away. Abstrak  Pesantren seringkali diasosiasikan dengan keterbelakangan dan tradisional dalam segala hal: fasilitas, teknologi, metode pembelajaran, dan bahkan kurikulumnya. Untuk saat ini, sepertinya istilah tradisional untuk pesantren, sudah tidak lagi cukup relevan. Laju gerak pembaharuan zaman yang ditandai dengan pesatnya perkembangan teknologi telah menuntut pesantren untuk melakukan penyesuaian diri. Kendatipun demikian, di satu sisi, jika dilihat dari arah perubahan, upaya pembaharuan yang ditempuh pesantren tidaklah untuk menghapus tradisi yang lama, tetapi sekadar menambah dengan sesuatu yang baru sehingga tradisi maupun kondisi yang lama bisa dipertahankan sambil menerima kehadiran yang baru. Di sisi yang lain, upaya pembaharuan yang dilakukan pesantren ternyata berimplikasi pada kenyataan akan semakin pudarnya nilai-nilai khas yang dimiliki oleh pesantren.


2018 ◽  
Vol 1 (1) ◽  
pp. 37-52
Author(s):  
Karimatul Khasanah
Keyword(s):  

BASYARNAS’s verdict in resolving dispute can be negotiated or cancelled by submitting nullification to the Religious Court if the parties or one of them felt dissatisfied with the BASYARNAS verdicts. This case is important to be reviewed academically because of its paradox and ambiguity. On the one hand the decision is final and binding, but on the other hand it could be cancelled through the Religious Court. If the BASYARNAS verdicts really want to be final and binding, the nullification of the verdicts should be abolished. It can be replaced by an amendment of the verdict submitted to BASYARNAS and handed back to the arbitrator (arbitrator panel) who handles the dispute. Apart being fast and confidential, the arbitrator (judge) is more aware of the case, the reasons, evidences and witnesses of the dispute.


2020 ◽  
Vol 65 (4) ◽  
pp. 401-422
Author(s):  
Estelle Variot
Keyword(s):  
The One ◽  

"Etymological, Lexical and Semantic Correspondences in the Process of Feminization of Professional Names, Trades and Activities in French and Romanian Societies. The feminization of thought represented by language and of its varieties in the Roman World has allowed to highlight some convergences that come from a common linguistic heritage, often from Greek and Latin and some hesitation about adapting society to its realities. The feminization of some words which comes from an ancient process illustrates on the one hand the potential of the language and on the other hand some constraints sometimes linked to the society itself, which creates transitional periods, between matching grammatical correction and the evolution of linguistic uses over time. The possibilities of lexical enrichment (internal creation or loan) show the means available in French and Romanian and some convergences in the area of derivation, of lexical units and their etymologies. The grammatical perspective and word constructing methods make it possible to give keys for the feminization of names of trades or professions. Likewise, recording entries in the lexicon, their evolution, their assimilation or sometimes their forgetfulness, for the benefit of new constructions highlight the existence of objective and subjective criteria which teach us a lot about society as a whole. Keywords: feminization of professions, internal and external enrichment, suffixal match, use of words, grammar, lexicon, French and Romanian."


Imbizo ◽  
2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Naomi Epongse Nkealah ◽  
Olutoba Gboyega Oluwasuji

Ideas of nationalisms as masculine projects dominate literary texts by African male writers. The texts mirror the ways in which gender differentiation sanctions nationalist discourses and in turn how nationalist discourses reinforce gender hierarchies. This article draws on theoretical insights from the work of Anne McClintock and Elleke Boehmer to analyse two plays: Zintgraff and the Battle of Mankon by Bole Butake and Gilbert Doho and Hard Choice by Sunnie Ododo. The article argues that women are represented in these two plays as having an ambiguous relationship to nationalism. On the one hand, women are seen actively changing the face of politics in their societies, but on the other hand, the means by which they do so reduces them to stereotypes of their gender.


Sign in / Sign up

Export Citation Format

Share Document