Improving characteristics of melamine–urea–formaldehyde resin by addition of blocked polyurethane prepolymer

Author

• Jun JiangEmail author
• Xiaoning Lu

Original

First Online: 

18 November 2016

DOI: 10.1007/s00107-016-1132-0

Cite this article as: 

Jiang, J. & Lu, X. Eur. J. Wood Prod. (2016). doi:10.1007/s00107-016-1132-0

Abstract

In this paper, the effect of blocked polyurethane prepolymer (BPUP) with four R values (the ratio of –NCO to –OH) and different blending proportions on the characteristics of melamine–urea–formaldehyde (MUF) resin were first investigated. The properties of the modified adhesive systems were examined by dynamic wettability and shear strength. The results indicated that the bonding performance and the wettability of high R value blending modification were superior to that of low R value case. In addition, the optimal bonding performance came from the MUF resin modified by 15% BPUP (R = 5) addition. Besides, the K value on wood substrates with different moisture contents (MC) was calculated by wetting model to interpret the wetting kinetics. The polymer blending adhesive has a potential capacity for making wood-based panels from high-moisture raw materials.

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Notions of justice in payments for ecosystem services: Insights from China's Sloping Land Conversion Program in Yunnan Province

Published Date
February 2015, Vol.43:207–216, doi:10.1016/j.landusepol.2014.11.011

Author 

Jun He ^a,b,c,1,,

Thomas Sikor ^b,1

aCollege of Economics and Management, Yunnan Agricultural University, Kunming 650201, China

bSchool of International Development, University of East Anglia, Norwich NR4 7TJ, UK

cWorld Agroforestry Centre, ICRAF East and Central Asia Program, Heilongtan, Kunming 650204, China

Received 29 March 2013. Revised 5 November 2014. Accepted 10 November 2014. Available online 1 December 2014.

Highlights

• China's Sloping Land Conversion Program (SLCP) is the world's largest payments for ecosystem services (PES) scheme.
• •
  State policy on the SLCP contains provisions for distributive and procedural justice.
• •
  Villagers, local officials and state policy share the concern about distributive justice.
• •
  The shared distributive concern contributes to reforestation and rising incomes.
• •
  Research needs to consider notions of justice for a fuller understanding of PES.

Abstract 

China's Sloping Land Conversion Program (SLCP) pays millions of farmers to convert cropland in upper watersheds to tree plantations. It is considered one of the world's largest payments for ecosystem services (PES) scheme for its reliance on financial incentives. This paper examines the outcomes of the SLCP by way of a case study from the Yangliu watershed in Yunnan province. It focuses on the notions of justice embedded in state policy and held by villagers and local state officials in order to understand the observed outcomes in terms of people's participation in the implementation of the SLCP, land use changes and livelihood effects. Villagers, local state officials, and state policy share a primary concern about distributive justice despite significant differences in their specific notions. The shared concern underlies the villagers’ positive reactions to the SLCP, which among other factors, have led to the intended expansion of tree plantations and a livelihood transition in Yangliu since 2003. The insights from Yangliu suggest the need to consider justice for a fuller understanding of the dynamics and outcomes of the SLCP and other PES schemes worldwide as the notions of justice applied by the involved actors may influence land use and livelihood dynamics in addition to the other factors considered in research this far.

Keywords

Justice

Payments for ecosystem services

Land-use change

Livelihoods

Policy implementation

China

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Fig. 1.

 Table 1

Table 1.

• ⁎ 
  Corresponding author at: College of Economics and Management, Yunnan Agricultural University, Kunming 650201, China. Tel.: +86 871 5223014; fax: +86 871 5223377.

For further details log on website :
http://www.sciencedirect.com/science/article/pii/S1389934116301289

Empirical linkages between devolved tenure systems and forest conditions: Selected case studies and country experiences

Published Date
December 2016, Vol.73:286–293, doi:10.1016/j.forpol.2016.05.018

Author 

• Miaoying Shi ^a
 
• Runsheng Yin ^b,,
 
• Leo Zulu ^c
 
• Jiaguo Qi ^d
 
• Mark Freudenberger ^e
 
• Matthew Sommerville ^e

• aDepartment of Forestry, Michigan State University, East Lansing, MI 48824, USA
• bCollege of Economics and Management, Northwest A&F University, Yangling 712100, China
• cDepartment of Geography, Michigan State University, East Lansing, MI 48824, USA
• dCenter for Global Change and Earth Observations, Michigan State University, East Lansing, MI 48824, USA
• eTetra Tech., 159 Bank Street, Suite 300, P.O. Box 1397, Burlington, VT 05402, USA

Received 12 March 2016. Accepted 21 May 2016. Available online 3 June 2016.

Highlights

• Selected case studies and meta-analyses of cases are first presented.
• •
  Experiences of forest tenure devolution in several countries are also described.
• •
  These elements are also essential to understanding the impact of devolved tenure.

Abstract

In addition to those more rigorous empirical analyses that have been summarized in the previous paper, a large number of case studies have tackled the linkages between devolved tenure systems and forest conditions. Some of the selected case studies and meta-analyses of these and other cases are described, so are the experiences of forest tenure devolution in several countries. We argue that complementary to those empirical analyses reviewed earlier, these two elements are also essential to anyone who is interested in a clear understanding of the specific contents, contexts of forest tenure devolution in different parts of the world and the possible causal linkages between devolved forest rights and improved forest condition.

Keywords

Forest devolution

Tenure reform

Community-based management

Forest condition

Impact evaluation

.

• ☆
  This article belongs to the special section: Forest devolution, forest condition, and poverty alleviation published in the journal Forest Policy and Economics 73, 2016.

• ⁎ 
  Correspondence author.

For further details log on website :
http://www.sciencedirect.com/science/article/pii/S1389934116301289

Empirical linkages between devolved tenure systems and forest conditions: Primary evidence

Published Date
December 2016, Vol.73:277–285, doi:10.1016/j.forpol.2016.06.033

Author 

• Runsheng Yin ^a,b,,
 
• Leo Zulu ^c
 
• Jiaguo Qi ^d
 
• Mark Freudenberger ^e
 
• Matthew Sommerville ^e

• aCollege of Economics and Management, Northwest A&F University, Yangling712100, China
• bDepartment of Forestry, Michigan State University, East Lansing, MI 48824, USA
• cDepartment of Geography, Michigan State University, East Lansing, MI 48824, USA
• dCenter for Global Change and Earth Observations, Michigan State University, East Lansing, MI 48824, USA
• eTetra Tech., 159 Bank Street, Suite 300, P.O. Box 1397, Burlington, VT 05402, USA

Received 12 March 2016. Revised 17 June 2016. Accepted 29 June 2016. Available online 21 July 2016.

Highlights

• Empirical research has unfolded along two distinct but complementary lines of inquiry.
• •
  One is local-level examinations of coupled forest conditions and institutional variables.
• •
  The other is regional-level studies of forest conditions against an array of variables.
• •
  Forest tenure reform and institutional change can lead to improved forest condition.
• •
  It is too soon to draw a strong and general conclusion on the direct causal linkages.

Abstract 

Empirical research on the relationship between devolved tenure and forest condition has unfolded along two distinct but complementary lines of inquiry. They include local-level examinations of closely coupled forest conditions and such institutional variables as rulemaking, enforcement, and monitoring; and regional-level analysis of resource conditions against an array of institutional and other variables, including different tenure systems or scenarios of before vs. after devolution or with vs. without. Large advances have made in defining the relevant variables and testing the causality. While some studies suggest that forest tenure reform and institutional change can lead to improved forest condition, it remains too soon to draw a strong and general conclusion on the direct causal linkage between devolved forest rights and improved forest condition. Knowledge gaps exist in terms of the quantity and quality of the evidence.

Keywords

Forest devolution

Tenure reform

Community-based management

Forest condition

Impact evaluation

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.

.

• ☆
  This article belongs to the special section: Forest devolution, forest condition, and poverty alleviation published in the journal Forest Policy and Economics 73, 2016.

• ⁎ 
  Corresponding author.

For further details log on website :
http://www.sciencedirect.com/science/article/pii/S1389934116301289