Automated Recognition Model of Geomechanical Information Based on Operational Data of Tunneling Boring Machines

Author(s):  
Haiqing Yang ◽  
Kanglei Song ◽  
Jiayuan Zhou
2020 ◽  
Vol 1575 ◽  
pp. 012043
Author(s):  
Dongdan Guo ◽  
Hao Sun ◽  
Tao Zhu ◽  
Chang Cai

TAPPI Journal ◽  
2012 ◽  
Vol 11 (7) ◽  
pp. 29-35 ◽  
Author(s):  
PETER W. HART ◽  
DALE E. NUTTER

During the last several years, the increasing cost and decreasing availability of mixed southern hardwoods have resulted in financial and production difficulties for southern U.S. mills that use a significant percentage of hardwood kraft pulp. Traditionally, in the United States, hardwoods are not plantation grown because of the growth time required to produce a quality tree suitable for pulping. One potential method of mitigating the cost and supply issues associated with the use of native hardwoods is to grow eucalyptus in plantations for the sole purpose of producing hardwood pulp. However, most of the eucalyptus species used in pulping elsewhere in the world are not capable of surviving in the southern U.S. climate. This study examines the potential of seven different cold-tolerant eucalyptus species to be used as replacements for, or supplements to, mixed southern hardwoods. The laboratory pulping and bleaching aspects of these seven species are discussed, along with pertinent mill operational data. Selected mill trial data also are reviewed.


1989 ◽  
Author(s):  
Charles L. Frame ◽  
Brian R. McEnany ◽  
Kurt A. Kladivko

1992 ◽  
Vol 27 (1) ◽  
pp. 185-202
Author(s):  
C.R. Erland Jansson

Abstract The UVOX process was developed to reduce the high concentrations of trihalomethanes, a potentially hazardous disinfection by-product found in a surface water supply for a community in northeastern Saskatchewan. Pilot plant tests were conducted at a throughput of 1.25 l/s utilizing UV to produce hydroxyl radicals from photolysis of H2O2 with air cooled UV units. These tests continued through 1985 andl986 to provide operational data for all seasons of the year. Test results indicated that the UVOX process was effective in reducing trihalomethane formation potential to very low levels. Recent concerns have also centred on the biocidal effectivenesss of disinfectants, particularly when applied to inactivation of resistant species of microogranisms, such as the cysts of Giardia lamblia. The UVOX process in a single pass configuration slightly enhanced the ability of UV to inactivate Giardia cysts.


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